AAT (was Re: Evaluation of evidence (Can Twitch address the argument w/out changing the subject?))
Sherilyn
myke_r...@yahoo.com wrote:
...
> There is little
> point to attempting to engage in debate with a
> pedantic demagogue who does not even respond to
> the debating points that you put forward.
>
> This is precisely the problem I had with "Sherilyn"
...
> and it is the classic manner of
> argumentation adopted by bigots, i.e. people who are
> intollerantly convinced of their own opinion.
...
For a more balanced perspective on Mike Reynolds' above claim,
check out the Aquatic Ape threads on sci.anthropology.paleo for
April through July of last year. Mike made three major claims:
1) The Aquatic Ape Theory, that is, the theory that a number of
human characteristics are a result of a partial adaptation to
aquatic existence is "the current dominate theory of hominid
evolution, which led the Leaky's to their successful find of
pre-Lucy remains" and was first put forward by "the Royal
Academy of Science". [Actually, it's only one of several
contending hypotheses, was first proposed by the marine
biologist A.C. Hardy in 1960 ("Was man more aquatic in the past?"
_New Scientist_ 7 1960, pp. 642-5), and played no part in
the finds of any of the various Leakeys.]
http://www.dejanews.com/getdoc.xp?AN=238246252
Also check out long-time AAT proponent Elaine Morgan's response
to the above posting, at:
http://www.dejanews.com/getdoc.xp?AN=238712553
Elaine Morgan is a science writer who has championed
the AAT for nearly three decades, and has written
many books on the subject that have been well received,
given the controversial nature of the hypothesis, by
professionals in the field. Her latest books on the
subject are "The Scars of Evolution: What our bodies
tell us about human origins," ISBN: 019509431X, and
"The Descent of the Child: Human Evolution from a New
Perspective," ISBN: 0195098951.
2) "The aquatic ape theory is incontrovertible."
http://www.dejanews.com/getdoc.xp?AN=247582617
[Actually, there's some evidence for, and some evidence
against, the AAT, but the marked lack of human
fossils for the relevant period is well known. It's
certainly far to early to say that the story of human
origins is known in any detail.]
3) According to the Aquatic Ape Theory, "the development of
hominids is almost assure after the evolution of a semian
like genus."
http://www.dejanews.com/getdoc.xp?AN=238112174
[Michael's reasoning for this claim was never made clear,
but even the most enthusiastic proponents of the AAT
have never gone so far as to make the above proposal.]
For the bulk of his contributions on the AAT threads last year, Michael
seemed to be laboring under a misapprehension to the effect that I was
opposing the AAT as a possible explanation of human evolution (which I
certainly wasn't, as can be seen in the posting that I reference under
item (1) above), rather than taking issue with Michael's incorrect
statements which I have summarised above. In the end I killfiled him
because he was becoming increasingly abusive and intolerant. It seems
to me that Michael is fond of projecting his own intolerance onto other
people.
--
Sherilyn
-----== Posted via Deja News, The Leader in Internet Discussion ==-----
http://www.dejanews.com/rg_mkgrp.xp Create Your Own Free Member Forum
Marc Verhaegen
Sherilyn heeft geschreven in bericht <6tbtug$fjq$1...@nnrp1.dejanews.com>...
> Academy of Science". [Actually, it's only one of several
> contending hypotheses, was first proposed by the marine
> biologist A.C. Hardy in 1960 ("Was man more aquatic in the past?"
> _New Scientist_ 7 1960, pp. 642-5), and played no part in
> the finds of any of the various Leakeys.]
Hardy was probably not the first, but - independently - Max Westenhöfer in
Germany & possibly G.L.Sera in Italy (both medical doctors).
> 2) "The aquatic ape theory is incontrovertible."
> http://www.dejanews.com/getdoc.xp?AN=247582617
> [Actually, there's some evidence for, and some evidence
> against, the AAT, but the marked lack of human
> fossils for the relevant period is well known. It's
> certainly far to early to say that the story of human
> origins is known in any detail.]
>
"marked lack of human fossils"? & what is the "relevant period"?
If you mean "lack of hominid fossils", I'll be glad to repeat my list. This
list does not prove the aquatic theory, but it certainly does not exclude
it.
? Lukeino KNM-LU 335 “pre-australopithecine”: ‘The red beds seems to contain
marginal lacustrine deposits as indicated by the presence of algal mats and
lacustrine bivalves (including complete specimens with valves in the closed
position)’ (Pickford, 1975).
? Tabarin KNM-TH 13150 “pre-australopithecine”: ‘The fauna includes aquatic
animals such as molluscs, fish, turtles, crocodiles, and hippotami, along
with others that might be found in the vicinity of a lake of river’ (Ward &
Hill, 1987).
? Ardipithecus ramidus: ‘Sedimentological, botanical and faunal evidence
suggests a wooded habitat for the Aramis hominids […] Aquatic elements
(turtle, fish, crocodile) are rare. Large mammals (hippopotamus,
proboscideans, rhinos, equids, giraffids, bovines) are rare. Primates are
very abundant’ (WoldeGabriel et al., 1994); ‘[…] interpreted to have been a
closed woodland. At Aramis, aquatic species and large mammals are rare, and
colobines make up over 30% of all vertebrate specimens collected’ (Leakey et
al., 1995).
? Kanapoi KNM-KP 29281 Australopithecus anamensis: Fish, aquatic reptiles,
kudus and monkeys are prevalent. ‘A wide gallery forest would have almost
certainly been present on the large river that brought in the sediments’
(Leakey et al., 1995).
? Chad KT 12 A. cf. afarensis: ‘The non-hominid fauna contains aquatic taxa
(such as Siluridae, Trionyx, cf. Tomistoma), taxa adapted to wooded habitats
(such as Loxodonta, Kobus, Kolpochoerus) and to more open areas (such as
Ceratotherium, Hipparion) […] compatible with a lakeside environment’
(Brunet et al., 1995).
? Garusi-Laetoli L.H. A. anamensis or afarensis: Teeth and mandible
fragments, the hardest skeletal parts which are frequently left over by
carnivores (Morden, 1988), come from wind-blown and air-fall tuffs, but
always near watercourses at the time (Leakey et al., 1976). Cercopithecine
and colobine monkeys are present (Protsch, 1981; Leakey et al., 1976).
? Hadar, Afar Locality: ‘Generally, the sediments represent lacustrine, lake
margin, and associated fluvial deposits related to an extensive lake that
periodically filled the entire basin’ (Johanson et al., 1982)
? Hadar AL.333 A. afarensis: ‘The bones were found in swale-like features
[…] it is very likely that they died and partially rotted at or very near
this site […] this group of hominids was buried in streamside gallery
woodland’ (Radosevich et al., 1992).
? Hadar AL.288 gracile A. afarensis: Lucy lay in a small, slow moving
stream. ‘Fossil preservation at this locality is excellent, remains of
delicate items such as crocodile and turtle eggs and crab claws being found’
(Johanson & Taieb, 1976).
? Makapan A. africanus: ‘[…] very different conditions from those prevailing
today. Higher rainfall, fertile, alkaline soils and moderate relief
supported significant patches of sub-tropical forest and thick bush, rather
than savannah. Taphonomic considerations […] suggest that sub-tropical
forest was the hominins’ preferred habitat rather than grassland or
bushveld, and the adaptations of these animals was therefore fitted to a
forest habitat’ (Rayner et al., 1993; see also Reed, 1993; and Wood, 1993).
? Taung australopithecine: ‘the clayey matrix from which the Taung cranium
was extracted, and the frequent occurrence of calcite veins and void
fillings within it (Butzer 1974, 1980) do suggest a more humid environment
during its accumulation’ (Partridge, 1985).
? Sterkfontein A. africanus & Swartkrans A. robustus: Many South African
australopithecines are discovered in riverside caves, presumably often
filled with the remainders of the consumption process of large felids
(Brain, 1981).
? Kromdraai: A. robustus was found near grassveld and streamside or marsh
vegetation, in the vicinity of quail, pipits, starlings, swallows, and
parrots, lovebirds and similar psittacine birds (T. N. Pocock in Brain,
1981).
? Turkana KNM-ER 17000 & 16005: A. aethiopicus was discovered near the
boundary between overbank deposits of large perennial river and alluvial fan
deposits, amid water- and reedbucks (Walker et al., 1986).
? Lake Turkana: ‘The lake margins were generally swampy, with extensive
areas of mudflats […] Australopithecus boisei was more abundant in fluvial
environments, whereas Homo habilis was rare in such environments […]
Australopithecus fossils are more common than Homo both in channel and
floodplain deposits. The gracile hominids […] seem to be more restricted
ecologically to the lake margin than are the robust forms’ (Conroy, 1990).
? Ileret A. boisei: ‘the fossil sample reflects climatic and ecological
environmental conditions differing significantly from those of the present
day. At Ilerat, 1.5 Myr ago, climatic conditions must have been cooler and
more humid than today, and more favourable to extensive forests […] The
prominence of montane forest is particularly striking […] dominated by
Gramineae and Chenopodiaceae appropriate to the margins of a slightly saline
or alkaline lake’ (Bonnefille, 1976).
? Konso A. boisei: ‘The highly fossiliferous sands at the mid-section of
KGA10 are interpreted to be the middle to distal portions of an alluvial
fan, deposited adjacent to, and extending into, a lake. Fossils and
artefacts deriving from horizons of sands and silts are not abraded and show
evidence of minimal transport. A large mammalian assemblage has been
collected from the deposits, showing a striking dominance of Alcelaphini […]
to indicate the presence of extensive dry grasslands at KGA10’ (Suwa et al.,
1997).
? Chesowanja A. boisei: ‘The fossiliferous sediments were deposited in a
lagoon […] Abundant root casts […] suggest that the embayment was flanked by
reeds and the presence of calcareous algae indicates that the lagoon was
warm and shallow. Bellamya and catfish are animals tolerant of relatively
stagnant water, and such situation would also be suitable for turtles and
crocodiles’ (Carney et al., 1971).
? Olduvai middle Bed I: A. boisei O.H.5 as well as habilis O.H.7 and O.H.62
were found in the most densely vegetated, wettest condition, with the
highest lake levels (Walter et al., 1991), near ostracods, freshwater
snails, fish, and aquatic birds (Conroy, 1990); ‘[…] the middle Bed-I faunas
indicate a very rich closed woodland environment, richer than any part of
the present-day savanna biome in Africa […] (Fernández-Jalvo et al., 1998).
Fossilized leaves and pollen are rare in the sediments of Beds I and II, but
swamp vegetation is indicated by abundant vertical roots channels and casts
possibly made by some kind of reed. Fossil rhizomes of papyrus also suggest
the presence of marshland and/or shallow water’ (Conroy, 1990). ‘[…]
Cyperaceae fruits were common in H. habilis habitat (Bonnefille, 1984).
Ancient Egyptians ate Cyperus papyrus root which was also present at Olduvai
in swamp-margins and river banks’ (Puech, 1992).
? Olduvai O.H.24 habilis: ‘Crocodile remains predominate among the faunal
material from this site and more than 2,000 teeth were found. Tortoise
plates, shells of Urocyclid slugs, fish vertebrae and scales, bird bones and
pieces of ostrich eggshell were also relatively common (Leakey et al.,
1971).
? Malawi UR 501 early Homo: ‘The Plio-Pleistocene Chiwondo Beds of Northern
Malawi have yielded molluscs and fragmented remains of fish, turtles,
crocodiles and large mammals […] Microvertebrates and carnivores are
virtually unrepresented in the assemblage […] The general ecological setting
of the Malawi Rift during the Late Pliocene was a mosaic environment
including open and closed, dry and wet habitats, and which harbored a small
and ecologically unstable paleolake Malawi’ (Schrenk et al., 1995).
? Chemeron KNM-BC1 early Homo: ‘The Fish Beds […] seem to be almost entirely
lacustrine and fluviatile; fish remains are abundant […] Molluscs also lived
in the lake, and locally their remains accumulate to form shelly limestones’
(Martyn & Tobias, 1967).
? Turkana Boy KNM-WT 15000 H. erectus: ‘Mammalian fossils are rare at this
locality, the most abundant vertebrate fossils being parts of small and
large fish. The depositional environment was evidently an alluvial plain of
low relief […] Typical lacustrine forms (for example, ostracods, molluscs)
could invade the area […] The only other fauna found so far in the
fossiliferous bed are many opercula of the swamp snail Pila, a few bones of
the catfish Synodontis and two fragments of indeterminate large mammal bone
[…]’ (Brown et al., 1985).
? Mojokerto H. erectus: ‘The basal part of the Putjangan Beds is composed of
volcanic breccias containing marine and freshwater molluscs. The rest of the
Putjangan Beds is composed of black clays of lacustrine origin’ (Ninkovich &
Burckle, 1987).
? Peking H. erectus: ‘A big river and possibly a lake were located to the
east and contained various water species; along the shorelines grew reeds
and plants, which were home for buffalo, deer, otters, beavers and other
animals’ (Poirier, 1978); ‘[…] accumulation in quiet water. The cave at this
time was probably the locus of ponded water and was probably more open to
the athmophere’ (Weiner et al., 1998).
? Hopefield, Rabat & Terra Amata: H. erectus fossils came from sandstone
made up from dune sand resting upon a former sea beach (DeLumley 1990). In
Terra Amata, ‘there are also indications that the inhabitants ate oysters,
mussels and limpets – shells of which are present. The presence of fish
bones and fish vertebrae indicate that the population also fished’ (Poirier,
1987).
Marc
Sherilyn
"Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
>
> Sherilyn heeft geschreven in bericht <6tbtug$fjq$1...@nnrp1.dejanews.com>...
[someone claimed that:]
>
> > 2) "The aquatic ape theory is incontrovertible."
> > http://www.dejanews.com/getdoc.xp?AN=247582617
> > [Actually, there's some evidence for, and some evidence
> > against, the AAT, but the marked lack of human
> > fossils for the relevant period is well known. It's
> > certainly far to early to say that the story of human
> > origins is known in any detail.]
> >
> "marked lack of human fossils"? & what is the "relevant period"?
Sorry, hominids. The relevant period is about 15 to 4 MYA.
>
> If you mean "lack of hominid fossils", I'll be glad to repeat my list. This
> list does not prove the aquatic theory, but it certainly does not exclude
> it.
...
I agree. The excellent conditions for fossilization in riparian conditions
leads to fossil finds predominantly on shorelines, river beds, lakes, and
so on--this is where rapid sedimentation occurs. The question of whether
hominids of the period were undergoing adaptation to aquatic existence is
still open.
Marc Verhaegen
Sherilyn heeft geschreven in bericht <6tesje$ikp$1...@nnrp1.dejanews.com>...
>In article <6teglh$pb5$1...@xenon.inbe.net>,
> "Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
>>
>[someone claimed that:]
>>
>> > 2) "The aquatic ape theory is incontrovertible."
>> > http://www.dejanews.com/getdoc.xp?AN=247582617
>> > [Actually, there's some evidence for, and some evidence
>> > against, the AAT, but the marked lack of human
>> > fossils for the relevant period is well known. It's
>> > certainly far to early to say that the story of human
>> > origins is known in any detail.]
>> >
>> "marked lack of human fossils"? & what is the "relevant period"?
>
>>
lived in Eurasia (Dryo-, Ourano-, Ankarapith...).
For the early African hominids up to 4 mya, I repeat a (very small) part of
my list:
- Lukeino KNM-LU 335 “pre-australopithecine” ca.6 mya: ‘The red beds seems
to contain marginal lacustrine deposits as indicated by the presence of
algal mats and lacustrine bivalves (including complete specimens with valves
in the closed position)’ (Pickford, 1975).
aquatic animals such as molluscs, fish, turtles, crocodiles, and hippotami,
along with others that might be found in the vicinity of a lake of river’
(Ward & Hill, 1987).
suggests a wooded habitat for the Aramis hominids […] Aquatic elements
(turtle, fish, crocodile) are rare. Large mammals (hippopotamus,
proboscideans, rhinos, equids, giraffids, bovines) are rare. Primates are
very abundant’ (WoldeGabriel et al., 1994); ‘[…] interpreted to have been a
closed woodland. At Aramis, aquatic species and large mammals are rare, and
colobines make up over 30% of all vertebrate specimens collected’ (Leakey et
al., 1995).
reptiles, kudus and monkeys are prevalent. ‘A wide gallery forest would have
almost certainly been present on the large river that brought in the
sediments’ (Leakey et al., 1995).
Conclusions from this (meagre) information:
- earliest African hominids (Lukeino & Tabarin): association with bivalves.
This is not seen in later australopiths, but it is seen 3-4 my later in
erectus & ergaster.
- Ardipith: forest (gallery or tropical forest?).
- early & gracile australopiths (from anamensis to africanus): gallery
forests.
>> If you mean "lack of hominid fossils", I'll be glad to repeat my list.
This list does not prove the aquatic theory, but it certainly does not
exclude it.
>...
>I agree. The excellent conditions for fossilization in riparian conditions
leads to fossil finds predominantly on shorelines,
shorelines??
(no australopith remains on shorelines, vs. several erectus & neandertals
remains on shorelines)
> river beds, lakes, and so on--this is where rapid sedimentation occurs.
> The question of whether hominids of the period were undergoing adaptation
to aquatic existence is
>still open.
IMO 4-2 mya some hominids (=australopiths) were adapting to a more
terrestrial life again, some hominds (=Homo) were still evolving "further"
to a more diving life.
You know my view on this period:
1) IMO the australopiths of that period were (re)adapting to a more
terrestrial life (from bipedal wading in mangrove & gallery forests >
knuckle-walking in tropical forests, with a dietary shift from fruits (incl.
nuts) + shellfish in the LCA with humans (cf. Lukeino & Tabarin?), to fruits
+ aquatic herbac.vegetation (AHV) in the graciles, to fruits + cane & sedges
in the robusts, and to fruits + terrestrial herbac.vegetation (THV) in
chimps & gorillas.
2) Homo adapted to an even more aquatic life (more diving & shellfish
consumption at first, cf. beginning of stone tools, then - with the acquired
technology - inland in several parallel lineages).
Sherilyn
"Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
>
> Sherilyn heeft geschreven in bericht <6tesje$ikp$1...@nnrp1.dejanews.com>...
...
> >
> >Sorry, hominids. The relevant period is about 15 to 4 MYA.
> >>
> Isn't that too far back? Before 8 mya our closest relatives seem to have
> lived in Eurasia (Dryo-, Ourano-, Ankarapith...).
Okay, no problem.
> For the early African hominids up to 4 mya, I repeat a (very small) part of
> my list:
...
[list snipped for brevity]
> Conclusions from this (meagre) information:
[conclusions based on meagre information snipped]
Thank you. We appear to have an adequate basis for agreement there, that
the question of whether hominids of the period were undergoing adaptation
to aquatic existence is therefore still open. I do not see the point of
disputing your conclusions because there is inadequate evidence either to
support or refute them.
Gerrit Hanenburg
>? Garusi-Laetoli L.H. A. anamensis or afarensis: Teeth and mandible
>fragments, the hardest skeletal parts which are frequently left over by
>carnivores (Morden, 1988), come from wind-blown and air-fall tuffs, but
>always near watercourses at the time (Leakey et al., 1976). Cercopithecine
>and colobine monkeys are present (Protsch, 1981; Leakey et al., 1976).
Actually, of the whole list of sites, this is one of the most
interesting. Laetoli is one of the rare occasions where hominin
fossils are associated with non-waterlaid sediments.
A fossil that is associated with a waterlaid sediment can, in
principle, come from anywhere and need not have had any relation to
that particular depositional environment during life.
However, that is unlikely to have been the case with the aeolian
deposits at Laetoli. In general wind is not strong enough to transport
remains of vertebrates over long distances.
The implication is that Laetoli gives important information about
where these hominins where actually making a living.
Notable is the absence of aquatic taxa in the Upper Laetolil Beds,
(i.e. no fish, freshwater turtles, crocodiles, hippos) (Harris 1985).
According to Andrews (1989: 180): "the community structure of the
fauna is most similar to that of the woodland end of the Serengeti
spectrum today".
Harris, J.M. (1985) Age and Paleoecology of the Upper Laetolil Beds,
Laetoli, Tanzania. In Ancestors: The Hard Evidence. Delson, E. (ed).,
p.76-81.
Andrews, P.J. (1989) Palaeoecology of Laetoli. Journal of Human
Evolution 18: 173-181.
Gerrit
Marc Verhaegen
Gerrit Hanenburg heeft geschreven in bericht
<35fbddb1...@news.kijfhoek.nl.net>...
>Marc Verhaegen <Marc.Ve...@village.uunet.be> wrote:
>
>>? Garusi-Laetoli L.H. A. anamensis or afarensis: Teeth and mandible
>>fragments, the hardest skeletal parts which are frequently left over by
>>carnivores (Morden, 1988), come from wind-blown and air-fall tuffs, but
>>always near watercourses at the time (Leakey et al., 1976). Cercopithecine
>>and colobine monkeys are present (Protsch, 1981; Leakey et al., 1976).
>
>interesting. Laetoli is one of the rare occasions where hominin
>fossils are associated with non-waterlaid sediments.
part of Laetoli is air-fall
...
>According to Andrews (1989: 180): "the community structure of the
>fauna is most similar to that of the woodland end of the Serengeti
>spectrum today".
>
OK (colobines = forests)
Marc
Elaine Morgan
<Sher...@sidaway.demon.co.uk> writes>....
>part
> to the above posting, at:
> http://www.dejanews.com/getdoc.xp?AN=238712553
> Elaine Morgan is a science writer who has championed
> the AAT for nearly three decades, and has written
> many books on the subject that have been well received,
> given the controversial nature of the hypothesis, by
> professionals in the field. Her latest books on the
> subject are "The Scars of Evolution: What our bodies
> tell us about human origins," ISBN: 019509431X, and
> "The Descent of the Child: Human Evolution from a New
> Perspective," ISBN: 0195098951.
The last and best is "The Aquatic Ape Hypothesis", ISBN: 0285633775
Elaine
>
>
--
Gerrit Hanenburg
>>Actually, of the whole list of sites, this is one of the most
>>interesting. Laetoli is one of the rare occasions where hominin
>>fossils are associated with non-waterlaid sediments.
>part of Laetoli is air-fall
That is rather an understatement.
Almost the entire section of the Laetolil Upper Beds consists of
airfall and windreworked tuffs. Waterlaid deposits are rare (Harris
1985).
Gerrit
Marc Verhaegen
Gerrit Hanenburg heeft geschreven in bericht
>>part of Laetoli is air-fall
>
>That is rather an understatement.
>Almost the entire section of the Laetolil Upper Beds consists of
>airfall and windreworked tuffs. Waterlaid deposits are rare (Harris 1985).
>
Yes, when I wrote somewhere that Garusi-Laetoli was aeolian, some other
hair-splitter told me that part of it was not.
Marc
myke_r...@yahoo.com
nature of the argument that asserts that fossil remains
can not be associated with the location where they were
found. In specific instances certainly, but as a
general rule? It seems to me that if fossil remains
are consistently found near what was a shore at the
time of the creature's life, that this could no longer
be subject to an objection of anomalous fossil drifting?
-------------------------------------------------
I'd like to see an objective rebuttal of what I think
is the most compelling argument for AAT, which is the
morphology of pelvic bones in formerly terrestrial
aquatic and semi-aquatic marine animals. (I should
say formerly non-aquatic animals, but the statement
"formerly non-aquatic aquatic and semi-aquatic marine
animals" is ambiguous and difficult to parse.)
This assertion is based on comparing the orientation of
legs to torso. All large terrestrial limbed vertebrates
(besides humans) have between a 45 degree and 90 degree
angular separation between the orientation of the legs
and torso, and the lower limbs are oriented along a
vertical plane (in the belly down positioning of the body).
By contrast, many formerly non-aquatic marine animals
have legs that are oriented in the same direction as the
torso, or they had an ancestor with such an aligned
orientation before loosing their lower appendages. The
fossil remains of the intermediate evolutionary stage of
whales were discovered not too long ago, and they had legs
that were oriented in the same direction as the torso, swept
back behind the body, just like pinnipeds.
Other aquatic animals have limbs directed straight out
to the sides, but this is still similar to the straight
leg-torso aligned marine animals, and distinct from the
vertical limb orientation of most terrestrial animals, in
that the limbs are oriented along a horizontal plane rather
than a vertical plane the way ALL terrestrial *mammals*
are.
In semi-aquatic marine animals of this category, this
results in extremely cumbersome terrestrial locomotion,
where the animal has to crawl on it's belly because it
can't get it's legs underneath itself in the 90-45 degree
orientation of non-marine vertebrates. Penguins (and
potentially humans) are the only exception to this prone
posture in terrestrial locomotion for this class of
animals. (Sea otters are also an exception, but this is
due to cat like arching of the back to it's limits.)
Some animals have their femur and humerus aligned along
a horizontal plane, but the limbs are not straight, they
are bent precipitously at the elbow and knee joints,
entirely unlike the majority of marine animals who have
fully horizontal limbs that are straight and unbent. This
category of animals with a horizontally aligned femur
and humerus, but precipitously bent knees and elbows
consists mainly of small reptiles and amphibians. *No*
mammals are in this category. The only large animals
I can think of that fit this category are alligators
and crocodiles.
In summation, only marine adaptation is known to cause
an animal's limbs to evolve from being aligned along
a vertical plane relative to the torso, to being
aligned along a horizontal plane. Two types of
horizontal plane orientations exist, straight back,
and laterally out to the sides. Only the straight
back variety could potentially evolve into a fully
upright biped. (Note that no bipedal bird or dinosaur
has a fully upright posture. They conform to the
terrestrial orientation of a 45 to 90 degree angular
separation between legs and torso, entirely unlike
marine animals with limbs aligned along a horizontal
plane.)
Here is a list of animals who have their legs oriented
in the same direction as their torso, or who had an
ancestor with such: all Cetacea, all Sirenea, all
Pinnipedea, sea tortoises, pleisiosaurs, sea otters,
penguins and humans.
With the exception of humans, all other animals with
legs that are oriented in the same direction as their
torso, or who had an ancestor with such an aligned
orientation, are all aquatic or semi-aquatic marine
animals, with humans being supposed as the singular
exception by the anti-AAT argument.
Similarly, humans are the only supposedly non-marine
animals with subcutaneous fat. With the exception of
humans, there are no non-marine animals with subcutaneos
fat or straight leg-torso alignment. Aquatic adaptation
provides the only positively known means for producing
selective pressures that induce the formation of
subcutaneos fat and a straight leg-torso alignment.
The alternative argument is that straight leg-torso
orientation in hominids evolved from pressures that
give gibbons a different pelvic structure. But gibbons
do not have anything even remotely approaching a
straight leg-torso alignment, nor has this ever been
shown to occur in *ANY* non-marine animal. So in effect,
the anti-AAT argument poses pure supposition without
evidential support as being entirely superior to the
only positively known mechanism for the development of
subcutaneos fat and straight leg-torso alignment.
==================================================
No more anthropology; the following refers to a previous
thread on another newsgroup which just happened to have
spawned this thread.
As to the original subject of the thread where I
compared Sherilyn's arguments to Twitch's, Sherilyn
exemplified my point by failing to reference my
principle argument, just as she did throughout our
"debate"; if you can call interaction where the other
person does not ever respond to your principle argument
a debate. I admitted making false statements, but instead
of addressing my argument, she merely continued to repeat
my erroneous statements, which were entirely superfluous
to my principle argument. Or, she made reference to an
alternate theory about gibbon pelvic morphology, stating
that this had to be correct, without ever actually directly
rebutting my own argument. No matter how much I tried, I
was never able to get Sherilyn to directly address the
full scope of the above argument. She would take some
piece out of context, simply assert that it is not true,
and dismiss the rest of the argument in toto without
ever coherently addressing it.
One distinction however, I did make many mistakes along
the way in the presentation of my argument, and I modified
my argument accordingly as I was shown these mistakes.
Sherilyn claimed I was constantly changing my argument,
which is not entirely untrue, though it was an essentially
false characterization of what was in fact a continuous
refinement of an argument whose core principle remained
unchanged, i.e. vertical vs. horizontal limb orientation.
With my arguments with Twitch however, I have not changed
or refined my argument in any way since Twitch has never
addressed any salient criticism to my actual argument. I've
used slightly different wording in an attempt to get my
point across since Twitch was so completely unable to
comprehend the gist of my argument in the form I had
presented it. My point has always been about evaluation
criterion, without the slightest variation. So in this
regard, this criticism is far more egregiously manifested
in Twitch than in Sherilyn.
Sherilyn
myke_r...@yahoo.com wrote:
...
>
> As to the original subject of the thread where I
> compared Sherilyn's arguments to Twitch's, Sherilyn
> exemplified my point by failing to reference my
> principle argument, just as she did throughout our
Nonsense. I summarised Michael's three main points, which
are:
1) The AAT is the main theory of human origins, was first put
forward by "The Royal Academy of Science" (by which I take Michael
to mean The Royal Society) and influenced the Leakeys.
2) The AAT is incontrovertible
3) The AAT shows that the simian-to-hominid evolution
was almost inevitable.
All three claims are nonsense, of course, but I have summarised
them accurately, as can be confirmed by reference to Michael's
own words:
http://www.dejanews.com/getdoc.xp?AN=238112174
http://www.dejanews.com/getdoc.xp?AN=247582617
That Michael is uncomfortable with his own claims and continually
misrepresents my objection to them as if I were attempting to refute
a particular theory of human origins, well, that's his problem.
--
Sherilyn
myke_r...@yahoo.com
> myke_r...@yahoo.com wrote:
> > As to the original subject of the thread where I
> > compared Sherilyn's arguments to Twitch's, Sherilyn
> > exemplified my point by failing to reference my
> > principle argument, just as she did throughout our
>
> Nonsense. I summarised Michael's three main points, which
> are:
Sherilyn serves to prove my point. I stated my principle
supporting argument in great detail, but she makes no
reference to it now, as she never did then, no matter
how many times I attempted to get her to address the
subject in a salient manner. Instead she refers to
statements that are in no way, shape or form, supporting
arguments for a hypothesis.
> 2) The AAT is incontrovertible
This is not a supporting argument, this is an opinion.
> 3) The AAT shows that the simian-to-hominid evolution
> was almost inevitable.
This is not a supporting argument. It is a conjecture
based on assuming that the hypothesis is correct. If a
conjecture assumes a hypothesis to be correct at the
outset, how can it possibly be a supporting point for
the hypothesis? The conjecture is only true if the
hypothesis is proven correct, so it can not possibly
assist in proving the hypothesis.
> 1) The AAT is the main theory of human origins, was first put
> forward by "The Royal Academy of Science" (by which I take Michael
> to mean The Royal Society) and influenced the Leakeys.
I repeatedly recanted the statement about the Leakeys, but
Sherilyn hasn't let up about it to this day. But someone's
opinion is not a supporting argument for a theory anyway.
Also, while I stated that AAT was the "dominant theory",
I also stated that in a recent poll of the Royal Society
(not quite so recent now), 25% supported the theory and
75% did not. So clearly the context of the word dominant
was not as Sherilyn has attempted to twist it into. My
notion of what constitutes a dominant theory is not a
function of popularity contests. Dominant theories,
i.e. theories most supported by evidence, are often
rejected by the overwhelming majority of scientists before
it is eventually adopted.
And once again, this is not a supporting argument, this is
an expression of my opinion about the hypothesis (with the
exception of the Leakey statement which I apparently can
not recant enough for Sherilyn's satisfaction).
> All three claims are nonsense, of course, but I have summarised
> them accurately.
She has accurately reproduced two superfluous statements,
and inaccurately referenced a third superfluous statement,
while completely ignoring anything that could even remotely
be considered a supporting point for the argument. This is
precisely the comparison I was making between you and
Twitch. It is like trying to argue with a TV set.
> That Michael is uncomfortable with his own claims and continually
> misrepresents my objection to them as if I were attempting to refute
> a particular theory of human origins, well, that's his problem.
Talk about misrepresentation. Such hypocrisy! I don't
care what your opinion is, as long as you saliently
address the argument. Instead you completely ignore the
supporting arguments, time and time again, in favor of
the kind of ridiculous rebuttal to statements that are
utterly superfluous to the argument as you do above. And
even at that, you repeatedly twist these superfluous
statements out of context and perpetually refer to a
statement that I have repeatedly recanted.
As to my supposedly being uncomfortable with my own
statements, this is her odd why of acknowledging my
objection that these statements are not supporting
points, and so rebuttals to them are irrelevant.
Getting her to address ACTUAL supporting points is
a superhuman feat that I doubt anyone is capable of.
And in reference to the title of the thread, this is
no less true of "twitch". Quite a pair: Twitch and
the transvestite. Sounds like the title of a B rated
comedy.
Sherilyn
myke_r...@yahoo.com wrote:
> Sherilyn <Sher...@sidaway.demon.co.uk> wrote:
> > myke_r...@yahoo.com wrote:
> > > compared Sherilyn's arguments to Twitch's, Sherilyn
> > > exemplified my point by failing to reference my
> > > principle argument, just as she did throughout our
> >
> > Nonsense. I summarised Michael's three main points, which
> > are:
>
> Sherilyn serves to prove my point. I stated my principle
> supporting argument in great detail, but she makes no
> reference to it now, as she never did then, no matter
> how many times I attempted to get her to address the
> subject in a salient manner.
How odd. I was sure I had twice cited a URL for a posting
containing Michael's arguments for the supposed
"incontrovertibility" of the AAT in detail. In case Michael
missed it the first two times, here it is again:
http://www.dejanews.com/getdoc.xp?AN=247582617
> Instead she refers to
> statements that are in no way, shape or form, supporting
> arguments for a hypothesis.
On the contrary, Michael's hypothesis that intelligent aliens
would very likely be humanoid was supported by the three
false assertions that I have listed. If all three assertions
were true, then his hypothesis would have been well supported:
a strong inference drawn from an incontrovertible theory of
human origins that had solid physical evidence to back it up.
It's not my fault that all three planks of Michael's claim turned
out to be figments of his imagination.
>
> > 2) The AAT is incontrovertible
>
> This is not a supporting argument, this is an opinion.
Michael has somehow managed to lose the URL I cited in which
Michael tried to support this opinion, which was advanced in
support of his hypothesis about humanoid aliens. I quoted
it a third time in the opening paragraph of this posting.
> > 3) The AAT shows that the simian-to-hominid evolution
> > was almost inevitable.
>
> This is not a supporting argument. It is a conjecture
> based on assuming that the hypothesis is correct. If a
> conjecture assumes a hypothesis to be correct at the
> outset, how can it possibly be a supporting point for
> the hypothesis? The conjecture is only true if the
> hypothesis is proven correct, so it can not possibly
> assist in proving the hypothesis.
Michael claimed that the AAT was incontrovertible, and attempted
to support this claim. If it were, Michael clearly reasoned, then
simian-to-humanoid evolution was almost inevitable. And that is
good reasoning. This kind of reasoning (using a well supported
theory to advance an argument) is perfectly respectable and little
science could be done without it. So Michael is wrong to claim
that his conjecture could not prove his hypothesis. All he had to
do was demonstrate that the AAT was, as he claimed, "incontrovertible"
(or even well supported) _and_ (which would apparently be much harder,
at least Michael has never made the attempt) demonstrate that the
conjecture follows from the AAT.
>
> > 1) The AAT is the main theory of human origins, was first put
> > forward by "The Royal Academy of Science" (by which I take Michael
> > to mean The Royal Society) and influenced the Leakeys.
>
> I repeatedly recanted the statement about the Leakeys, but
> Sherilyn hasn't let up about it to this day.
I have seen no such recantation; the nearest to this is, on June 21st,
1997:
"I've read nothing from Leakey one way or the other, but I find
it highly improbable that Leakey did not know he was searching
in precisely the area predicted by AAT. I still strongly suspect
that this is a political ploy in order to get out of the line of
fire in an issue that is treated as 'heresy' by an intrasigent
scientific community that is simply lazy and comfortable with it's
old notions. That is a tried and true method of revolutionary
scientists who in the past knew they would be accused of heresy."
In addition to this, Michael was shown to be comprehensively wrong in
his claim that Maeve, Richard or any other member of the Leakey family
(much less Richard's apocryphal brother "Luis Jr.") had found any
pre-Lucy pelvic bones to support Michael's claim. The nearest Michael
could get was STS-14, from Sterkfontein, volunteered by John Hawks, July
1st, 1997, which according to John "presents a well-preserved innominate
bone that could be mistaken for Lucy's twin, both in size and in structure"
but has been identified as A. africanus rather than A. afarensis, making it
_post-Lucy_. This didn't stop Michael seizing these _non-Leakey_,
_post-Lucy_ remains as some kind of vindication, and further claiming that
they had "perfectly modern pelvic bones," which Lucy at least demonstrably
does not. For Michael's information, and to forestall a repetition of the
time-wasting if entertaining "post-cranial" farce, the innominate bone or
_os coxae_ is also known as the pelvic bone.
> But someone's
> opinion is not a supporting argument for a theory anyway.
Indeed, Michael's opinion, which has been demonstrated to be
comprehensively false, could not support his theory that intelligent
aliens are probably going to look human. I am pleased now that Michael
sees the error of his earlier contention.
>
> Also, while I stated that AAT was the "dominant theory",
> I also stated that in a recent poll of the Royal Society
> (not quite so recent now), 25% supported the theory and
> 75% did not. So clearly the context of the word dominant
> was not as Sherilyn has attempted to twist it into. My
> notion of what constitutes a dominant theory is not a
> function of popularity contests. Dominant theories,
> i.e. theories most supported by evidence, are often
> rejected by the overwhelming majority of scientists before
> it is eventually adopted.
This is quite true. But it was Michael himself who supported
his contention that the AAT was the dominant theory by the
following astonishing and completely false assertion:
'The "water-baby" theory was put forward by the Royal Academy of
Science almost twenty years ago and has been battling for
acceptance unntil the Leaky's find earlier this decade with
rather ended the matter.'
and also asserted falsely that it was "supported by such proponents
as the Leakys,", particularly one "Luis Leakey Jr.", and that the
hypothesis "has majority acceptance in the relevant scientific
communities."
And on the subject of evidence, a subject that I agree with Michael
should be the deciding factor in science, the evidence that Michael
claimed had "rather ended the matter" was shown not to exist.
So the AAT, like a number of other hypotheses of human origins, has
a few points going for it, and a few points against. On the evidence,
it is not the dominant theory of human evolution. And as regards
Michael's contention that Lucy or any other hominid at or about that
time had "perfectly modern pelvic bones," this has been shown to be
false. Lucy was _probably_ bipedal, but if as seems likely she was
a human ancestor, then the pelvis has evolved somewhat since Lucy,
presumably in adaptation for the upright posture. On that basis, the
modern human pelvis, with the unique attributes of which Michael made so
much, is largely a product of human evolution over the last four million
years.
>
> And once again, this is not a supporting argument, this is
> an expression of my opinion about the hypothesis (with the
> exception of the Leakey statement which I apparently can
> not recant enough for Sherilyn's satisfaction).
I will take the above as an explicit recantation of the claim
that the Leakeys or anyone else had found human remains that
"rather ended" the battle for acceptance by the AAT.
>
> > All three claims are nonsense, of course, but I have summarised
> > them accurately.
>
> She has accurately reproduced two superfluous statements,
I will accept this as an admission by Michael that he no longer
wishes to support his contentions about humanoid aliens by reference
to the AAT.
> and inaccurately referenced a third superfluous statement,
I cannot see how any of the statements could be said to be inaccurate.
All three statements were quotations from Michael's own postings
and were backed up with reference to URLs to those very postings in
the Deja News archive.
> while completely ignoring anything that could even remotely
> be considered a supporting point for the argument.
[ad hominem snipped]
This brings me to the question: since Michael no longer seems to
want to support his claims about humanoid aliens by reference to
the AAT, on what does he now propose to base those claims?
>
> > That Michael is uncomfortable with his own claims and continually
> > misrepresents my objection to them as if I were attempting to refute
> > a particular theory of human origins, well, that's his problem.
>
> Talk about misrepresentation. Such hypocrisy! I don't
> care what your opinion is, as long as you saliently
> address the argument.
Something I have consistently done. I have shown comprehensively
that all three planks of Michael's claim about humanoid aliens
were false.
> Instead you completely ignore the
> supporting arguments, time and time again, in favor of
> the kind of ridiculous rebuttal to statements that are
> utterly superfluous to the argument as you do above. And
> even at that, you repeatedly twist these superfluous
> statements out of context and perpetually refer to a
> statement that I have repeatedly recanted.
>
> As to my supposedly being uncomfortable with my own
> statements, this is her odd why of acknowledging my
> objection that these statements are not supporting
> points, and so rebuttals to them are irrelevant.
> Getting her to address ACTUAL supporting points is
> a superhuman feat that I doubt anyone is capable of.
So, sixteen-and-a-half months down the line, are we to be
presented with the _actual_ supporting arguments for Michael's
claim that intelligent, space-faring aliens are likely to be
humanoid, rather than what Michael now admits was a "superfluous",
if entertaining, detour through Michael's opinions of the AAT?
[ad hominem snipped]
--
Sherilyn
Marc Verhaegen
>Also, while I stated that AAT was the "dominant theory",
>I also stated that in a recent poll of the Royal Society
>(not quite so recent now), 25% supported the theory and
>75% did not.
That's perhaps ten times more than ten years ago. Within another ten years
the AAT, in one form or another, will be accepted by any sensible
anthropologist. We'll have to be patient...
>So clearly the context of the word dominant
>was not as Sherilyn has attempted to twist it into. My
>notion of what constitutes a dominant theory is not a
>function of popularity contests. Dominant theories,
>i.e. theories most supported by evidence, are often
>rejected by the overwhelming majority of scientists before
>it is eventually adopted.
Yes, this is not typical of anthropology, but of all sciences, see
continental drift, round earth, earth circling around sun, etc. etc. It's
incredible how stupid & conservative some apparently intelligent people can
behave.
Marc
(Michael, I liked very much what you wrote in a previous post on the linear
build in humans & penguins & aquatics.)
Sherilyn
"Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
> ...
> >Also, while I stated that AAT was the "dominant theory",
> >I also stated that in a recent poll of the Royal Society
> >(not quite so recent now), 25% supported the theory and
> >75% did not.
>
> That's perhaps ten times more than ten years ago. Within another ten years
> the AAT, in one form or another, will be accepted by any sensible
> anthropologist. We'll have to be patient...
The "recent" poll Michael refers to supposedly took place about twenty
years ago. If we can take Michael's reference as accurate (as I have
shown, I think this is somewhat debateable) then the poll preceded
by a number of years whatever popularity contest you are quoting.
It's common for advocates to see in those skeptical of their claims a
strand of obstinacy. Sometimes, as when good evidence is available
but nobody will look at it, this is justified. The AAT is a brand of
evolutionary theory known as a "just-so" story--that is to say, it's a
piece of adaptationist reasoning intended to give an explanation for
several traits; as such, its explanatory power is of less importance
in judging its validity than the evidence that can be adduced to show
that this explanation and no other is the correct one. Whilst
acknowledging that the AAT would be a particularly powerful explanation
of some traits (though not of others) I await that evidence. It is worth
noting that none of the responsible protagonists of the AAT is claiming
that such evidence has been uncovered.
--
Sherilyn
myke_r...@yahoo.com
> Michael claimed that the AAT was incontrovertible, and attempted
> to support this claim. If it were, Michael clearly reasoned, then
> simian-to-humanoid evolution was almost inevitable. And that is
> good reasoning. This kind of reasoning (using a well supported
> theory to advance an argument) is perfectly respectable and little
> science could be done without it. So Michael is wrong to claim
> that his conjecture could not prove his hypothesis.
I have never made the primate-to-humanoid assertion on
sci.anthropology. You kept attempting to bring in the more
advanced topic as a diversion from the fact that you have
never even remotely saliently addressed my argument for AAT.
There is little point in attempting to argue for a conjecture
based on AAT if one can't even get you to saliently address
the argument for AAT itself.
Only one of the supposed "supporting points" even applies to
the post-AAT conjecture. One was not a supporting argument at all,
but the actual conjecture itself! Another was a statement that is
only relevant to AAT, not the post-AAT conjecture. And the third
was simply the assertion that AAT is correct.
> > Talk about misrepresentation. Such hypocrisy! I don't
> > care what your opinion is, as long as you saliently
> > address the argument.
>
> Something I have consistently done. I have shown comprehensively
> that all three planks of Michael's claim about humanoid aliens
> were false.
You have never saliently addressed, much less rebutted my argument
for AAT. I'll re-post it at the end of this post to show the extreme
contrast between the nonsensical objections Sherilyn makes vs. my
actual argument for AAT.
> And as regards Michael's contention that Lucy or any other hominid
> at or about that time had "perfectly modern pelvic bones," this has
> been shown to be false.
Lucy was definitively fully bipedal. You attempted to argue that
she was not as efficient at locomotion, which is irrelevant to
the fact that she was definitively fully bipedal.
You perpetually take my one time statement about her pelvis being
modern, completely out of the context of being fully bipedal, no
matter how many times I attempted to assert the context of
bipedalism. You falsely claim that I asserted no changes had
occurred in 4 million years; an absurd statement which I most
definitely never even remotely made. My reference was purely in
the context of being fully bipedal vs. partially bipedal. You
attempted to suggest that Lucy was not fully bipedal, which is
simply a flat dead false assertion.
> In addition to this, Michael was shown to be comprehensively wrong in
> his claim that [has been] found any pre-Lucy pelvic bones to support
> Michael's claim.
There is no distinction between pre-Lucy findings and Lucy as far
as full bipedality goes. Another strawman argument irrelevant to my
assertions for AAT.
> This brings me to the question: since Michael no longer seems to
> want to support his claims about humanoid aliens by reference to
> the AAT, on what does he now propose to base those claims?
I made no such statement. You never know what kind of bizarre
interpretation Sherilyn will make of one's statements. I have
no desire to attempt to debate a post-AAT conjecture with
someone who is entirely unable to saliently addressed the
argument for AAT. If you can provide *one* *single* salient
criticism to the argument that follows bellow, then it might
potentially be worth while to discuss conjectures which
follow from AAT. Otherwise, it is utterly pointless.
Here it is, one more time. Take your best shot, Sherilyn. You
have never even remotely addressed my ACTUAL principle supporting
argument for AAT. Now is your chance to provide your first salient
objection to it, for which you have entirely failed to do, this
week, or at any time in the past.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
I want to repeat the concluding sentence for emphasis:
So in effect, the anti-AAT argument poses pure supposition
without evidential support as being entirely superior to
the only positively known mechanism for the development of
subcutaneos fat and straight leg-torso alignment.
Currently, the only evidence that exists definitively
supports AAT as the only means by which leg-torso
alignment and subcutaneos fat could possibly evolve.
Until evidence of another possible evolutionary path
is demonstrated, AAT is the only theory with any
meaningful, relevant evidence to support it.
Other aspects of the evidence may be unclear, but this
aspect is not: there is simply no other means known to
produce leg-torso alignment and subcutaneos fat. The
anti-AAT argument has nothing but a vacuum to offer in
this absolutely essential regard. The anti-AAT argument
has no evidence what-so-ever to suggest how leg-torso
alignment and subcutaneos fat could evolve purely on
land. By contrast, these characteristics are known to
commonly evolve among formerly non-aquatic marine
animals. So you have a vacuum of evidence vs. a very
well established and uncontestable pattern of evolution
that AAT relies on.
Any theory of human evolution which fails to adequately
address the evolution of bipedalism is utterly worthless.
That is the quentessential distinction between primates
and early hominids. Other issues can be addressed till
the cows come home, but if no evidence for how bipedalism
could have evolved is provided, then the theory has failed
to address the central issue of early hominid evolution. A
theory which says, "it just happened", is not scientific
at all; it is pure supposition without any supporting
evidence, pure opinion derived from dogma instead of
rational analysis.
Sherilyn
myke_r...@yahoo.com wrote:
> Sherilyn <Sher...@sidaway.demon.co.uk> wrote:
> > Michael claimed that the AAT was incontrovertible, and attempted
> > to support this claim. If it were, Michael clearly reasoned, then
> > simian-to-humanoid evolution was almost inevitable. And that is
> > good reasoning. This kind of reasoning (using a well supported
> > theory to advance an argument) is perfectly respectable and little
> > science could be done without it. So Michael is wrong to claim
> > that his conjecture could not prove his hypothesis.
>
> I have never made the primate-to-humanoid assertion on
> sci.anthropology.
This is simply another example of Michael's selective amnesia. Michael
has not only made this connection on s.a.p., he has also advanced his
humanoid aliens argument on this newsgroup.
June 11th, 1997:
[Richard Caldwell said:]
> As I have said before, I have no problem with [the AAT]. However, I
> fail to see what this has to do with the probable evolution of some
> intelligent alien species on another planet orbiting another star.
[Michael responded]
Because it predicts that an alien intelligence will most likely be, just
like ourselves, the first aquatic primate on their planet.
June 12th, 1997:
Prehensile fingers are unqiue to primates. The water baby theory
predicts that only a species with prehensile fingers can benefit
from the upright posture. That is the definition of primate, an
order that has prehensile fingers. Thus, AAT predicts that
only a primate like order of animal is even a canidate for
becoming a hominid.
June 13th, 1997:
[Michael quoted me:]
> : and further mischaracterized the theory as predicting that the first
> : primate to evolve into an aquatic ape would end up with a humanoid
> : appearance.
It is a direct collary of AAT. I've provided a very solid argument to
this effect, to which Sherilyn has never replied. She just insists,
"2 + 2 does not equal 4!!!!", which she has comperhensively
shown, even though she has never once addressed the argument
that I've put forward numerous times to this effect.
[To my knowledge Michael has never been able to explain why the AAT has
any bearing on this matter.]
July 15th, 1997:
[Michael quoted himself]
> My assertion is that AAT predicts that sentient beings on
> another planet would most likely evolve as bipeds with arms and
> legs.
[Michael continued]
And note, this hasn't changed, although my focus is more on
fingers.
Also the whole of the posting "Myers makes a few surprisingly coherent
statements" on September 9th, 1997, the whole of the posting "Re: Humanoid
aliens parting shot" on September 20th, 1997, and numerous other postings
in by Michael that thread.
September 30th, 1997:
[I summarised Michael's point as:
> 2) The Aquatic Ape Theory provides support for the theory that
> intelligent extraterrestrials will tend to be humanoid
[Michael's reply:]
Endoskeletal creatures have no other viable evolutionary path.
Large six legged endoskeletal creatures are not possible because
of extremely straightforward and obvious selective pressures,
detailed in other postings, without meaningful counter arguments
having been posted so far. The topic has extended to the
possibility of supra-octopoids and and supra-crustiods, if I may
coin terms for these as yet unnamed potential evolutionary paths.
Also, the whole of the posting "Re: Humans belong here", dated October
6th, 1997.
It's beside the point, in any case, since firstly Michael only raised
the AAT (in late April, 1997) in defence of his humanoid aliens claim,
and secondly I am not the rabid opponent of the AAT Michael apparently
wants me to be. I simply point out that he cannot use the AAT in
support of his humanoid aliens hypothesis.
> You kept attempting to bring in the more
> advanced topic as a diversion from the fact that you have
> never even remotely saliently addressed my argument for AAT.
Michael of course has it ass-about-face. It was Michael who
introduced the AAT into the humanoid aliens argument. I can
hardly be blamed for wishing to keep Michael off his pet
obsession and on our topic of the discussion: the likelihood
of spacetravelling aliens resembling humans. The AAT provides
absolutely no support for his contention.
> There is little point in attempting to argue for a conjecture
> based on AAT if one can't even get you to saliently address
> the argument for AAT itself.
This is Michael's way of saying he'd rather change the subject.
The AAT could be true, I have never once denied it (Michael apparently
thinks that because I oppose his argument on humanoid aliens, I should
also oppose the AAT, but this does not follow.) Michael's
three claims were that the AAT was the _dominant_ theory of human
origins, that it was _incontrovertible_, and that it _predicted_
that the eventual arrival of hominids was almost assured if a
"simian-like" animal evolved on a planet (I have emphasized the
words Michael himself used to show that I am not exaggerating his
original point).
>
> Only one of the supposed "supporting points" even applies to
> the post-AAT conjecture. One was not a supporting argument at all,
> but the actual conjecture itself! Another was a statement that is
> only relevant to AAT, not the post-AAT conjecture. And the third
> was simply the assertion that AAT is correct.
Michael himself ventured to advance a _conjecture_ as support for his
argument. It isn't my fault if his conjecture was ill-conceived.
>
> > > Talk about misrepresentation. Such hypocrisy! I don't
> > > care what your opinion is, as long as you saliently
> > > address the argument.
> >
> > Something I have consistently done. I have shown comprehensively
> > that all three planks of Michael's claim about humanoid aliens
> > were false.
>
> You have never saliently addressed, much less rebutted my argument
> for AAT.
Notice again Michael's attempt to change the subject. Excuse me while
I emphasize this:
I DO NOT DISPUTE THE AAT AS A POSSIBLE THEORY OF HUMAN ORIGINS,
NOR HAVE I EVER DISPUTED IT.
Notice that Michael now calls his AAT-humanoid aliens link a _conjecture_,
where previously he called it a prediction of the AAT).
...
>
> > And as regards Michael's contention that Lucy or any other hominid
> > at or about that time had "perfectly modern pelvic bones," this has
> > been shown to be false.
>
> Lucy was definitively fully bipedal. You attempted to argue that
> she was not as efficient at locomotion, which is irrelevant to
> the fact that she was definitively fully bipedal.
Michael argued that Lucy's pelvis was "fully modern". I never
disputed that Lucy was in all likelihood fully bipedal, though
her likely gait would best be described as "intermediate".
Certainly the morphology of her pelvis is intermediate, though
much closer to human shape than that of other modern apes (notice
again that I don't adopt the extreme position Michael would like
me to--it isn't necessary to my argument). On the origin of bipedalism,
I cited the following amongst other sources:
http://www-anthro.ucdavis.edu/faculty/mchenry/bipedal.htm
which quotes Taylor and Rowntress's experiments on modern chimpanzees
showing that, even with their non-hominid pelvises, they are
as efficient in bipedal locomotion as they are in quadrupedal
locomotion. Thus "the adoption of bipedalism by a Miocene
hominoid need not be taken as such an unlikely event, especially
given the fact that all lesser apes today are habitual bipeds and
bipedalism can easily be adopted by modern chimpanzees in the
wild."
>
> You perpetually take my one time statement about her pelvis being
> modern, completely out of the context of being fully bipedal, no
> matter how many times I attempted to assert the context of
> bipedalism.
And on the claim that Lucy was "fully modern with respect to
bipedalism," Phil Nicholls had this to say on July 13th, 1997:
"[While] hominids were fully bipedal at 4 million years ago they
differ in a number of ways from modern human bipedalism: Lucy had
shorter legs and larger feet for her body size. Here limb proportions
were somewhat between those of a bonobo (pygmie chimpanzee) and modern
human. Also the angles on the acetabula (the socket for the head of
the femur [thigh bone]) are at a slightly different angle from modern
hominids. There is also a curvature to the fingers that is a
characteristic of arboreal primates. Lucy may have waddled a bit
when she walked and took to the trees during times of danger or to
sleep."
So no, Lucy didn't have a fully modern pelvis, and no, Lucy wasn't
"fully modern" with respect to bipedalism. She shows signs of being
adapted to bipedalism. There is no suggestion of a discontinuity
between the miocene ancestral ape, Lucy and homo sapiens with respect to
bipedalism: all three could walk on two legs, just as most modern lesser
apes, and chimpanzees and bonoboes, can do.
> You falsely claim that I asserted no changes had
> occurred in 4 million years; an absurd statement which I most
> definitely never even remotely made.
I truthfully quoted Michael's repeated statement that
australopithecine pelvises were "fully modern." That Michael then
had to enter cavils and accuse me of misinterpretation is entirely
his fault.
> My reference was purely in
> the context of being fully bipedal vs. partially bipedal. You
> attempted to suggest that Lucy was not fully bipedal, which is
> simply a flat dead false assertion.
I have at no time stated that australopithecus was not fully
bipedal. The question is not the mode of locomotion, but the
gait and its efficiency.
>
> > In addition to this, Michael was shown to be comprehensively wrong in
> > his claim that [has been] found any pre-Lucy pelvic bones to support
> > Michael's claim.
>
> There is no distinction between pre-Lucy findings and Lucy as far
> as full bipedality goes. Another strawman argument irrelevant to my
> assertions for AAT.
Michael was told repeatedly by a number of different people that there
are no pre-Lucy pelvic remains, therefore the above claim that "there is
no distinction between pre-Lucy findings and Lucy as far as full bipedality
goes" is meaningless.
>
> > This brings me to the question: since Michael no longer seems to
> > want to support his claims about humanoid aliens by reference to
> > the AAT, on what does he now propose to base those claims?
>
> I made no such statement.
This is a lie; I showed in recent postings that the AAT subject
surfaced as Michael's defence of his position in the humanoid aliens
debate, and at the beginning of this posting I showed that he has
repeatedly returned and stated that ape-humanoid evolution is a predicted
outcome of the AAT, and that this has relevance to hypothetical (for most
of us, at least) spacetravelling extraterrestrial life.
>
> Here it is, one more time. Take your best shot, Sherilyn. You
> have never even remotely addressed my ACTUAL principle supporting
> argument for AAT.
As have never disputed the AAT, but rather Michael's argument linking the
AAT to his statements about humanoid aliens, it would be superfluous to
address these arguments. I confined myself to correcting Michael's many,
many misstatements of the AAT and its implicaitons. Michael can no longer
hide behind the AAT.
--
Sherilyn
Alan DeKok
Welcom back, Michael. It's nice to see your basic discussion style
hasn't changed.
In article <6tq5n0$sed$1...@nnrp1.dejanews.com>, <myke_r...@yahoo.com> wrote:
...
>There is little point in attempting to argue for a conjecture
>based on AAT if one can't even get you to saliently address
>the argument for AAT itself.
...
>You have never saliently addressed, much less rebutted my argument
>for AAT.
...
>I made no such statement. You never know what kind of bizarre
>interpretation Sherilyn will make of one's statements. I have
>no desire to attempt to debate a post-AAT conjecture with
>someone who is entirely unable to saliently addressed the
>argument for AAT. If you can provide *one* *single* salient
>criticism to the argument that follows bellow, then it might
>potentially be worth while to discuss conjectures which
>follow from AAT. Otherwise, it is utterly pointless.
>
>Here it is, one more time. Take your best shot, Sherilyn. You
>have never even remotely addressed my ACTUAL principle supporting
>argument for AAT. Now is your chance to provide your first salient
>objection to it, for which you have entirely failed to do, this
>week, or at any time in the past.
Lest anyone be tempted to take you up on the offer, I'll suggest that
they check Dejanews first, for back posts. No matter what you say,
Michael will accuse you of being "incoherent", of "never addressing his
arguments", etc.
I guess since Glen stopped posting so much, it's time for Michael to
come back.
Alan DeKok.
Sherilyn
aland@z[achilles].net (Alan DeKok) wrote:
>
> Welcom back, Michael. It's nice to see your basic discussion style
> hasn't changed.
>
> In article <6tq5n0$sed$1...@nnrp1.dejanews.com>, <myke_r...@yahoo.com>
> wrote:
...
> >have never even remotely addressed my ACTUAL principle supporting
> >argument for AAT. Now is your chance to provide your first salient
> >objection to it, for which you have entirely failed to do, this
> >week, or at any time in the past.
>
> they check Dejanews first, for back posts. No matter what you say,
> Michael will accuse you of being "incoherent", of "never addressing his
> arguments", etc.
I did respond to an early cut of Michael's arguments for the AAT, simply
to point out the glaring flaws in his reasoning. The first posting, June
3rd, 1997, never made it to Deja News, for some reason, but I reposted it
two days later, and quoted it in its entirety in a June 13th posting when
Michael refused to look up the original posting on Deja News. Here it is
again, just to show that Michael is wrong again when he claims I have not
addressed his peculiar interpretation of the AAT. I have no idea if he has
recanted any of the points I responded to here back in early June, 1997,
added to them, or modified the list in any other way. I advance this repost
simply to document the dismaying course of Michael's continued selective
amnesia.
Elsewhere, I have a copy of a posting in which Michael comprehensively
flamed one of his own earlier postings. That may get another airing,
if only because it's so funny to see Michael himself getting the Reynolds
treatment.
[BEGIN REPOST]
>Re: AAT, mating behavior, diving (was DeKok goes
>ballistic (again))
>From "Michael Reynolds" <mrey...@symantec.com>
>Organization Sequent
>Date 3 Jun 1997 20:54:34 GMT
>Newsgroups alt.paranet.ufo,sci.skeptic,talk.origins
>Message-ID <01bc7060$25328350$718f409b@mreynol_nt4>
Michael is still under the impression that I object to the AAT rather
than his misrepresentation of it. However, this is good practice at
playing devil's advocate.
>1) If human beings are not semi-aquatic, then primate is the only order
>of mammal without an aquatic member.
>
>2) If humans are not semi-aquatic, then we are the only example in all
>of nature of a non-aquatic animal that has developed straightened hips.
As I remarked earlier, these are observations and not arguments. Nature
is not obliged to observe Michael's wish for symmetry. There are good
reasons to think that humans developed _near_ water (we swim well) but
the evidence that humans developed from an aquatic ape is less
compelling than Michael thinks (and, tragically for Michael's case, the
AAT doesn't imply what he believes it does about parallel evolution--if
the AAT is true, it means humans are the unique product of an aborted
aquatic adaptation amongst apes.)
>3) Our ancestors were the only Savannah animals, and the only primates
>to evolve sweating as a cooling mechanism. Sweating could not have
>developed on the African Savannah where water conservation is at a
>premium.
To understand this you have to realise that Michael believes there are
only two possibilities: aquatic apes or savannah dwellers. By Savannah
here, Michael apparently means an arid treeless plain occupied by low
scrub of the kind that occupies much of Africa today.
I do not believe I have seen Michael advance an explanation of the
adaptation of sweating for cooling in humans. Why would an aquatic
animal need to cool down?
>4) The vast majority of the time, belly to belly mating only evolves as
>a result of hip straightening in aquatic animals.
Not really. Whales, dolphins and porpoises did not develop straight
hips (and they still _do_ have hips), their tails are true tails and not
adapted hind legs. Their actual hind legs turned into a kind of arm and
then were selected out. Amongst semi-aquatic animals, neither the polar
bear nor the hippopotamus shows any sign of hip-straightening.
>5) Breath control was essential in the evolution of speach, and no
>other primate has the breath control that humans have. Breath control
>is a requirement of aquatic adaptation.
It's a requirement of swimming, too. We'll get onto that.
>6) There is only one other primate in the entire order which can
>tollerate the submersion of the nose, and the other example is an
>island monkey which can swim from island to island.
The wonderful thing about discussing something with Michael is that he
willingly provides you with counter-examples, under the impression that
he is reinforcing his argument.
I'll assume for now that Michael will supply a citation for this in his
next post. Now is Michael going to dare to suggest that this monkey is
therefore an "aquatic ape"? I suppose it is in the sense that it
apparently possesses an adaptation predicted by the AAT. Ah, but does
it have straighter hips than the bonobo, which is believed to be our
closest relative?
So here Michael has convinced me that the ancestors of humans learned to
swim. I knew that already, of course. That doesn't make them aquatic
apes, else we would class dogs as aquatic animals also.
>7) Infants can be water trained to swim with increadible agility. Water
>babies can swim as quick and strong as most young adults.
My son was such a "water baby".
Dogs don't need training. I have already sent Michael a copy of this:
'The Newfoundland has a broad, massive head; small, deeply set, dark-
brown eyes; small ears lying close to the head; a deep chest; a dense,
water-resistant double coat, usually dull black in color; and a broad,
strong tail. The feet are large, strong, and webbed, for traversing
marshlands and shores. Powerful swimmers, Newfoundlands are known to
have rescued human beings from drowning and to have carried lifelines
from shore to ships in distress.'
[excerpt]
"Newfoundland (dog)," Microsoft (R) Encarta.
Copyright (c) 1994 Microsoft Corporation.
Copyright (c) 1994 Funk & Wagnall's Corporation.
Truly a set of feats only a very powerful swimmer could achieve.
>8) Humans can partially constrict their nostrals, which is a uniquely
>aquatic adaptation. Some land animals can flare their nostrals for the
>purposes of taking more air for the olfactory sense, but they can not
>restrict the flow, which only develops as a result of the need to keep
>out water.
I have attempted this. It didn't work. No matter how much I
constricted my nostrils, the net effect on the entry of water into my
nose was nil. Labelling something an aquatic adaptation doesn't make it
so.
The nose can be used as a form of signal, making human faces almost
uniquely expressive in the animal kingdom. Perhaps this is evidence
that signalling started early in humans, even before the development of
proper speech.
>9) Hair loss is most often associated with aquatic adaptation. While
>some semi-aqautic mammals retain fur (no fully aquatic mammals do),
>there are vanishingly few examples of non-aquatic mammals loosing their
>fur. Rhinos and hairless moles are the only counter examples I can
>think of.
Hair loss? Check your skin, Michael. I checked mine and yes, I am
covered all over in fine hairs. Sexual selection can account for this.
Just because an adaptation is present in some aquatic animals doesn't
mean it is necessary or a sufficient evidence of aquatic adaptation in
another.
Fur seals and polar bears do not have hairless skins. Nor, for that
matter, do pachiderms, but fully aquatic animals tend to develop a form
of streamlined hide that aids their movement through the water. I'm not
sure, but perhaps the hippopotamus has an adaptation like this. It is
far removed from the soft, sensitive, hairy human skin.
...
>10) The water baby theory accounts for the missing link: 10,000,000
>years between 4 and 14 million years ago, in which no fossil record of
>our ancestors exists. Sea shore conditions are extremely unfavorable
>for the formation of fossils and the period matchs the end of the ice
>age before last and the start of the last ice age. During this
>continuous warm period, the higher sea levels trapped our ancestors on
>islands off the coast of south eastern Africa.
Here Michael excels himself. Up to now, the absence of fossils in _all_
apes for that period has been blamed on the conditions of the forest
floor. In steps Michael and "sea shore conditions are extremely
unfavorable for the formation of fossils". Of course this does not
account for the absence of fossils of other apes. I am also skeptical
of Michael's claim. Aquatic animals that sink when they die make very
good fossils, and conditions are very good only a few hundred feet from
the shore.
>11) Pre-Lucy remains have only been found in exactly the location
>predicted by the water baby theory in south eastern Africa.
In other words, in areas known to have been damp at the time. Finding
fossils on an old lake or sea shore or river bed is easy--that's where
most fossils are made. It would be extraordinary if fossils were found
anywhere else--on areas known to have been arid and waterless, for
instance.
>Sherilyn has stated that AAT does not predict parallel evolution
>because it describes an event that is somehow "unusual". In fact quite
>the reverse is true. In case after case, if we are not aquatic, *THAT*
>creates a very unusual circumstance, even utterly unique; where as, if
>we are aquatic, we fit a very large scale consistent pattern with two,
>one or no counter examples. There are two poimts for which, if we are
>not aquatic, then we are utterly unique in all of the animal kingdom;
>one point where, if we are not aquatic, we are utterly unique in all of
>the class of mammal; and four more points where, the alternate non-
>aquatic examples to the large scale consistent aquatic pattern, can be
>counted on one hand.
What Michael is trying to say here, I think, is that if we are not
aquatic then it would hurt his sense of symmetry because we would be
members of the only order of animal without an aquatic member (it's not
remotely true, as far as I know). He uses the same argument "in case
after case", as I have shown, to try to shoehorn us into the aquatic
corner. Well, we could be descended from aquatic semi-adaptations, but
the evidence is not strong. Some of the aquatic adaptation he has cited
are clearly useless in the water (sweating and the nose, for instance).
Now the problem with Michael's thesis, which is that the AAT predicts
that the first [great ape] to develop an aquatic adaptation would
develop human characteristics, is simply this: it predicts no such
thing. It simply looks at human characteristics and claims that these
characteristics could not have developed _without_ an aborted aquatic
phase. Just as going into the trees didn't turn the ancestors of the
squirrels into monkeys, going into the water didn't turn the seal's
ancestor into a cetacean (they retained their legs and lost their
original tails). The AAT can only tell you, if it's true, that
Michael's original claim that the human appearance in reports of ET
greys can be accounted for by parallel evolution of ape-like creatures
(a questionable assumption in itself), is in fact wider of the beam it
appears even at first--they'd look more like bonoboes than humans,
_unless_ they went into the water and then came out (the baptism
significance isn't lost on me).
>I need to give credit where credit is due, Sherilyn has effectively
>countered one of the points for APT, which I have removed from the
>list.
>Sherilyn also correctly points out the rare exceptions to aquatic belly
>to belly mating, and finally, she pointed out an error in my statement
>of point #1 in e-mail, which I have corrected here.
Michael has yet to point out what is unusual about humans, the second
nearest cousin of the belly-to-belly mating bonobo and the front-to-back
mating chimpanzee, mating in both ways, nor has he acknowledged the
photograph of apparent belly-to-belly mating in Macaques which is in
Desmond Morris's Animalwatching.
[END OF REPOST]
--
Sherilyn
Elaine Morgan
>As a layman in anthropology, I am unclear as to the
>nature of the argument that asserts that fossil remains
>can not be associated with the location where they were
>found. In specific instances certainly, but as a
>general rule? It seems to me that if fossil remains
>are consistently found near what was a shore at the
>time of the creature's life, that this could no longer
>be subject to an objection of anomalous fossil drifting?
The strength of the objection (I have frequently pinted out its
weaknesses) lies in the fact that the fossil remains of other mammals
are also found (more or less exclusively) in wet places, and some of
them are the predecessors of species that are clearly not aquatic
e.g.baboons and giraffes. The danger of the "taxonomic bias"
argument is that when fossil hunters found hominids with fish and
turtles and crocodiles they did not think "Aha! water". They had been
trained to ignore the evidence of water. It got close, as you suggest,
to the knee-jerk assumption that fossils could "not be associated with
the location in which they were found "
Elaine
Marc Verhaegen
Sherilyn heeft geschreven in bericht <6tpici$7qv$1...@nnrp1.dejanews.com>...
...
>acknowledging that the AAT would be a particularly powerful explanation
>of some traits (though not of others) I await that evidence. It is worth
>noting that none of the responsible protagonists of the AAT is claiming
>that such evidence has been uncovered.
>--
No?
All the evidence is there, please open your eyes.
If you mean fossil evidence:
1) anatomical evidence: H.erectus, eg, if full of (ex)aquatic features:
linear build, ear exostoses, dense bones...
2) paleo-environmental evidence: All hominids are found in "wet"
environments, there is no evidence whatsoever for a savanna milieu.
H.erectus esp. is often found in seacoasts & river deltas, although inland
fossilisation (riverine, lacustrine...) is much more probable. Do you want
me to send my list?
Marc
Marc Verhaegen
myke_r...@yahoo.com heeft geschreven in bericht
<6tq5n0$sed$1...@nnrp1.dejanews.com>...
>Sherilyn <Sher...@sidaway.demon.co.uk> wrote:
>
>Lucy was definitively fully bipedal. You attempted to argue that
>she was not as efficient at locomotion, which is irrelevant to
>the fact that she was definitively fully bipedal.
>
"arboreal" adaptations, eg, curved phalanges, toeing-in of feet, small
femoral heads, mobile knee & ankle joints, low lumbosacral angle...
Marc
Marc Verhaegen
Sherilyn heeft geschreven in bericht <6trodj$l46$1...@nnrp1.dejanews.com>...
>>1) If human beings are not semi-aquatic, then primate is the only order
>>of mammal without an aquatic member.
>>
Exaggeration.
(Besides: Primates are arboreal. Are arboreals as prone to becoming aquatic
as terrestrials are?)
...
>I do not believe I have seen Michael advance an explanation of the
>adaptation of sweating for cooling in humans. Why would an aquatic
>animal need to cool down?
>
For cooling down on land.
Fully aquatics (cetaceans & sirenians) don't have sweat glands.
Some semi-aquatic do. Furseals on landuse the eccrine sweat glands on their
(hairless) hind flippers to cool down, like humans on land use the eccrine
sweat glands on our (hairless) body to cool down.
>The nose can be used as a form of signal, making human faces almost
>uniquely expressive in the animal kingdom. Perhaps this is evidence
>that signalling started early in humans, even before the development of
>proper speech.
>
Sherilyn, such "unique" explanations are anthropocentric & therefore IMO not
allowed.
We have to use the comparative evidence. The most humanlike nose is seen in
proboscis monkeys. Other mammals with external noses are: elephants, tapirs,
suids, sea elephants, hooded seals.
>
>>9) Hair loss is most often associated with aquatic adaptation. While
>>some semi-aqautic mammals retain fur (no fully aquatic mammals do),
>>there are vanishingly few examples of non-aquatic mammals loosing their
>>fur. Rhinos and hairless moles are the only counter examples I can
>>think of.
>
>Hair loss? Check your skin, Michael. I checked mine and yes, I am
>covered all over in fine hairs. Sexual selection can account for this.
>
No, Sherilyn, no "unique" explanations please. If sexual selection accounted
for that, cats & zebras should be furless too.
>Just because an adaptation is present in some aquatic animals doesn't
>mean it is necessary or a sufficient evidence of aquatic adaptation in
>another.
>
Yes, furlessness is not enough as explanation, although 95% of furless
species are fully or strongly aquatic.
Its the combination of several human characters that independently favour a
(semi)aquatic explanation that statictically proves our (semi)aqatic past.
For instance, all mammals with the combination of furlessness & thick SC fat
are aquatic.
Humans are not aquatic & are no exception to that rule, because most humans
wear cloths. In fact, we take off our cloths when going into the water.
>
>>10) The water baby theory accounts for the missing link: 10,000,000
>>years between 4 and 14 million years ago, in which no fossil record of
>>our ancestors exists. Sea shore conditions are extremely unfavorable
>>for the formation of fossils and the period matchs the end of the ice
>>age before last and the start of the last ice age. During this
>>continuous warm period, the higher sea levels trapped our ancestors on
>>islands off the coast of south eastern Africa.
>
>Here Michael excels himself. Up to now, the absence of fossils in _all_
>apes for that period has been blamed on the conditions of the forest floor.
There are lots of fossil apes: australopiths, sivapiths, gigantopith.
All gracile australopiths have been found in forested areas.
> In steps Michael and "sea shore conditions are extremely
>unfavorable for the formation of fossils". Of course this does not
>account for the absence of fossils of other apes. I am also skeptical
>of Michael's claim. Aquatic animals that sink when they die make very
>good fossils, and conditions are very good only a few hundred feet from
>the shore.
>
>>11) Pre-Lucy remains have only been found in exactly the location
>>predicted by the water baby theory in south eastern Africa.
>
>In other words, in areas known to have been damp at the time. Finding
>fossils on an old lake or sea shore or river bed is easy--that's where
>most fossils are made. It would be extraordinary if fossils were found
>anywhere else--on areas known to have been arid and waterless, for
>instance.
>
Not one instance of arid & waterless hominid paleomilieus, not even in the
air-fall & wind-blown sediments, where most Laetoli fossils are found
(fossils of colobine monkeys were abundant, ie, forest-living primates).
Some examples of australopith or early Homo milieus:
- Hadar AL.333 A. afarensis: ‘The bones were found in swale-like features
[…] it is very likely that they died and partially rotted at or very near
this site […] this group of hominids was buried in streamside gallery
woodland’ (Radosevich et al., 1992).
- Makapan A. africanus: ‘[…] very different conditions from those prevailing
today. Higher rainfall, fertile, alkaline soils and moderate relief
supported significant patches of sub-tropical forest and thick bush, rather
than savannah. Taphonomic considerations […] suggest that sub-tropical
forest was the hominins’ preferred habitat rather than grassland or
bushveld, and the adaptations of these animals was therefore fitted to a
forest habitat’ (Rayner et al., 1993; see also Reed, 1993; and Wood, 1993).
- Chesowanja A. boisei: ‘The fossiliferous sediments were deposited in a
lagoon […] Abundant root casts […] suggest that the embayment was flanked by
reeds and the presence of calcareous algae indicates that the lagoon was
warm and shallow. Bellamya and catfish are animals tolerant of relatively
stagnant water, and such situation would also be suitable for turtles and
crocodiles’ (Carney et al., 1971).
- Olduvai middle Bed I: A. boisei O.H.5 as well as habilis O.H.7 and O.H.62
were found in the most densely vegetated, wettest condition, with the
highest lake levels (Walter et al., 1991), near ostracods, freshwater
snails, fish, and aquatic birds (Conroy, 1990); ‘[…] the middle Bed-I faunas
indicate a very rich closed woodland environment, richer than any part of
the present-day savanna biome in Africa […] (Fernández-Jalvo et al., 1998).
[…] swamp vegetation is indicated by abundant vertical roots channels and
casts possibly made by some kind of reed. Fossil rhizomes of papyrus also
suggest the presence of marshland and/or shallow water’ (Conroy, 1990).
- Turkana Boy KNM-WT 15000 H. erectus: ‘Mammalian fossils are rare at this
locality, the most abundant vertebrate fossils being parts of small and
large fish. The depositional environment was evidently an alluvial plain of
low relief […] Typical lacustrine forms (for example, ostracods, molluscs)
could invade the area […] The only other fauna found so far in the
fossiliferous bed are many opercula of the swamp snail Pila, a few bones of
the catfish Synodontis and two fragments of indeterminate large mammal bone
[…]’ (Brown et al., 1985).
Marc
Matt Silberstein
<Marc.Ve...@village.uunet.be>:
>
[snip]
>
>>The nose can be used as a form of signal, making human faces almost
>>uniquely expressive in the animal kingdom. Perhaps this is evidence
>>that signalling started early in humans, even before the development of
>>proper speech.
>>
>Sherilyn, such "unique" explanations are anthropocentric & therefore IMO not
>allowed.
>We have to use the comparative evidence. The most humanlike nose is seen in
>proboscis monkeys. Other mammals with external noses are: elephants, tapirs,
>suids, sea elephants, hooded seals.
>
Yet some of those do not seem aquatic. What is your point?
>
>
>>
>>>9) Hair loss is most often associated with aquatic adaptation. While
>>>some semi-aqautic mammals retain fur (no fully aquatic mammals do),
>>>there are vanishingly few examples of non-aquatic mammals loosing their
>>>fur. Rhinos and hairless moles are the only counter examples I can
>>>think of.
>>
>>Hair loss? Check your skin, Michael. I checked mine and yes, I am
>>covered all over in fine hairs. Sexual selection can account for this.
>>
>No, Sherilyn, no "unique" explanations please. If sexual selection accounted
>for that, cats & zebras should be furless too.
>
Sexual selection is certainly not unique to this case nor does it
follow that because it was sexually selected in one case, it was so
selected in all.
>>Just because an adaptation is present in some aquatic animals doesn't
>>mean it is necessary or a sufficient evidence of aquatic adaptation in
>>another.
>>
>Yes, furlessness is not enough as explanation, although 95% of furless
>species are fully or strongly aquatic.
References please? And what % of aquatic mammals are hairless? (I have
to assume you were not including fish in your count of species.)
[snip]
Matt Silberstein
-----------------------------
"Well, art is art, isn't it? Still, on the other hand, water is water!
And east is east, and west is west, and if you take cranberries and stew them
like applesauce they taste much more like prunes than rhubarb does.
Now, uh.....Now you tell me what you know."
Julius Marx
Matt Silberstein
<Sher...@sidaway.demon.co.uk>:
[snip]
>
>[BEGIN REPOST]
>
>>Re: AAT, mating behavior, diving (was DeKok goes
>>ballistic (again))
>>From "Michael Reynolds" <mrey...@symantec.com>
>>Organization Sequent
>>Date 3 Jun 1997 20:54:34 GMT
>>Newsgroups alt.paranet.ufo,sci.skeptic,talk.origins
>>Message-ID <01bc7060$25328350$718f409b@mreynol_nt4>
>
[snip]
>>9) Hair loss is most often associated with aquatic adaptation. While
>>some semi-aqautic mammals retain fur (no fully aquatic mammals do),
>>there are vanishingly few examples of non-aquatic mammals loosing their
>>fur. Rhinos and hairless moles are the only counter examples I can
>>think of.
>
>Hair loss? Check your skin, Michael. I checked mine and yes, I am
>covered all over in fine hairs. Sexual selection can account for this.
>
>Just because an adaptation is present in some aquatic animals doesn't
>mean it is necessary or a sufficient evidence of aquatic adaptation in
>another.
Rhinos and elephants have less hair than most mammals. Therefore
rhinos and elephants evolved in the ocean. Otters and seals and sea
lions have dense fir. Therefore they are not aquatic. Do I have this
right?
>Fur seals and polar bears do not have hairless skins. Nor, for that
>matter, do pachiderms, but fully aquatic animals tend to develop a form
>of streamlined hide that aids their movement through the water. I'm not
>sure, but perhaps the hippopotamus has an adaptation like this. It is
>far removed from the soft, sensitive, hairy human skin.
>...
>
[snip]
>
>What Michael is trying to say here, I think, is that if we are not
>aquatic then it would hurt his sense of symmetry because we would be
>members of the only order of animal without an aquatic member (it's not
>remotely true, as far as I know).
The aquatic rodent is a wily beast and very shy of man.
[snip]
>[END OF REPOST]
Marc Verhaegen
<3609cdcc...@nntp.ix.netcom.com>...
>>>The nose can be used as a form of signal, making human faces almost
>>>uniquely expressive in the animal kingdom. Perhaps this is evidence
>>>that signalling started early in humans, even before the development of
>>>proper speech.
>>>
>>Sherilyn, such "unique" explanations are anthropocentric & therefore IMO
not
>>allowed.
>>We have to use the comparative evidence. The most humanlike nose is seen
in
>>proboscis monkeys. Other mammals with external noses are: elephants,
tapirs,
>>suids, sea elephants, hooded seals.
>>
>Yet some of those do not seem aquatic. What is your point?
>>
Elephants cross rivers with only the probiscis above the water surface.
Proboscis monkeys swim with their noses up, as far as possible above the
water surface.
The suids are an exception, but have no real external nose (for digging in
the ground?).
>>Yes, furlessness is not enough as explanation, although 95% of furless
species are fully or strongly aquatic.
>
>References please?
In 1985 (Med.Hypoth.16:17) I counted all the furless mammalian species (95%)
and genera (90%). Easy to verify. The furless "terrestrials" were, AFAIR, 2
elephant species, 2 rhino species, naked bat, naked mole rat.
>And what % of aquatic mammals are hairless?
I didn't counted these. You could do that & let me know the answer.
(That's not so simple: all small mammals, whether aquatic or not, are
furred, and there are a lot of them.)
As for the medium-sized mammals, all non-tropical semi-aquatics are furred.
The explanation seems to be simple: they need the fur for thermoregulation
on land. All pinnipeds have fur, except the very big adult male Steller
sealions, walruses & elephant seals.
Marc
Matt Silberstein
<Marc.Ve...@village.uunet.be>:
>Matt Silberstein heeft geschreven in bericht
><3609cdcc...@nntp.ix.netcom.com>...
>
>>>>The nose can be used as a form of signal, making human faces almost
>>>>uniquely expressive in the animal kingdom. Perhaps this is evidence
>>>>that signalling started early in humans, even before the development of
>>>>proper speech.
>>>>
>>>Sherilyn, such "unique" explanations are anthropocentric & therefore IMO
>not
>>>allowed.
>>>We have to use the comparative evidence. The most humanlike nose is seen
>in
>>>proboscis monkeys. Other mammals with external noses are: elephants,
>tapirs,
>>>suids, sea elephants, hooded seals.
>>>
>>Yet some of those do not seem aquatic. What is your point?
>>>
>Elephants cross rivers with only the probiscis above the water surface.
>Proboscis monkeys swim with their noses up, as far as possible above the
>water surface.
>The suids are an exception, but have no real external nose (for digging in
>the ground?).
>
Ok, so what is your point? Are you claiming that the elephant is an
(semi-) aquatic animal? If so, you seem to have redefined the term.
>
[unmarked snip here]
>
>>>Yes, furlessness is not enough as explanation, although 95% of furless
>species are fully or strongly aquatic.
>>
>>References please?
>
>In 1985 (Med.Hypoth.16:17) I counted all the furless mammalian species (95%)
>and genera (90%). Easy to verify. The furless "terrestrials" were, AFAIR, 2
>elephant species, 2 rhino species, naked bat, naked mole rat.
>
So the hippo counts as aquatic, but the elephant does not.
BTW, what value is there in counting species? How does a % here tell
you anything? Why is it meaningful that there are, for example, 10
species in small niches vs. one in a large one?
>>And what % of aquatic mammals are hairless?
>
>I didn't counted these. You could do that & let me know the answer.
>(That's not so simple: all small mammals, whether aquatic or not, are
>furred, and there are a lot of them.)
>
Well, not, that is not true. But so? You are the one making a claim,
you should be looking for this evidence. If the % are to mean
anything, you need this figure. It seems to me that some aquatic
mammals are furred and some furless. Some non-aquatic mammals are
furred and some furless. So the fur does not mean much either way.
>As for the medium-sized mammals, all non-tropical semi-aquatics are furred.
>The explanation seems to be simple: they need the fur for thermoregulation
>on land. All pinnipeds have fur, except the very big adult male Steller
>sealions, walruses & elephant seals.
>
So this does not do much for your argument, does it?
Sherilyn
"Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
>
> Sherilyn heeft geschreven in bericht <6trodj$l46$1...@nnrp1.dejanews.com>...
>
> >>1) If human beings are not semi-aquatic, then primate is the only order
> >>of mammal without an aquatic member.
> >>
> Exaggeration.
Agreed. Michael's argument was an exaggeration.
>
> ...
> >I do not believe I have seen Michael advance an explanation of the
> >adaptation of sweating for cooling in humans. Why would an aquatic
> >animal need to cool down?
> >
> For cooling down on land.
Reasonable, though this is conjecture, and other primates do have sweat
glands. If modern humans need more sweat glands (we do, after all, have
radically different lifestyles than most apes, and we don't know how
recent the widespread sweat glands are) then an aquatic phase would be
superfluous.
...
>
> >The nose can be used as a form of signal, making human faces almost
> >uniquely expressive in the animal kingdom. Perhaps this is evidence
> >that signalling started early in humans, even before the development of
> >proper speech.
> >
> Sherilyn, such "unique" explanations are anthropocentric & therefore IMO not
> allowed.
> We have to use the comparative evidence. The most humanlike nose is seen in
> proboscis monkeys. Other mammals with external noses are: elephants, tapirs,
> suids, sea elephants, hooded seals.
I strongly disagree with your suggestion. The only _evidence_ that would
really be acceptable here would be that which can rule out one or other
just-so story. You don't like mine, I'm not so sure about Michael's.
They have one thing in common: nobody knows the truth.
>
> >
> >>9) Hair loss is most often associated with aquatic adaptation. While
> >>some semi-aqautic mammals retain fur (no fully aquatic mammals do),
> >>there are vanishingly few examples of non-aquatic mammals loosing their
> >>fur. Rhinos and hairless moles are the only counter examples I can
> >>think of.
> >
> >Hair loss? Check your skin, Michael. I checked mine and yes, I am
> >covered all over in fine hairs. Sexual selection can account for this.
I should of course have said "could". It's a devil's advocate position.
> >
> No, Sherilyn, no "unique" explanations please. If sexual selection accounted
> for that, cats & zebras should be furless too.
And peacock's tails cannot possibly be due to sexual selection, otherwise
all male birds would have enormous tails.
http://www.sidaway.demon.co.uk/skeptic/toolkit.html
Nice troll, Marc. You had me going, there.
Sherilyn
"Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
>
> Sherilyn heeft geschreven in bericht <6tpici$7qv$1...@nnrp1.dejanews.com>...
> ...
> >acknowledging that the AAT would be a particularly powerful explanation
> >of some traits (though not of others) I await that evidence. It is worth
> >noting that none of the responsible protagonists of the AAT is claiming
> >that such evidence has been uncovered.
> >--
> ???
> No?
>
> All the evidence is there, please open your eyes.
> If you mean fossil evidence:
> 1) anatomical evidence: H.erectus, eg, if full of (ex)aquatic features:
> linear build, ear exostoses, dense bones...
I'm afraid it's simply conjecture at this stage to attribute specific
traits, as you apparently wish to do, to aquatic adaptation. I agree
that it would be nice if we could pin it down neatly, but I do think some
evidence would be required, not just nice neat stories. I do get
suspicious when people say "B is like C, A caused C, therefore A caused
B." That isn't evidence, it's speculation.
> 2) paleo-environmental evidence: All hominids are found in "wet"
> environments,
Tthe _fossils_ are found in wet environments. That's where fossils are
made, generally. Somebody did recently mention some rare wind-blown
fossilization in an arid environment that doesn't seem to match your
above statement (apologies if I misread the posting). And once again,
simply living by the sea shore or near a lake is not evidence of aquatic
or semi-aquatic adaptation. They'd have to be pretty much up to their
necks most of the time, and in that case I'd be inclined to ask: where
are the fossils? I would expect many more than have been found.
>there is no evidence whatsoever for a savanna milieu.
I'm not sure what the above non sequitur is doing in a discussion of
whether humans were adapted to an aquatic existence. Is this an example
of a false dichotomy?
> H.erectus esp. is often found in seacoasts & river deltas, although inland
> fossilisation (riverine, lacustrine...) is much more probable. Do you want
> me to send my list?
I think you posted it a few times already, but I'm still puzzled. Why do
you think that a fondness for a seaside and estuary existence in H. erectus
means his mocene or australopithecine ancestor must have been partially
adapted for aquatic or semi-aquatic existence? I accept that he could
have been, but the evidence is ambiguous, to put it mildly.
--
Sherilyn
Sherilyn
"Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
>
> myke_r...@yahoo.com heeft geschreven in bericht
> <6tq5n0$sed$1...@nnrp1.dejanews.com>...
> >Sherilyn <Sher...@sidaway.demon.co.uk> wrote:
I wrote none of what you quoted; I can't be the only person who
had to look twice to check this. Please be careful with your
attributions.
[Michael]
> >
> >Lucy was definitively fully bipedal. You attempted to argue that
> >she was not as efficient at locomotion, which is irrelevant to
> >the fact that she was definitively fully bipedal.
[Marc]
> Lucy certainly was not bipedal in "our" sense. He/she/it had a lot of
> "arboreal" adaptations, eg, curved phalanges, toeing-in of feet, small
> femoral heads, mobile knee & ankle joints, low lumbosacral angle...
>
> Marc
>
>
-----== Posted via Deja News, The Leader in Internet Discussion ==-----
Sherilyn
mat...@ix.netcom.com (Matt Silberstein) wrote:
> In sci.skeptic I read this message from Sherilyn
> <Sher...@sidaway.demon.co.uk>:
[repost from years and years ago]
> >What Michael is trying to say here, I think, is that if we are not
> >aquatic then it would hurt his sense of symmetry because we would be
> >members of the only order of animal without an aquatic member (it's not
> >remotely true, as far as I know).
>
> The aquatic rodent is a wily beast and very shy of man.
I believe the shyness of aquatic bats was also mentioned.
...
Lorenzo L. Love
Matt Silberstein wrote:
> In sci.skeptic I read this message from Sherilyn
> <Sher...@sidaway.demon.co.uk>:
>
> >What Michael is trying to say here, I think, is that if we are not
> >aquatic then it would hurt his sense of symmetry because we would be
> >members of the only order of animal without an aquatic member (it's not
> >remotely true, as far as I know).
>
> The aquatic rodent is a wily beast and very shy of man.
>
> [snip]
>
> >[END OF REPOST]
>
> Matt Silberstein
One of the few semi-aquatic animals in the same weight range as the early
hominines is the largest living rodent, the capybara. And of course like all
small and medium sized aquatics and semi-aquatics, it has a nice coat of fur. And
then there are other aquatic rodents like musk rats, beavers and nutrias, all
well known for their thick fur coats.
Lorenzo
Sherilyn
Elaine Morgan <elaine@NO_SPAM_PLEASE-desco.demon.co.uk> wrote:
...
>
> The strength of the objection (I have frequently pinted out its
> weaknesses) lies in the fact that the fossil remains of other mammals
> are also found (more or less exclusively) in wet places, and some of
> them are the predecessors of species that are clearly not aquatic
> e.g.baboons and giraffes. The danger of the "taxonomic bias"
> argument is that when fossil hunters found hominids with fish and
> turtles and crocodiles they did not think "Aha! water". They had been
> trained to ignore the evidence of water. It got close, as you suggest,
> to the knee-jerk assumption that fossils could "not be associated with
> the location in which they were found "
It is a real problem, I agree. When nature cries wolf like this, it
could be masking real effects that a trained paleoanthropologist will
have to disregard. What one does at that point, I think, is much as
Marc has attempted to do--to try to distinguish the signal from the noise,
Marc points out that a subset of finds (I think he cites "all H. erectus")
are found in one place that's good for fossilization, but not another.
Well that tells us that H. erectus like the sea-side and rivermouths, but
I don't see where it gets us.
Some fossil finds that can be labelled aquatic or semi-aquatic tend to be
unambiguously so, if only because we know that their descendants were or
aquatic (and of course we could make mistakes over this, accepted), but in
the case of human ancestors we have nothing so clear cut, only some traits
that one might argue are close enough to the traits seen in mammals adapted
for life in water. But so much about humans _is_ unique. There's no law
of nature that says things have to turn out a certain way. One might as
well argue that elephants must be descended from insectivores, because
generally insectivores develop a trunk-like proboscis. What is needed is
evidence, not speculation.
In the end, these things are settled either by a build-up of evidence
as with General Relativity, by younger blood coming in and seeing things
from a new perspective, as in the case of the adoption of Darwin's theory
of natural selection by a whole generation of naturalists--sometimes a
combination of both--or simply by a once-popular idea gradually losing
support, as seems to be happening to the Hoyle-Narlikaar Steady State
theory of cosmology.
--
Sherilyn
Sherilyn
"Lorenzo L. Love" <lll...@thegrid.net> wrote:
>
>
> Matt Silberstein wrote:
>
> > In sci.skeptic I read this message from Sherilyn
> > <Sher...@sidaway.demon.co.uk>:
> >
> > >aquatic then it would hurt his sense of symmetry because we would be
> > >members of the only order of animal without an aquatic member (it's not
> > >remotely true, as far as I know).
> >
>
...
> the capybara. And of course like all
> small and medium sized aquatics and semi-aquatics, it has a nice coat of fur.
Well done. But does this support Michael's argument?
PZ Myers
<Sher...@sidaway.demon.co.uk> wrote:
>In article <36031B28...@thegrid.net>,
> "Lorenzo L. Love" <lll...@thegrid.net> wrote:
>>
>>
>> Matt Silberstein wrote:
>>
>> > In sci.skeptic I read this message from Sherilyn
>> > <Sher...@sidaway.demon.co.uk>:
>> >
>> > >What Michael is trying to say here, I think, is that if we are not
>> > >aquatic then it would hurt his sense of symmetry because we would be
>> > >members of the only order of animal without an aquatic member (it's not
>> > >remotely true, as far as I know).
>> >
>> > The aquatic rodent is a wily beast and very shy of man.
>...
>>
>...
>> the capybara. And of course like all
>> small and medium sized aquatics and semi-aquatics, it has a nice coat of fur.
>
>Well done. But does this support Michael's argument?
Of course. You don't know Michael very well if you don't yet realize that
every piece of evidence somehow supports his argument.
--
PZ Myers
John Cason
>>> The aquatic rodent is a wily beast and very shy of man.
> ...
>> the capybara. And of course like all
>> small and medium sized aquatics and semi-aquatics, it has a nice coat of
fur.
> Well done. But does this support Michael's argument?
Don't forget the point about ability to constrict the nose. Aquatic bats
have fur and many species can close their nasal passages. As can camels,
who also have fur. Their ability to vary the water content of their bodies
was originally a way to adjust bouyancy for better bottom-feeding.
Likewise, the large, furry, semi-aquatic North American moose obtains a
substantial part of its diet by eating algal mats on the bottom of shallow
lakes. It should be able to constrict the nasal passages, and subcutaneous
fat would come in handy in that cold water. Not to mention where we find
all the good moose fossils. QED.
This modern biology is lots more fun than the old, plodding biology that
used to be taught in school.
Sherilyn
my...@netaxs.com (PZ Myers) wrote:
> In article <6u0825$b7r$1...@nnrp1.dejanews.com>, Sherilyn
> <Sher...@sidaway.demon.co.uk> wrote:
> >In article <36031B28...@thegrid.net>,
> >> > >aquatic then it would hurt his sense of symmetry because we would be
> >> > >members of the only order of animal without an aquatic member (it's not
> >> > >remotely true, as far as I know).
> >> >
...
> >> the capybara. And of course like all
> >> small and medium sized aquatics and semi-aquatics, it has a nice coat of
> >> fur.
> >
> >Well done. But does this support Michael's argument?
>
> every piece of evidence somehow supports his argument.
Being a self-proclaimed genius scientist and mass murderer isn't easy;
he has to economize with the evidence.
PZ Myers
[snip]
[snip]
Tsk, tsk. We went all over this a year or so ago, Mr. Reynolds.
This whole line of argument, that you can use the orientation of
the legs relative to the spine, as evidence for the aquatic ape
hypothesis is simply silly. It's an extremely superficial analogy
that requires a stubborn refusal to actually look at the limbs of
these animals.
You want to argue that the orientation of the legs is a functional
adaptation that is only seen in swimming animals. You also insist
that it has to be that way, because otherwise humans are the odd
mammal out, and for some reason, that bothers you. Unfortunately,
there is nothing in human pelvic and limb anatomy to suggest any
convergence on the aquatic mammal plan. There is also no logical reason
why one particular species ought not to be allowed to have a unique
evolutionary history.
There are a set of anatomical changes to the limbs of marine mammals
that seem to be reasonable functional adaptations. As you've noted,
hindlimbs tend to be modified to provide propulsive force along the long
axis of the animal, along the axis of movement, rather than perpendicular
to that axis, to provide support against the force of gravity. The fact
that humans also have hindlimbs oriented parallel to the body axis seems
to be the sole comparison you want to make. However, in our case the
pelvis exhibits a number of traits that represent adaptations to allow
the limbs to support us against the pull of gravity, not to propel us
through the water. And the adaptations found in marine mammals may enable
it to swim well, but they certainly aren't the beginnings of a useful
exaptation that would allow one to walk bipedally on land. When was the
last time you saw a seal hop up on its hind flippers and walk around?
Look at the bones of a seal or otter. They have a pelvis that is typical
of other Carnivora, elongate longitudinally and forming a kind of dorsal
plate. The main differences from a 'typical' mammalian pelvis are a trend
towards reduction of the ilium and the absence of a pubic symphysis -- the
whole bone is being minimized. It is no longer needed as an important
brace for supporting the weight of the animal, and isn't even providing
an attachment for powerful muscles needed in locomotion. It is fading
away, and you can see that in the bones.
Now look at a human pelvis...there we see functional adaptations along a
completely different line. Compared to a cat or a chimp, there is a
change in orientation -- it's less of a dorsal plate, and is more compressed
longitudinally. The ilium is broad and wide, and is an important attachment
point for muscles critical in maintaining our posture. The pubis and ischium
are robust and form a strong symphysis. The pelvis is a solid ring of
bone that cradles our guts and links legs to spinal column.
Compare a pinniped and a human, and you can see that they've been going
in completely opposite directions! Our hindlimbs aren't adaptations for
better swimming. They don't exhibit any of the anatomical characteristics
that are common in aquatic mammals, but they do seem to function pretty
well in terrestrial locomotion. I would argue that if we *had* gone partway
down the road to an aquatic lifestyle, that would rather effectively
cripple our ancestors and prevent them from returning to the land. How
successful do you think a seal or a sirenian would be if it decided to
give up on the sea and hunt or graze on the land?
--
PZ Myers
Sherilyn
Myers <my...@netaxs.com> writes
>In article <6tq5n0$sed$1...@nnrp1.dejanews.com>, myke_r...@yahoo.com wrote:
>
>[snip]
>
>>
>>I'd like to see an objective rebuttal of what I think
>>is the most compelling argument for AAT, which is the
>>morphology of pelvic bones in formerly terrestrial
>>aquatic and semi-aquatic marine animals.
>Compare a pinniped and a human, and you can see that they've been going
>in completely opposite directions! Our hindlimbs aren't adaptations for
>better swimming. They don't exhibit any of the anatomical characteristics
>that are common in aquatic mammals, but they do seem to function pretty
>well in terrestrial locomotion. I would argue that if we *had* gone partway
>down the road to an aquatic lifestyle, that would rather effectively
>cripple our ancestors and prevent them from returning to the land. How
>successful do you think a seal or a sirenian would be if it decided to
>give up on the sea and hunt or graze on the land?
>
effectively rebutted Michael's admittedly poor argument. One thing that
now strikes me about the AAT, which I first encountered in '76 in the
form of Elaine Morgan's The Descent of Woman, is that it's rather like
the Face on Mars, a myth that NASA exploded with obvious glee earlier
this year. Both seem to be acting as a proxy for some internal
struggle.
--
Sherilyn
Grad Student, University of Ediacara
Marc Verhaegen
>In article <6tuejk$ke8$1...@xenon.inbe.net>,
> "Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
>>
>> Sherilyn heeft geschreven in bericht <6tpici$7qv$1...@nnrp1.dejanews.com>...
>> ...
>> >acknowledging that the AAT would be a particularly powerful explanation
>> >of some traits (though not of others) I await that evidence. It is
worth
>> >noting that none of the responsible protagonists of the AAT is claiming
>> >that such evidence has been uncovered.
>> >--
>> ???
>> No?
>>
>> All the evidence is there, please open your eyes.
>> If you mean fossil evidence:
>> 1) anatomical evidence: H.erectus, eg, if full of (ex)aquatic features:
>> linear build, ear exostoses, dense bones...
>
>I'm afraid it's simply conjecture at this stage to attribute specific
>traits, as you apparently wish to do, to aquatic adaptation. I agree
>that it would be nice if we could pin it down neatly, but I do think some
>evidence would be required, not just nice neat stories. I do get
>suspicious when people say "B is like C, A caused C, therefore A caused
>B." That isn't evidence, it's speculation.
???
Just to take the examples I used:
a) Linear build is like diving mammals. AFAIK there is no nondiving mammal
with a linear build. And conversely all mammals that can dive well can adopt
a linear build.
b) Among humans, ear exostoses are only seen in people who dive freqeuntly
in cold water.
c) Very dense bones as in H.erectus are only seen in slow bottom-divers
(walruses & seacows).
That's evidence. B is like C. You don't need the A, Sherilyn.
But in many instances the A can easily be explained. The more "easily", the
less speculation.
a) Linear build: obvious, isn't it?
b) Auditory exostose are the complication of chronic external otitis in
people with live-long diving. How this works is speculation, & not needed
for our goal. Perhaps vascular reactions (cold), perhaps chronic skin
irritation or infection, probably the combination.
c) If you want to read a (IMO excellent) speculative explanation, see
M.Roede ed.1991 'The aquatic ape: fact or fiction?" Souvenir London.
>> 2) paleo-environmental evidence: All hominids are found in "wet"
environments,
>
>The _fossils_ are found in wet environments. That's where fossils are
>made, generally. Somebody did recently mention some rare wind-blown
>fossilization in an arid environment that doesn't seem to match your
>above statement (apologies if I misread the posting).
You must have misread. Laetoli: arid environment?? what do colobines do in
arid environments??
Just 3 examples (I you want I send you some more):
- Hadar AL.333 A. afarensis: ‘The bones were found in swale-like features …
it is very likely that they died and partially rotted at or very near this
site … this group of hominids was buried in streamside gallery woodland’
(Radosevich et al., 1992).
- Makapan A. africanus: ‘…very different conditions from those prevailing
today. Higher rainfall, fertile, alkaline soils and moderate relief
supported significant patches of sub-tropical forest and thick bush, rather
than savannah. Taphonomic considerations… suggest that sub-tropical forest
was the hominins’ preferred habitat rather than grassland or bushveld, and
the adaptations of these animals was therefore fitted to a forest habitat’
(Rayner et al., 1993; see also Reed, 1993; and Wood, 1993).
- Olduvai: ‘…the middle Bed-I faunas indicate a very rich closed woodland
environment, richer than any part of the present-day savanna biome in
Africa…' (Fernández-Jalvo et al., 1998).
No fossil hominoid, hominid, australopith or human was ever found in an arid
environment.
- Early australopiths are usu. (always?) found in forested areas, often
gallery forests.
- Robust australopiths are often found in more open areas, though always
near trees & water, ie, the kind of environment were lowland gorillas seek
their 'aquatic herbaceous vegetation'.
- Early Homo is always found near molluscs & lakes. Outside Africa the
earliest erectus are found in rivers & deltas (Mojokerto).
> And once again,
>simply living by the sea shore or near a lake is not evidence of aquatic
>or semi-aquatic adaptation. They'd have to be pretty much up to their
>necks most of the time, and in that case I'd be inclined to ask: where
>are the fossils? I would expect many more than have been found.
>
>>there is no evidence whatsoever for a savanna milieu.
>
>I'm not sure what the above non sequitur is doing in a discussion of
>whether humans were adapted to an aquatic existence. Is this an example
>of a false dichotomy?
I first want to get that stupid savanna image of human evolution out of our
minds.
Once that is settled, we can think with more open minds.
>
>> H.erectus esp. is often found in seacoasts & river deltas, although
inland
>> fossilisation (riverine, lacustrine...) is much more probable. Do you
want
>> me to send my list?
>
>I think you posted it a few times already, but I'm still puzzled. Why do
>you think that a fondness for a seaside and estuary existence in H. erectus
>means his miocene or australopithecine ancestor must have been partially
>adapted for aquatic or semi-aquatic existence?
(Why do you think I think what you're writing here?)
>I accept that he could have been, but the evidence is ambiguous, to put it
mildly.
Yes, the paleo-environmental evidence, no doubt, is not enough.
You have to take all the available evidence, not just the fossil evidence.
(And you do realise that fossils are nearly always sidebranches, not direct
ancestors of living species?)
It's not the paleo-milieu which makes me think that our ancestors often
dived for shellfish, it's the comparative data of our anatomical features,
which are not contradicted by any fossil evidence.
Marc
Marc Verhaegen
Matt Silberstein heeft geschreven in bericht
...
>Ok, so what is your point? Are you claiming that the elephant is an
>(semi-) aquatic animal? If so, you seem to have redefined the term.
>>
I'm saying that elephants have been seen using the proboscis as a snorkel.
(But I have no doubt that elephants are ex-semi-aquatic, if you like such
terms. Forest elephants spend a lot of time in water, savanna elephants do
this whenever they can, Indian elephants are between. Other pachyderms like
hippos & all 3 Asian rhino species are still semi-aquatic.)
>[unmarked snip here]
>>
>>>>Yes, furlessness is not enough as explanation, although 95% of furless
>>species are fully or strongly aquatic.
>>>
>>>References please?
>>
>>In 1985 (Med.Hypoth.16:17) I counted all the furless mammalian species
(95%)
>>and genera (90%). Easy to verify. The furless "terrestrials" were, AFAIR,
2
>>elephant species, 2 rhino species, naked bat, naked mole rat.
>>
>So the hippo counts as aquatic, but the elephant does not.
>
Yes.
...
...
> It seems to me that some aquatic
>mammals are furred and some furless. Some non-aquatic mammals are
>furred and some furless. So the fur does not mean much either way.
>
>>As for the medium-sized mammals, all non-tropical semi-aquatics are
furred.
>>The explanation seems to be simple: they need the fur for thermoregulation
>>on land. All pinnipeds have fur, except the very big adult male Steller
>>sealions, walruses & elephant seals.
>>
>So this does not do much for your argument, does it?
>
Why not? It depends on what you mean by "much". Of course nobody says
furlessness alone proves the AAT. So what is your point?
Marc
Marc Verhaegen
>In article <6tuh9r$mur$1...@xenon.inbe.net>,
> "Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
>>
>> Sherilyn heeft geschreven in bericht <6trodj$l46$1...@nnrp1.dejanews.com>...
>>
>> >>1) If human beings are not semi-aquatic, then primate is the only order
>> >>of mammal without an aquatic member.
>> >>
>> Exaggeration.
>
>>
>> >I do not believe I have seen Michael advance an explanation of the
>> >adaptation of sweating for cooling in humans. Why would an aquatic
>> >animal need to cool down?
>> >
>> For cooling down on land.
>
glands.
I believe, eccrine sweat glands are present in apes, but much less than in
humans.
Do monkeys have many eccrines?
> If modern humans need more sweat glands (we do, after all, have
>radically different lifestyles than most apes, and we don't know how
>recent the widespread sweat glands are) then an aquatic phase would be
>superfluous.
If that were the only thing we knew, yes.
But we know more. See the furseals on land that profusely sweat
thermoregulatorily through eccrine sweat glands.
>>
>> >The nose can be used as a form of signal, making human faces almost
>> >uniquely expressive in the animal kingdom. Perhaps this is evidence
>> >that signalling started early in humans, even before the development of
>> >proper speech.
>> >
>> Sherilyn, such "unique" explanations are anthropocentric & therefore IMO
not
>> allowed.
>> We have to use the comparative evidence. The most humanlike nose is seen
in
>> proboscis monkeys. Other mammals with external noses are: elephants,
tapirs,
>> suids, sea elephants, hooded seals.
>
>I strongly disagree with your suggestion.
No, Sherilyn, after all, that's all we really have: the comparative
evidence. All the rest easily become speculation.
(Or do you disagree that proboscis monkyes, elephants, tapirs, sea
elephants, hooded seals have external noses?)
>The only _evidence_ that would
>really be acceptable here would be that which can rule out one or other
just-so story.
Yes, that's the comparative evidence.
>You don't like mine, I'm not so sure about Michael's.
>They have one thing in common: nobody knows the truth.
We do know something about the truth. Try to rule out the following story.
(It's not a just-so story. Every detail of this story is based upon
comparative evidence.)
DID CHIMP AND GORILLA FOREBEARS WALK ON TWO LEGS?
Most primates are arboreal quadrupeds with mobile joints and limbs that can
be straightened to reach other branches. This locomotor flexibility allows
them to adopt a bipedal gait with extended knees and hips when wading
through shallow water (and not the leaping bipedality that some primates use
when moving on the ground). For example, proboscis monkeys Nasalis larvatus
cross stretches of water to reach other mangrove trees walking on two legs,
and lowland gorillas G. g. gorilla go wading on their hindlimbs through
forest swamps to supplement their diet with swamp herbs and sedges (see
below AHV). In the same way, we suggest the earliest hominids might have
been bipeds part of the time, wading in tidally or seasonally flooded
forests.
According to the molecular data, the pongids (Pongo) and the hominids
(Gorilla, Pan, Homo) broke into two groups some 10 Myr BP. Then the
forebears of the gorillas and those of humans and chimps split apart about 8
or 6 Myr BP. Most recently the ancestors of the chimpanzees and those of
humans separated between 6 and 4 Myr BP (e.g. Kumar & Hedges, 1998). Of the
living hominoids, the hylobatids (gibbons and siamangs) and the pongids
(orang-utans) live in Asia, whereas only the hominids (humans, chimpanzees
and gorillas) live in Africa. About 10 Myr BP, most hominoids, such as
dryopithecines, sivapithecines and ouranopithecines, are found in Eurasia
(Cameron, 1997). Ankarapithecus meteai, for instance, which displays
features of both pongids and hominids, has been discovered in Anatolia
(Algaput et al., 1996). These data suggest that pongids and hominids split
somewhere in Eurasia, possibly in the Near East. Therefore it seems likely
that a basic hominid population, perhaps 10 or 8 Myr BP, before entering
Africa, clustered in the mangrove forests between Asia and Africa in what
eventually became the Red Sea.
These bipedally wading hominids might have fed partly on the oysters fixed
to the mangrove trunks exposed at low tide. This high-caloric and highly
nutritious diet could have facilitated the building and fuelling of a large
brain. The long-chain poly-unsaturated lipid ratios of tropical fish and
shellfish are more similar to those in the human brain than all other food
sources known (Broadhurst et al., 1998). But shellfish, just as fish and
meat and most animal foods, lack vitamin C. Most higher primates are
predominantly frugivores that cannot produce their own vitamin C. Fruit
production occurs mostly in forested areas but is often seasonal. Therefore,
shellfish is a welcome dietary supplement for a dextrous frugivore in
mangrove forests. This is illustrated by the oyster-eating capuchin monkeys
of the mangrove areas (Fernandes, 1991).
Tool use is seen in diverse animals, but the best examples among mammals are
the capuchin monkeys, the chimpanzees and the sea otters. They all try to
open hard-shelled foods by hammering with hard objects. Sea otters Enhydra
lutris feed on shellfish and crack the shells with stones. Mangrove
capuchins Cebus apella apella even use oyster shells where stones are not
available (Fernandes, 1991). Chimpanzees and capuchins also crack open nuts
with stones. It thus seems likely that stone tool use often began with
shellfish or nut eating. No doubt, the hominids, like the capuchins and the
sea otters, manipulated hard objects for opening nuts and oysters. Arguably,
this was the beginning of the human Stone Age technology.
Presumably the earliest hominids had thick enamel (Martin, 1985), like most
earlier and later relatives, for instance, Siva-, Ourano- and Ankarapithecus
(e.g. Cameron, 1997; Algaput et al., 1996) and the australopithecines
(without ramidus, see White et al., 1994; Andrews, 1995). Developmental
mechanisms to account for the thick and thin enamel in hominoids have been
proposed by Martin (1983, 1985). Thick enamel is typical of capuchin monkeys
or sea otters that eat hard-shelled foods like nuts or molluscs (Fernandes,
1991; Walker, 1981). In the sea otters, it is perhaps not for cracking the
shells, but for the occasional hard inclusions, which could otherwise damage
the dentition (Walker, 1981).
Homo erectus-like people colonised the Indian Ocean shores, and even reached
as far as Java perhaps as early as 2 Myr BP. Over time, these omnivores
improved their shellfish collection and preparation techniques. Stone use
and tool manipulation proceeded as a means of extracting the meat. It is
likely that this advanced their swimming and even their diving adaptations.
Diving is still practised by diverse human populations that collect
shellfish through breath-hold diving, and diving capabilities are obvious in
the human physiology as opposed to nonhuman primates (Schagatay, 1996). All
diving mammals have the ability to breathe at free will whenever they intend
to dive. Many of them, like dolphins and seals, also have large brains. We
think that large brains and voluntary breathing, in combination with the
rich vocal and musical abilities as seen in primates like gibbons and other
arboreal animals (Darwin, 1871), were prerequisites for what we now call
human language.
Dextrous hands and large brains and spoken language then predisposed them to
occupy also the inland milieus along the rivers. Our ancestors’ linear
build - with the extended knees and hips and lumbar lordosis suited for
wading and swimming and diving - made it too difficult for them to re-adopt
quadrupedal gait. At first they might have spent much of their time wading
and fishing in rivers and lakes. Acheulian populations in Africa are
described as stenotopic, occupying a narrow niche in riverine-wetland
habitats, whereas only in the Middle and Late Stone Ages human populations
became eurytopic, occupying the same niche as the traditional foragers in
Africa today (Deacon, 1998).
Thus in the last two million years, different Homo populations became, to
different degrees, long-legged bipeds. These lines probably included
rudolfensis and ergaster in Africa, erectus and neanderthalensis in Eurasia,
and finally sapiens.
Algaput B., Andrews P., Fortelius M., Kappelman J., Temizsoy I., ?elebi H.
and Lindsay W., 1996. A new specimen of Ankarapithecus meteai from the Sinap
Formation of central Anatolia. Nature, 382: 349-351.
Andrews P., 1995. Ecological apes and ancestors. Nature, 376: 555-556.
Broadhurst C. L., Cunnane S. C. and Crawford M. A., 1998. Rift Valley fish
and shellfish provided brain-specific nutrition for early Homo. British
Journal of Nutrition, 79: 3-21.
Cameron D. W., 1997. A revised systematic scheme for the Eurasian Miocene
fossil Hominidae. Journal of Human Evolution, 33: 449-477.
Chadwik D., 1995. Ndoki – last place on earth. National Geographic, 188:
2-43.
Darwin C., 1871. The Descent of Man. London: John Murray.
Deacon H. J., 1998. Modern human emergence: an African archaeological
perspective. In (M. A. Raath, H. Soodyall, D. Barkhan, K. L. Kuykendall and
P. V. Tobias eds) Abstracts of Contributions to the Dual Congress 1998, p.
35, Johannesburg: Witwatersrand University.
Doran D. M. and McNeilage A., 1997. Gorilla ecology and behavior.
Evolutionary Anthropology, 6: 120-130.
DuBrul E. L., 1977. Early hominid feeding mechanisms. American Journal of
Physical Anthropology, 47: 305-320.
Edelstein S. J., 1987. An alternative paradigm for hominoid evolution. Human
Evolution, 2: 169-174.
Fernandes M. E. B., 1991. Tool use and predation of oysters by the tufted
capuchin in brackish water mangrove swamp. Primates, 32: 529-531.
Kleindienst M. R., 1975.On new perspectives on ape and human evolution.
Current Anthropology, 16: 644-646.
Kumar S. and Hedges S. B., 1998. A molecular timescale for vertebrate
evolution. Nature, 392: 917-920.
Martin L. B., 1983. The Relationships of the Later Miocene Hominoidea. PhD
thesis, University of London.
Martin L. B., 1985. Significance of enamel thickness in hominoid evolution.
Nature, 314: 260-263.
Nelson G., 1998. Colin Paterson (1933-1998). Nature, 394: 626.
Puech P.-F., 1992. Microwear studies of early African hominid teeth.
Scanning Microscopy, 6: 1083-1088.
Puech P.-F., Albertini H. and Masali M., 1984. L’orang-utan e l’origine dell
’uomo. Antropologia Contemporanea, 7: 301-308.
Puech P.-F., Cianfarani F. and Albertini H., 1986. Dental microwear studies
as an indicator for plant food in early hominids. Human Evolution 1:
507-515.
Radosevich S. C., Retallack G. J. and Taieb M., 1992. Reassessment of the
paleoenvironment and preservation of hominid fossils from Hadar, Ethiopia.
American Journal of Physical Anthropology, 87: 15-27.
Rayner R. J., Moon B. P. and Masters J. C., 1993. The Makapansgat
australopithecine environment. Journal of Human Evolution, 24: 219-231.
Schagatay E., 1996. The human diving response – effects of temperature and
training. Lund, Sweden: University of Lund.
Walker A., 1981. Diet and teeth – dietary hypotheses and human evolution.
Philosophical Transactions of the Royal Society of London B, 292: 57-64.
White T. D., Suwa G. and Asfaw B., 1994. Australopithecus ramidus, a new
species of early hominid from Aramis, Ethiopia. Nature, 371: 306-312..
>> >
>> >>9) Hair loss is most often associated with aquatic adaptation. While
>> >>some semi-aqautic mammals retain fur (no fully aquatic mammals do),
>> >>there are vanishingly few examples of non-aquatic mammals loosing their
>> >>fur. Rhinos and hairless moles are the only counter examples I can
>> >>think of.
>> >
>> >Hair loss? Check your skin, Michael. I checked mine and yes, I am
>> >covered all over in fine hairs. Sexual selection can account for this.
>
>I should of course have said "could". It's a devil's advocate position.
>
>> >
>> No, Sherilyn, no "unique" explanations please. If sexual selection
accounted
>> for that, cats & zebras should be furless too.
>
>And peacock's tails cannot possibly be due to sexual selection, otherwise
>all male birds would have enormous tails.
>
>http://www.sidaway.demon.co.uk/skeptic/toolkit.html
>
>Nice troll, Marc. You had me going, there.
>--
Yes, I exaggerated. But the peacock is not alone in having long & coloured
feathers, just see the paradise birds. Besides, female peacocks (peahens?)
does not have an enrmous tail. Or are you saying that male Steller sealions
are furless because the females like them like that, and the females are
furred because the males like it like that?
If sex.selection accounted for our furlessness, why do both human sexes
incl. children lack fur?
Marc
Marc Verhaegen
all
>small and medium sized aquatics and semi-aquatics, it has a nice coat of
>then there are other aquatic rodents like musk rats, beavers and nutrias,
all
>well known for their thick fur coats.
>
1) Ever seen a furless "early hominine"?
2) Capybaras (25-80kg) spend a lot of time (most?) feeding on land, near
rivers etc. & flee into the water when disturbed. AFAIR, the larger
capybaras have no nice coat of fur & lack underfur.
3) Smaller semi-aquatics of course have fur.
4) All semi-aquatics in temperate climates have fur, of course.
Marc Verhaegen
PZ Myers heeft geschreven in bericht ...
...
>Compare a pinniped and a human, and you can see that they've been going
>in completely opposite directions!
???
Just see the foot skeleton of a furseal & of a human.
>Our hindlimbs aren't adaptations for better swimming.
>They don't exhibit any of the anatomical characteristics
>that are common in aquatic mammals,
From my 1993 paper "Aquatic vs savanna..." Nutrition & Health 9:165-191:
Elongated foot, subequal toe length, broad end phalanges
The human foot is clearly different from that of most apes and monkeys
(whose feet look rather like hands) and certainly from that of savanna
mammals (which run on their toes or hooves): its broad distal phalanges,
subequal toe length, nearly parallel digital rays, and flat and elongated
foot largely covered by a common integument are found in semi-aquatics as
different as water opossums (Böker, 1935, 188) and eared seals (Figure l).
The convergent evolution of the sealion's and the human foot as opposed to
the chimpanzee's is striking, although the evolutionary distance between man
and chimp (c.6 million years) is at least ten times less than that between
pinnipeds and hominoids.
Paleontologists who find fossil hominid footbones or footprints seem to
assume that only bipedal mammals evolve feet of this shape and that all
bipedal mammals evolve such feet. But the only animal that walks bipedally
on the African savanna (and that can also run very efficiently and fast) is
the ostrich, but its foot is higher and shorter than the human foot and has
only two toes, which are spread widely apart and are unequal in length. The
bipedally leaping kangaroo has very elongated, but also very narrow feet;
the second and third (syndactylous) and the fifth digital rays are much
weaker and shorter than the (central) fourth ray and diverge from it. The
statement that every bipedally striding mammal develops humanlike feet is
statistically invalid, since there is only one mammal that walks like
humans. In fact, the ape with feet that most resemble the human is the
highland gorilla (Schultz, 1934, 58), the slowest and most quadrupedal of
the apes. All African apes, however, resemble humans in being plantigrade,
not only in terrestrial, but also in arboreal locomotion, while the other
primates (including the orang) have their heels elevated (semi-plantigrady)
when moving in the trees and even on the ground (Gebo, 1992).
Very long legs
One of the first arguments used against the aquatic theory was that when a
mammal becomes aquatic, the limbs - and especially the lower limbs - become
shorter, whereas humans have very long legs and, to a lesser extent, long
arms in relation to trunk length. Long limbs are seen in many savanna and
many arboreal mammals. Very long legs (which in rest are usually flexed,
however) are far more typical of arboreal (vertical leapers: indri, tarsier)
than of savanna mammals (kangaroo).
Although the human leg length is much more typical of terrestrial than of
aquatic mammals, there is both fossil and ontological evidence that part of
this lengthening was a very late development. (1) All fossil hominids had
legs relatively shorter than ours; even the Neandertals still had shin bones
shorter than the human. (2) "At birth man possesses remarkably short limbs",
but soon thereafter the human legs - and to a lesser degree the arms -
become relatively longer (Schultz, 1936, 433). The recent hind limb
lengthening could have been advantageous for wading in shallow water (heron,
flamingo) as well as for walking on land.
Stretched angle between bind limbs and spine
Humans habitually stand and walk with the angle between trunk and leg
approaching 180° - a feature equally characteristic of many swimming and
diving mammals, but absent in terrestrial ones. Many arboreal mammals have a
tendency for truncal erectness (e.g., vertical clingers and leapers,
brachiators): gibbons walking bipedally along branches have only slightly
bent hips and knees and rather large lumbo-sacral angles. Some savanna
mammals adopt a bipedal posture for special purposes: meerkats and vervets
stand erect to keep watch, and gerenuk antelopes to eat acacia and mimosa
leaves. But in no case did this behaviour evolve into erect bipedal
locomotion. Savanna-bound explanations of bipedality (e.g., Jolly, 1970;
Lovejoy, 1981; Sinclair et al., 1986) are easily refuted (e.g., Conroy,
1990, 347-351;Verhaegen 1987a, 1991b). The aquatic theory also has
difficulty in explaining bipedality: only a few semi-aquatic mammals show
tendencies to bipedalism (Morgan, 1982, 58-63). So it must be the
combination of an arboreal and an aquatic past that accounts for human
bipedality.
Marc
Marc Verhaegen
Sherilyn heeft geschreven in bericht <6tv4jr$ar1$1...@nnrp1.dejanews.com>...
[I +- agree on the snipped]
>
>Some fossil finds that can be labelled aquatic or semi-aquatic tend to be
>unambiguously so, if only because we know that their descendants were or
>aquatic (and of course we could make mistakes over this, accepted), but in
>the case of human ancestors we have nothing so clear cut, only some traits
>that one might argue are close enough to the traits seen in mammals adapted
>for life in water. But so much about humans _is_ unique.
I think, if we analyse human "unique" features in detail, there is not so
much that is completely unique.
(Of course the combination of our features is very unique. No doubt humans
are very special primates, and there must have been some "irregular"
evolutionary history.)
>There's no law of nature that says things have to turn out a certain way.
If you are a mammal & you're adapting to aquatic life, at some point, you
will loose your fur, because all fully aquatics are furless. So we can say:
if you are fully aquatic, you "must" have lost your fur.
>One might as well argue that elephants must be descended from insectivores,
because
>generally insectivores develop a trunk-like proboscis.
Well, it certainly would be an argument. But the difference is that in
insectivores the mouth is almost at the top of the "trunk-like proboscis".
This is not the case in elephants, tapirs, hooded seals, elephant seals.
Marc
Sherilyn
"Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
> Sherilyn heeft geschreven in bericht <6tv096$6ec$1...@nnrp1.dejanews.com>...
> >In article <6tuh9r$mur$1...@xenon.inbe.net>,
> > "Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
> >>
> >> Sherilyn heeft geschreven in bericht <6trodj$l46$1...@nnrp1.dejanews.com>...
> >> >I do not believe I have seen Michael advance an explanation of the
> >> >adaptation of sweating for cooling in humans. Why would an aquatic
> >> >animal need to cool down?
> >> >
> >> For cooling down on land.
> >
> >Reasonable, though this is conjecture, and other primates do have sweat
> glands.
>
> I believe, eccrine sweat glands are present in apes, but much less than in
> humans.
> Do monkeys have many eccrines?
I don't know. If you want to argue that _all_ apes are aquatically adapted,
I guess if you find absence of apocrine glands in monkeys, that might be
useful.
>
> > If modern humans need more sweat glands (we do, after all, have
> >radically different lifestyles than most apes, and we don't know how
> >recent the widespread sweat glands are) then an aquatic phase would be
> >superfluous.
>
> If that were the only thing we knew, yes.
> But we know more. See the furseals on land that profusely sweat
> thermoregulatorily through eccrine sweat glands.
So a requirement for cooling in mammals can be fulfilled by an
adaptation for more eccrine sweat glands, which are already present
in apes. Yes, I got that far.
>
> >>
> >> >The nose can be used as a form of signal, making human faces almost
> >> >uniquely expressive in the animal kingdom. Perhaps this is evidence
> >> >that signalling started early in humans, even before the development of
> >> >proper speech.
> >> >
> >> Sherilyn, such "unique" explanations are anthropocentric & therefore IMO
> not
> >> allowed.
> >> We have to use the comparative evidence. The most humanlike nose is seen
> in
> >> proboscis monkeys. Other mammals with external noses are: elephants,
> tapirs,
> >> suids, sea elephants, hooded seals.
> >
> >I strongly disagree with your suggestion.
>
> No, Sherilyn, after all, that's all we really have: the comparative
> evidence. All the rest easily become speculation.
That's what you're doing, don't you see? You see two animals with
similar (not very similar, in many cases) adaptations, and you _assume_
that they are due to the same cause. Then you call the similarity
"comparative evidence."
> (Or do you disagree that proboscis monkyes, elephants, tapirs, sea
> elephants, hooded seals have external noses?)
Looks like a non sequitur. Are you trolling me as you did over
sexual selection?
>
> >The only _evidence_ that would
> >really be acceptable here would be that which can rule out one or other
> just-so story.
>
> Yes, that's the comparative evidence.
No, at this point I really think you are probably trolling for fun, to see
how much bad logic I will swallow. Your assertion of a link between similar
characteristics certainly cannot be used to rule out your "just-so" story
or any other. I don't think further dialog of this nature will help either
of us.
...
PZ Myers
<Marc.Ve...@village.uunet.be> wrote:
>Matt Silberstein heeft geschreven in bericht
><360bdfde...@nntp.ix.netcom.com>...
>
>...
>>Ok, so what is your point? Are you claiming that the elephant is an
>>(semi-) aquatic animal? If so, you seem to have redefined the term.
>>>
>I'm saying that elephants have been seen using the proboscis as a snorkel.
>
>(But I have no doubt that elephants are ex-semi-aquatic, if you like such
>terms. Forest elephants spend a lot of time in water, savanna elephants do
>this whenever they can, Indian elephants are between. Other pachyderms like
>hippos & all 3 Asian rhino species are still semi-aquatic.)
>
[snip]
Have you ever heard of Darwin's story for the evolution of whales? He
suggested that they could have evolved from swimming bears snapping at
flies, based on a few flimsy anecdotes. He later came to be rightly
embarassed by it. Creationists still sometimes trot it out as a good
example of evolutionist absurdity.
Your 'elephant trunk as a snorkel' idea is just as silly. Your whole
abuse of the concept of "semi-aquatic" has watered down the idea so
much that it is worthless. Yes, rhinos and elephants like to play and
bathe and cool off in the water. I wouldn't be at all surprised if
early hominids did likewise, although I'm not sure how you would provide
evidence for such a thing. However, the question is whether these animals
experienced such a prolonged reliance on aquatic life that it has significantly
shaped their anatomy -- and anecdotes about elephants frolicing in the
water hole are not convincing.
--
PZ Myers
PZ Myers
<Marc.Ve...@village.uunet.be> wrote:
Oh, please...you can't tell the difference between a human foot and a
seal's flipper? Both have long phalanges, but for obviously different
reasons -- the seal is increasing surface area for more effective locomotion,
the human is building an arched support to bear his weight.
The claim that "every bipedally striding mammal develops humanlike feet"
is a strawman. I've never heard *anyone* suggest such a thing, other than
yourself. Similarly, the idea that aquatic or semi-aquatic mammals
evolve human-like feet is also a unique absurdity that I've only heard from
you. You've also suggested that elephants evolved from an aquatic ancestor--
are you going to suggest that they have human-like feet, too?
>
>Very long legs
>
>One of the first arguments used against the aquatic theory was that when a
>mammal becomes aquatic, the limbs - and especially the lower limbs - become
>shorter, whereas humans have very long legs and, to a lesser extent, long
>arms in relation to trunk length. Long limbs are seen in many savanna and
>many arboreal mammals. Very long legs (which in rest are usually flexed,
>however) are far more typical of arboreal (vertical leapers: indri, tarsier)
>than of savanna mammals (kangaroo).
>Although the human leg length is much more typical of terrestrial than of
>aquatic mammals, there is both fossil and ontological evidence that part of
>this lengthening was a very late development. (1) All fossil hominids had
>legs relatively shorter than ours; even the Neandertals still had shin bones
>shorter than the human. (2) "At birth man possesses remarkably short limbs",
>but soon thereafter the human legs - and to a lesser degree the arms -
>become relatively longer (Schultz, 1936, 433). The recent hind limb
>lengthening could have been advantageous for wading in shallow water (heron,
>flamingo) as well as for walking on land.
Yes, we have longer legs than our distant ancestors. That does not mean you
can imply that if we looked even farther back, we'd see still shorter legs
that converge on the pattern we see in true aquatic mammals. This is a very
misleading suggestion. In *none* of the fossil hominids seen so far is there
any evidence of the kind of short, robust hindlimbs seen in aquatic mammals.
And now you want to argue that our ancestors were flamingo-like waders
rather than divers? Get your story straight, please.
>
>Stretched angle between bind limbs and spine
>
>Humans habitually stand and walk with the angle between trunk and leg
>approaching 180° - a feature equally characteristic of many swimming and
>diving mammals, but absent in terrestrial ones. Many arboreal mammals have a
>tendency for truncal erectness (e.g., vertical clingers and leapers,
>brachiators): gibbons walking bipedally along branches have only slightly
>bent hips and knees and rather large lumbo-sacral angles. Some savanna
>mammals adopt a bipedal posture for special purposes: meerkats and vervets
>stand erect to keep watch, and gerenuk antelopes to eat acacia and mimosa
>leaves. But in no case did this behaviour evolve into erect bipedal
>locomotion. Savanna-bound explanations of bipedality (e.g., Jolly, 1970;
>Lovejoy, 1981; Sinclair et al., 1986) are easily refuted (e.g., Conroy,
>1990, 347-351;Verhaegen 1987a, 1991b). The aquatic theory also has
>difficulty in explaining bipedality: only a few semi-aquatic mammals show
>tendencies to bipedalism (Morgan, 1982, 58-63). So it must be the
>combination of an arboreal and an aquatic past that accounts for human
>bipedality.
And I thought only Michael Reynolds was dim enough to seriously advance
this '180° leg/trunk angle' idea...
I have no idea why our ancestors evolved to spend all their time teetering
about on just two legs. I have no commitment to a savannah theory or any
other idea (although I would tend to argue that at least the initial steps
were not necessarily adaptive at all). However, I do object to the deeply
flawed logic behind extracting one parameter (trunk/leg angle, or phalangeal
length) and using that as a basis for comparison between two kinds of
organisms, while ignoring all the underlying and more substantial
differences (pelvic anatomy, in particular, or the shape and organization of
the hind foot) that suggest that this is not a case of convergent
evolution at all!
--
PZ Myers
PZ Myers
<Marc.Ve...@village.uunet.be> wrote:
>>One of the few semi-aquatic animals in the same weight range as the early
>>hominines is the largest living rodent, the capybara. And of course like
>all
>>small and medium sized aquatics and semi-aquatics, it has a nice coat of
>fur. And
>>then there are other aquatic rodents like musk rats, beavers and nutrias,
>all
>>well known for their thick fur coats.
>>
>Hurray, the first +-sensible thing of LLL.
>
>1) Ever seen a furless "early hominine"?
Nope. Ever seen a hairy one?
You do know that the things like hairiness, skin color, etc. that you
see in hominid reconstructions are all a matter of guesswork, not
evidence, don't you?
>2) Capybaras (25-80kg) spend a lot of time (most?) feeding on land, near
>rivers etc. & flee into the water when disturbed. AFAIR, the larger
>capybaras have no nice coat of fur & lack underfur.
>3) Smaller semi-aquatics of course have fur.
>4) All semi-aquatics in temperate climates have fur, of course.
--
PZ Myers
Lorenzo L. Love
Marc Verhaegen wrote:
> >One of the few semi-aquatic animals in the same weight range as the early
> >hominines is the largest living rodent, the capybara. And of course like
> all
> >small and medium sized aquatics and semi-aquatics, it has a nice coat of
> fur. And
> >then there are other aquatic rodents like musk rats, beavers and nutrias,
> all
> >well known for their thick fur coats.
> >
> Hurray, the first +-sensible thing of LLL.
>
> 1) Ever seen a furless "early hominine"?
> 2) Capybaras (25-80kg) spend a lot of time (most?) feeding on land, near
> rivers etc. & flee into the water when disturbed. AFAIR, the larger
> capybaras have no nice coat of fur & lack underfur.
> 3) Smaller semi-aquatics of course have fur.
> 4) All semi-aquatics in temperate climates have fur, of course.
More lies and distortions. They do not reach 80 kg, they all have full coats
of coarse fur, and live in a tropical climate. This is from Grolier
Encyclopedia which all I have at hand: "The capybara, Hydrochoerus
hydrochaeris, the world's largest rodent, lives in South America and Panama.
It is the only species in its genus, which belongs to the family
Hydrochoeridae, order Rodentia. The capybara--also called carpincho and water
hog--has a massive body, a large head with a blunt snout, short legs, and a
very small tail. It may weigh as much as 50 kg (110 lb) and have a shoulder
height of 50 cm (20 in) and a body length of 130 cm (51 in). Its hair is
coarse, reddish brown above and yellowish below. The feet of the capybara are
webbed and armed with strong claws. Capybaras eat only plants. They are fast
runners and swim well, even under water."
More info at:
http://www.rebsig.com/capybara/
Lorenzo
Sherilyn
<lll...@thegrid.net> writes
>
>
>Marc Verhaegen wrote:
...
>> >
>> Hurray, the first +-sensible thing of LLL.
>
>More lies and distortions.
Have you guys been taking lessons from Michael?
The AAT certainly seems to attract a lot of kooky behavior.
Shaun Denney
>In article <6u2b25$s8v$1...@xenon.inbe.net>, "Marc Verhaegen"
><Marc.Ve...@village.uunet.be> wrote:
>>Matt Silberstein heeft geschreven in bericht
>><360bdfde...@nntp.ix.netcom.com>...
>>...
>>>Ok, so what is your point? Are you claiming that the elephant is an
>>>(semi-) aquatic animal? If so, you seem to have redefined the term.
>>I'm saying that elephants have been seen using the proboscis as a snorkel.
>>(But I have no doubt that elephants are ex-semi-aquatic, if you like such
>>terms. Forest elephants spend a lot of time in water, savanna elephants do
>>this whenever they can, Indian elephants are between. Other pachyderms like
>>hippos & all 3 Asian rhino species are still semi-aquatic.)
I was under the impression that they aren't particiularly closely
related to elephants - I could be mistaken though...
>[snip]
<snip>
>Your 'elephant trunk as a snorkel' idea is just as silly.
Silly perhaps, but true. Indian elephants in some areas swim short
distances to offshore islands on a regular basis, and do indeed hold
their trunks above the surface to breathe, rather than attempting to
lift their entire head clear of the water - can't remember any more
detail, but I've certainly seen film of this.
>Your whole
>abuse of the concept of "semi-aquatic" has watered down the idea so
>much that it is worthless. Yes, rhinos and elephants like to play and
>bathe and cool off in the water. I wouldn't be at all surprised if
>early hominids did likewise, although I'm not sure how you would provide
>evidence for such a thing. However, the question is whether these animals
>experienced such a prolonged reliance on aquatic life that it has significantly
>shaped their anatomy -- and anecdotes about elephants frolicing in the
>water hole are not convincing.
This, however, I agree with entirely. An isolated instance of
elephants swimming does not make them semi-aquatic.
>PZ Myers
Shaun Denney
a.a.#136
============================
My views, not my employers'
============================
Dan Barnes
says...
>
>
>myke_r...@yahoo.com heeft geschreven in bericht
><6tq5n0$sed$1...@nnrp1.dejanews.com>...
>>Sherilyn <Sher...@sidaway.demon.co.uk> wrote:
>>
>>Lucy was definitively fully bipedal. You attempted to argue that
>>she was not as efficient at locomotion, which is irrelevant to
>>the fact that she was definitively fully bipedal.
>>
>"arboreal" adaptations, eg, curved phalanges, toeing-in of feet, small
>femoral heads, mobile knee & ankle joints, low lumbosacral angle...
>
Anatomy Dept here. It has now been published and shows that Lucy walked in a
fully erect bipedal fashion (in "our" sense). See:
Crompton, R.H., Yu, L., Weije, W., Günther, M. & Savage, R. (1998) The
mechanical effectiveness of erect and “bent-hip, bent-knee” bipedal walking in
Australopithecus afarensis. Journal of Human Evolution. 35 (1). 55 - 74.
The retention of some arboreal adaptations doesn't mean Australopithecines
weren't also bipedal but I'm not sure how they fit into an adaptation to an aquatic
environment (it does show that they hadn't yet emerged fully into a savannah
environment either - unlike H.e.).
Dan
PS - anyone know why this is being crossposted to alt.alien.visitors? Is this the
next step for AAT - that our ancestors evolved on a water planet in another solar
system!
Sherilyn
D.Ba...@liverpool.ac.uk (Dan Barnes) wrote:
> In article <6tueuv$kte$1...@xenon.inbe.net>, Marc.Ve...@village.uunet.be
> says...
> >
> >
> >myke_r...@yahoo.com heeft geschreven in bericht
> ><6tq5n0$sed$1...@nnrp1.dejanews.com>...
> >>Sherilyn <Sher...@sidaway.demon.co.uk> wrote:
I did not write anything quoted in this message. Please watch
your attributions.
[Michael reynolds wrote the following:]
> >>Lucy was definitively fully bipedal. You attempted to argue that
> >>she was not as efficient at locomotion, which is irrelevant to
> >>the fact that she was definitively fully bipedal.
> >>
[Marc Verhaegen]
> >Lucy certainly was not bipedal in "our" sense. He/she/it had a lot of
> >"arboreal" adaptations, eg, curved phalanges, toeing-in of feet, small
> >femoral heads, mobile knee & ankle joints, low lumbosacral angle...
> >
[Dan]
> A while ago I mentioned a computer simulation of Lucy done by the Human
> Anatomy Dept here. It has now been published and shows that Lucy walked in a
> fully erect bipedal fashion (in "our" sense). See:
>
> Crompton, R.H., Yu, L., Weije, W., Günther, M. & Savage, R. (1998) The
> mechanical effectiveness of erect and “bent-hip, bent-knee” bipedal walking in
> Australopithecus afarensis. Journal of Human Evolution. 35 (1). 55 - 74.
>
> The retention of some arboreal adaptations doesn't mean Australopithecines
> weren't also bipedal but I'm not sure how they fit into an adaptation to an
> aquatic environment (it does show that they hadn't yet emerged fully into a
> savannah environment either - unlike H.e.).
Philip Deitiker
wrote:
>PS - anyone know why this is being crossposted to alt.alien.visitors? Is this the
>next step for AAT - that our ancestors evolved on a water planet in another solar
>system!
No, because most of the AAT proponents get their ideas from staring
for extended period a large, proximal, celestial electromagnetic
energy producing objects, which has unfortunate consequences on thier
vision, they are probably confusing such objects with UFO and this
explains aav link.
Philip
<pdeitik at bcm.tmc.edu>
Lorenzo L. Love
Dan Barnes wrote:
> PS - anyone know why this is being crossposted to alt.alien.visitors? Is this the
> next step for AAT - that our ancestors evolved on a water planet in another solar
> system!
Isn't that what Reynolds is pushing? And given the improbability of aquatic apes,
wouldn't alien intervention be required to make it happen?
Lorenzo
Marc Verhaegen
Dan Barnes heeft geschreven in bericht ...
>>>
>>Lucy certainly was not bipedal in "our" sense. He/she/it had a lot of
>>"arboreal" adaptations, eg, curved phalanges, toeing-in of feet, small
>>femoral heads, mobile knee & ankle joints, low lumbosacral angle...
>>
>Anatomy Dept here. It has now been published and shows that Lucy walked in
a
Weije, W., Günther, M. & Savage, R. (1998) The mechanical effectiveness of
erect and “bent-hip, bent-knee” bipedal walking in
>Australopithecus afarensis. Journal of Human Evolution. 35 (1). 55 - 74.
>
stress the apelike features of australopiths & others like to stress the
humanlike features. In fact, Lucy & other australopiths had unique limb
features, some features looked like humans, some like chimps, some were
between the two, some were super-human, some super-ape ("mosaic"). Lucy, eg,
had a remarkably broad pelvis, short legs etc. What seems to be clear is
that australopiths form a cluster, IOW, austr.A looks more like austr.B than
like a chimp, in the same way that a chimp looks more like a gorilla than
like a human. The engineer-anthropologist C.E.Oxnard has perhaps done the
best studies in this field. He shows that the curved phalanges leave no
doubt that the australopiths were (partly) arboreal. On the other hand,
there is not much doubt that they were also (partly) bipedal. The Laetoli
footprints A & G show short steps, much shorter than in humans. IMO, the
solution for this problem is not so difficult. A combination of bipedality &
tree-climbing is exactly what is needed in swampy or frequently flooded
forests. This fits completely with where the australopith fossils are found.
And the electron microscopic studies of P.F.Puech fully confirm this & show
that they must have eaten AHV (aquatic herbaceous vegetation). This sort of
food is still a very small part (<2%) of the diet of some gorilla
populations. These western gorillas are more arboreal than mountain
gorillas, & wade in forest clearings in swamps where they eat herbs & sedges
(though their main food is THV & fruits). When we see the australopiths like
this, it's clear that humans as well as chimps & gorillas could all have
descended from some kind of bipedal forest or mangrove waders.
>The retention of some arboreal adaptations doesn't mean Australopithecines
>weren't also bipedal but I'm not sure how they fit into an adaptation to an
aquatic
>environment (it does show that they hadn't yet emerged fully into a
savannah
>environment either - unlike H.e.).
Dan, please forget everything you've ever read on human savanna ancestors.
There is not the slightest piece of evidence for it.
Marc
Marc Verhaegen
<360643ed...@nntp-serv.cam.ac.uk>...
...
>>>(But I have no doubt that elephants are ex-semi-aquatic, if you like such
>>>terms. Forest elephants spend a lot of time in water, savanna elephants
do
>>>this whenever they can, Indian elephants are between. Other pachyderms
like
>>>hippos & all 3 Asian rhino species are still semi-aquatic.)
>
>I was under the impression that they aren't particiularly closely
>related to elephants - I could be mistaken though...
>
& hyraxes. Hippos to whales. Rhinos to tapirs & horses.
...
>>Your 'elephant trunk as a snorkel' idea is just as silly.
>
>Silly perhaps, but true. Indian elephants in some areas swim short
>distances to offshore islands on a regular basis, and do indeed hold
>their trunks above the surface to breathe, rather than attempting to
>lift their entire head clear of the water - can't remember any more
>detail, but I've certainly seen film of this.
>
...
>An isolated instance of elephants swimming does not make them semi-aquatic.
>
I was not claiming that on that basis. Only that elephants "do indeed hold
their trunks above the surface to breathe".
Marc
Sherilyn
<lll...@thegrid.net> writes
>
>
If I remember correctly, Michael and others have promoted a
hybridization theory in the past. I believe Michael has related a
"recovered memory" account of personal alien-abduction experiences
involving fetuses and children stolen for hybridization experiments.
Aquatic/semi-aquatic adaptation by primates isn't unthinkable, other
mammals have undergone such adaptions. The connection with alien life
is tenuous, as Michael seems to have implicitly accepted.
Marc Verhaegen
Sherilyn heeft geschreven in bericht <6u2ncl$opa$1...@nnrp1.dejanews.com>...
...
>If you want to argue that _all_ apes are aquatically adapted,
>I guess if you find absence of apocrine glands in monkeys, that might be
useful.
>>
...
>> >> >The nose can be used as a form of signal, making human faces almost
>> >> >uniquely expressive in the animal kingdom. Perhaps this is evidence
>> >> >that signalling started early in humans, even before the development
of
>> >> >proper speech.
>> >> >
>> >> Sherilyn, such "unique" explanations are anthropocentric & therefore
IMO not allowed.
>> >> We have to use the comparative evidence. The most humanlike nose is
seen in
>> >> proboscis monkeys. Other mammals with external noses are: elephants,
tapirs,
>> >> suids, sea elephants, hooded seals.
>> >
>> >I strongly disagree with your suggestion.
>>
>> No, Sherilyn, after all, that's all we really have: the comparative
>> evidence. All the rest easily becomes speculation.
>
>That's what you're doing, don't you see? You see two animals with
>similar (not very similar, in many cases) adaptations, and you _assume_
>that they are due to the same cause.
No, I'm only seeing correlations.
>Then you call the similarity "comparative evidence."
Do you have another name?
...
>> (Or do you disagree that proboscis monkyes, elephants, tapirs, sea
>> elephants, hooded seals have external noses?)
>
>Looks like a non sequitur. Are you trolling me as you did over sexual
selection?
>>
>> >The only _evidence_ that would
>> >really be acceptable here would be that which can rule out one or other
just-so story.
>>
>> Yes, that's the comparative evidence.
>
>No, at this point I really think you are probably trolling for fun, to see
how much bad logic I will swallow.
No, really, I mean it.
I know I have an extremely adaptationalist view. But that's what evolution
is: all living creatures are incredibly adapted to their environment. If you
don't believe this, read only S.J.Gould & forget the ideas of Hamilton &
Maynard Smith & Dawkins etc.
It's very simple: look for external noses in other mammals. See what they
have in common. Conclusion: external noses are used for digging roots
(pigs), for finding insects (insectivores), for snorkeling (elephants,
proboscis monkeys), for making sounds (hooded seals), for sexual advertising
(elephant seals), for grasping food (elephants), etc. Now take another human
feature, say, SC fat, or furlessness, or large brain, or broad thorax... See
what these have in common & where these are overlapping. It's a puzzle, but
one that can be solved if you have enough data & comparisons. If you find
possible functional explanations, the better, but that's not essential
because many features are polyfunctional & the function changes during
evolution.
From my paper "Aquatic vs savanna..." Nutrition & Health 9:165-191 (1993):
External nose
An external nose is found in several semi-aquatics: a few seals, babirusa,
the tapirs etc., and in possible ex-semi-aquatics such as swine and
elephants. However, the same tendency is found in a few open country
dwellers (Günther's dikdik, saiga), and in several forest mammals (swine,
coati, and diverse insectivores). The only nonhuman primate with an obvious
external nose is the proboscis monkey, especially the adult males (Ellis,
1990). Functions are, e.g., intraspecific display (male bladder-nose and
elephant seal, proboscis monkey, saiga), manipulation of food (elephants,
tapirs, swine, dikdik and saiga, insectivores), snorkel (elephants,
proboscis monkey), and cooling (dikdik).
In spite of its absence in most savanna mammals, our external nose is
traditionally believed to protect against dust or dry air (Franciscus &
Trinkaus, 1988). Possible functions in an aquatic environment are obvious:
nose closing, and snorkel. If human ancestors dived for seaweeds or
shellfish just as several extant native populations still do), they could
surface and rest on their backs between two dives, as sea-otters do. In that
position our external nose would be well designed to keep it above the water
(in most mammals, especially carnivores, the nose is at the top of the head,
but less so in primates). Our largest para-nasal sinuses (the maxillary and
the frontal) are situated all round our nose, so the air in these sinuses
would greatly help to keep the nose above water. Floating on the back might
also have some relevance to the fact that many human males have more hair on
their chests than on their backs: this distribution pattern is not seen in
the apes, nor in other terrestrial mammals (except pangolins and
armadillos). It might also explain why Neandertals and certainly Homo
erectus developed such very dense occipital bones, which made the dorsal
side of the bead much heavier than the ventral side. The auditory canals of
their skulls often show exostoses of a kind that is only seen in humans that
swim almost daily in water colder than 18-20°C (Kennedy, 1986).
Marc Verhaegen
>>From my 1993 paper "Aquatic vs savanna..." Nutrition & Health 9:165-191:
Then again, try to think a bit:
1) why are we the only mammal that is building an arched support to bear his
weight?
2) why do you think that increasing surface area for more effective
locomotion is incompatible with building an arched support to bear his
weight?
>The claim that "every bipedally striding mammal develops humanlike feet"
>is a strawman. I've never heard *anyone* suggest such a thing, other than
>yourself. Similarly, the idea that aquatic or semi-aquatic mammals
>evolve human-like feet is also a unique absurdity that I've only heard from
>you. You've also suggested that elephants evolved from an aquatic
ancestor--
>are you going to suggest that they have human-like feet, too?
>
Emotional arguments.
Please just look at the foot skeletons of the animals I mentioned.
Why do you think I ever claimed that we were seals or whales or seacows?
>This is a very
>misleading suggestion. In *none* of the fossil hominids seen so far is
there
>any evidence of the kind of short, robust hindlimbs seen in aquatic
mammals.
>
>And now you want to argue that our ancestors were flamingo-like waders
>rather than divers? Get your story straight, please.
DID CHIMP AND GORILLA FOREBEARS WALK ON TWO LEGS?
Humans are very peculiar primates, and they must have had a special
evolution. Nevertheless, they evolved within the same biological constraints
as all other mammals. We think much can be learned by studying the parallel
or convergent adaptations of different animals in similar environments, and
new insights in our evolution might be gained by consistently comparing
human and hominid features with those of other species (comparative anatomy
and physiology).
Only five years ago, the anthropological consensus was that bipedalism
appeared in a savanna environment about 4 Myr BP (million years before
present). But the available fossil evidence now suggests that it happened in
a forested habitat and that the date ought to be set further back (e.g.
White et al., 1994; Andrews, 1995). According to the molecular data, the
pongids (Pongo) and the hominids (Gorilla, Pan, Homo) broke into two groups
some 10 Myr BP. Then the forebears of the gorillas and those of humans and
chimps split apart about 8 or 6 Myr BP. Most recently the ancestors of the
chimpanzees and those of humans separated between 6 and 4 Myr BP (e.g. Kumar
& Hedges, 1998). This means that the last common ancestor of gorillas,
chimpanzees and humans may have been a forest dweller that walked part of
the time on its hindlimbs.
Most primates are arboreal quadrupeds with mobile joints and limbs that can
be straightened to reach other branches. This locomotor flexibility allows
them to adopt a bipedal gait with extended knees and hips when wading
through shallow water (and not the leaping bipedality that some primates use
when moving on the ground). For example, proboscis monkeys Nasalis larvatus
cross stretches of water to reach other mangrove trees walking on two legs,
and lowland gorillas G. g. gorilla go wading on their hindlimbs through
forest swamps to supplement their diet with swamp herbs and sedges (see
below AHV). In the same way, we suggest the earliest hominids might have
been bipeds part of the time, wading in tidally or seasonally flooded
forests.
The hominids, present in Africa at least since 6 Myr BP, radiated into the
australopithecines, African apes and humans. Several side-branches may have
gone extinct. It may be expected that direct ancestors of living species are
rarely found in the fossil record (e.g. Nelson, 1998), and that the fossil
hominids are extinct side-branches of the living species. Since
fossilisation is especially difficult in mangrove areas, the inland
offshoots are more likely to be discovered.
Many of the more inland branches in lagoons, estuaries and rivers must have
evolved in parallel. As they followed the rivers upstream, shellfish became
rarer, the shellfish part in the diet was gradually replaced by plant food,
and step by step they became more herbivorous and terrestrial again. Since
the hominids first split into Gorilla at the one hand and Homo-Pan at the
other (about 8 or 6 Myr BP), the Gorilla branch might have been the first to
colonise the African inland. Presumably they did so along the rivers of the
Rift Valley, and eventually became herbi-folivorous. The Pan branch, one or
two million years later, followed and developed parallel features, but
generally remained more omni-frugivorous and more arboreal. Knuckle-walking
in African apes has been argued to be derived from the early hominid
short-legged bipedalism (e.g. Kleindienst, 1975; Edelstein, 1987). Since
their ancestors’ interlude of frequent wading and shellfish collecting was
probably short and partial and long ago, few traces would remain in
present-day chimpanzees and gorillas. In some ways, we can view many changes
as a U-turn back to the ancestral lifestyle of non-hominoid primates.
Features like bipedal gait, tool use, dextrous hands, enlarged brains or
thick enamel might diminish or disappear.
Presumably the earliest hominids had thick enamel (Martin, 1985), like most
earlier and later relatives, for instance, Siva-, Ourano- and Ankarapithecus
(e.g. Cameron, 1997; Algaput et al., 1996) and the australopithecines
(without ramidus, see White et al., 1994; Andrews, 1995). Developmental
mechanisms to account for the thick and thin enamel in hominoids have been
proposed by Martin (1983, 1985). Thick enamel is typical of capuchin monkeys
or sea otters that eat hard-shelled foods like nuts or molluscs (Fernandes,
1991; Walker, 1981). In the sea otters, it is perhaps not for cracking the
shells, but for the occasional hard inclusions, which could otherwise damage
the dentition (Walker, 1981). Ancestral features such as thick enamel and
rounded bunodont cusps, presumably linked to the procession of hard foods,
may have undergone an evolutionary reversal, showing more reduction in the
African apes than in the orang-utans, which still consume more hard-shelled
fruits (Puech et al., 1984).
The early australopithecines had enamel microwear features, such as a
polished surface with glossy appearance, resembling those of marsh plant
feeders like mountain beavers Aplodontia rufa and capybaras Hydrochoerus
hydrochaeris (Puech et al., 1986). They typically dwelt in swale-like
streamside gallery woodlands (e.g. Radosevich et al., 1992; Rayner et al.,
1993). This is where they might have waded bipedally in search of aquatic
herbaceous vegetation (AHV). Presumably they did this in the same way, but
regularly instead of occasionally, as the western lowland gorillas do in the
shallow swamps of the tropical forest clearings (Chadwik, 1995; Doran &
McNeilage, 1997).
The robust australopithecines then evolved smaller front teeth, but still
broader back teeth with thick and heavily worn enamel with deep recessed
dentine (e.g. Puech, 1992). This suggests they supplemented fruits and AHV
with woody or hard plant material such as nuts, bark, pith, roots, cane or
bamboo (Walker, 1981; Puech et al., 1986; DuBrul, 1977).
In the meantime, a part of the population was left behind at the coasts.
???
Why do these suggest that??? what makes you believe that???
No, we are unique, and so is PZ Meyers.
Marc
Marc Verhaegen
>In article <36055C72...@thegrid.net>, Lorenzo L. Love
><lll...@thegrid.net> writes
>>
>>
>>Marc Verhaegen wrote:
>...
>>> >
>>> Hurray, the first +-sensible thing of LLL.
>...
>>
>>More lies and distortions.
>
>Have you guys been taking lessons from Michael?
>
>The AAT certainly seems to attract a lot of kooky behavior.
>Sherilyn
>Grad Student, University of Ediacara
>
talking about calls me a liar, I may answer, no?
(And I was really glad to read something sensible of LLL.)
Marc
Marc Verhaegen
PZ Myers heeft geschreven in bericht ...
>In article <6u2b25$s8v$1...@xenon.inbe.net>, "Marc Verhaegen"
>>Matt Silberstein heeft geschreven in bericht
>>...
>>>Ok, so what is your point? Are you claiming that the elephant is an
>>>(semi-) aquatic animal? If so, you seem to have redefined the term.
>>>>
>>I'm saying that elephants have been seen using the proboscis as a snorkel.
>>
>>terms. Forest elephants spend a lot of time in water, savanna elephants do
>>this whenever they can, Indian elephants are between. Other pachyderms
like
>>hippos & all 3 Asian rhino species are still semi-aquatic.)
>>
>
>Have you ever heard of Darwin's story for the evolution of whales? He
>suggested that they could have evolved from swimming bears snapping at
...
>Your 'elephant trunk as a snorkel' idea is just as silly...
...
No. Just read, eg, D.Quammen 1996, "The song of the dodo" Schuster NY, on
elephants.
Darwin had an enviable imagination, and though he lived 150 years ago, with
all of his flimsy anecdotes he did excellent work.
(Do you care what creationists think??)
Besides, you have to think a bit deeper. I never claimed the elephant's
trunk in its present form is an aquatic adaptation. But the comparative
evidence suggests that its trunk originated as some kind of snorkel - as in
tapirs & proboscis monkeys & humans & hooded seals & elephant seals.
Marc
myke_r...@yahoo.com
> Dan Barnes wrote:
>
> > PS - anyone know why this is being crossposted to alt.alien.visitors? Is
this the
> > next step for AAT - that our ancestors evolved on a water planet in another
solar
> > system!
>
> Isn't that what Reynolds is pushing? And given the improbability of aquatic
apes,
> wouldn't alien intervention be required to make it happen?
>
Sherilyn initiated this thread. About 16 months ago, I profered AAT
as a straight forward assertion that humanoids would be a relatively
common form of evolution in exo-biology. That was the first and last
time I ever mentioned it, because we argued about AAT exclusively ever
since; save for the occasions when Sherilyn would bring the original
context up in much the same manner as yourself, as a polemic tool
of rhetoric used to dismiss the argument without addressing it.
Given the impossibility of your status quo explanation for
dealing with plausible non-aquatic selective pressues that would
produce horizontal, linear symmetry vs. vertical, perpendicular
symmetry, it is your explanation, and not AAT's, that would
require overt intervention in early evolution to accomplish.
myke_r...@yahoo.com
> In article <3606A840...@thegrid.net>, Lorenzo L. Love
> >> PS - anyone know why this is being crossposted to alt.alien.visitors?
> >> Is this the next step for AAT - that our ancestors evolved on a water
> >> planet in another solar system!
> >
> >Isn't that what Reynolds is pushing? And given the improbability of
> >aquatic apes, wouldn't alien intervention be required to make it
> >happen?
>
> hybridization theory in the past. I believe Michael has related a
> "recovered memory" account of personal alien-abduction experiences
> involving fetuses and children stolen for hybridization experiments.
This is entirely false. There is no resemblance to my stated conjecture
here, nor an explanation for why Sherilyn initiated the thread with AAV
in the distribution list. The real reason is purely polemic: guilt by
association. Since she can't saliently address the argument, this is
the most effective rhetorical/polemic technique available to her. Note
again: Sherilyn initiated this thread with AAV on the distribution list,
not myself.
> Aquatic/semi-aquatic adaptation by primates isn't unthinkable, other
> mammals have undergone such adaptions. The connection with alien life
> is tenuous, as Michael seems to have implicitly accepted.
No, your reason for cross posting is what is tenuous. The correctness
of AAT has an immediate correlary with regards to possible paths of
evolution of life on other planets. But this issue is completely moot
if AAT is not already accepted as correct. Sherilyn only brings it
up as a polemic technique to distract from the vacuous weakness of
the anti-AAT argument.
myke_r...@yahoo.com
> Myers <my...@netaxs.com> writes
> >Compare a pinniped and a human, and you can see that they've been going
> >better swimming. They don't exhibit any of the anatomical characteristics
> >well in terrestrial locomotion. I would argue that if we *had* gone partway
> >down the road to an aquatic lifestyle, that would rather effectively
> >cripple our ancestors and prevent them from returning to the land. How
> >successful do you think a seal or a sirenian would be if it decided to
> >give up on the sea and hunt or graze on the land?
> >
> Hmm, on the question of a sirenian I have to agree, and you have
> effectively rebutted Michael's admittedly poor argument.
Sirius? Is that where this rebuttal comes from?...
This is in no way a rebuttal of my argument since quadrupeds are
going to react entirely differently to these morphological changes
than primates. There is no way that these morphological changes
could ever result in a quadruped becoming bipedal. Primates, on
the other hand, would automatically have the potential to become
bipedal as a result of these changes, and what is more, they
would have dramatic benefits to reap, producing strong selective
pressures. The advantage being the freeing of their prehensile
digits. Quadrupeds could never have any advantage by becoming
bipedal, and thus, there could be no selective pressures for
this. You acknowledge the lack of selective pressures in this
regard to pinnipeds, and then falsely compare this to primates who
would not in any way be similarly lacking in selective pressures
to take advantage of the obvious benefit of the bipedal locomation
available to them.
Your analysis of selective pressures is flawed. You have simply
avoided the principle argument for AAT, without acknowledging
the issue of selective pressures that automatically favour
this morphology in animals with prehensile fingers. Your
basic argument is that, because no quadruped became bipedal
this way, that no other category of animal could either.
That is a blanket statement that glosses completely over
the essential issues. Penguins, for example, developed
similar locomotion in precisely the same manner, albiet
less efficient locomotion. But never the less, they developed
an identical posture as a result of nearly identical selective
pressures. They were bipedal to start with, so the only possible
outcome of marine evolution was fully upright bipedalism.
Similarly, the dramatic advantage of the freeing of prehensile
digits on the forelimbs makes upright bipedalism the most
likely outcome of marine evolution of a primate.
> One thing that
> now strikes me about the AAT, which I first encountered in '76 in the
> form of Elaine Morgan's The Descent of Woman, is that it's rather like
> the Face on Mars, a myth that NASA exploded with obvious glee earlier
> this year. Both seem to be acting as a proxy for some internal
> struggle.
The reliance on blanket dismissals that fail to even remotely address
the issue of selective pressures that could potentially lead to
bipedalism is far more reflective of this, in my opinion. It is one
thing if the argument is rebutted and rejected, but it is something
else entirely if the argument is rejected without even remotely salient
rebuttals. This is indicative of severe paradigm blindness and
emotional rather than logical reasoning.
===============================================================
BTW, I've never been able to understand why either proponents or
skeptics focus so much on the face on Mars when there is supposedly
several pyramids in the area, at least one purported by proponents
to be clearly defined. The vague outline of a face could be argued
forever as to whether it is artificial or natural. True pyramids, on
the other hand, if they exist, could never be argued to be natural.
The salient issue is the pyramids. The falsehood or validity of
the issue rests solely on the viability of the pyramids, not the
face, but neither side addresses the issue in this perspective.
That is a case where the proponents of the artificial structure
theory are just as out to lunch as the critics. In the case of
AAT, it is only the skeptics who fail to address the critical
issues.
myke_r...@yahoo.com
> And I thought only Michael Reynolds was dim enough to seriously advance
> this '180° leg/trunk angle' idea...
You have failed to ever demonstrate a meaningful understanding of
the assertion, as demonstrated by your inability to post a salient
rebuttal. Your rebuttals invariably fail to address the salient
supporting points for the assertion. Instead, you just flatly
dismiss the issue and create an essentially unrelated argument
for why you do so. The assertion may be false, but if you fail
to saliently address the supporting points for the assertion,
then your argument is less than convincing.
C. Kevin kellogg
: Sherilyn heeft geschreven in bericht <6tv4jr$ar1$1...@nnrp1.dejanews.com>...
: >There's no law of nature that says things have to turn out a certain way.
: If you are a mammal & you're adapting to aquatic life, at some point, you
: will loose your fur, because all fully aquatics are furless. So we can say:
: if you are fully aquatic, you "must" have lost your fur.
Most pinnipeds (seals, sealions, walruses, etc.) retain fur, as do
aquatic mustelids (otters, and sea otters). All of which are far better adapted
to aquatic life than humans.
C. Kevin Kellogg
myke_r...@yahoo.com
It is fairly straight forward that different features of aquatic
adaptation can evolve at different rates depending on selective
pressures. While AAT is based in part on comparisons with marine
mammals, it does not assert that all the selective pressures were
operating in early hominids with precisely the same force as on marine
mammals. This is a common mistake made by skeptics who pose false
assertions about what AAT should predict.
Clearly the switch from vertical/perpendicular to horizontal/
linear alignment can precede the loss of fur. Once this switch has
occurred, quadrupeds are under much heavier pressures to become fully
aquatic as rapidly as possible, since terrestrial locomotion becomes
so cumbersome. As such, the fur, with the evolution of added body oil,
is readily recruited as essentially needed insulation before it is
replaced completely by subcutaneous fat. They don't have time to
wait for subcutaneous fat to evolve and they desperately need
insulation.
Neither of these two selective pressures are present for early semi-
aquatic hominids. They were not forced into accelerated evolution of
other aquatic features by a loss of terrestrial locomotive efficiency.
They are hypothesized to have first evolved on islands in a temperate
region during the warmer Pliocene. On the rare occasions when it did
get a bit nippy, they could just pop out of the water, so there was
no great selective pressure for them to hang on to any insulation
they could. Indeed, we don't even have very much subcutaneous fat
as compared with other marine mammals. There simply isn't the same
pressures on early aquatic hominids to evolve insulation.
Despite the fact that sea otters are definitely better adapted to marine
life, their adaptation is also very recent and rapid. One of the results
of shifting from vertical/perpendicular alignment to a horizontal/linear
alignment is belly to belly mating. Sea otters are so close to their
terrestrial mustelid ancestors that they have not yet lost the obsolete
instinct of the male attempting to bite the back of the female's neck to
hold her in place during mating. Since they mate exclusively belly to
belly now, at the end of every mating season, all adult females have
bloody noses. Sea otters are recent arrivals to the ocean.
Pinnipeds, not quite so recent, have a thinner layer of fur that is more
fine, evidence of longer aquatic evolution, and Cetacea and Sirenea have
none at all. So while marine mammals have much greater selective
pressures to adopted other aquatic features more rapidly, precisely
the reverse is true with fur. Though there is a general tendency to
loose fur over time, the selective pressures are less strong than
they would have been for early semi-aquatic hominids, who had no
great need for insulation to produce selective pressures to keep
fur. Instead, the aquatic advantages of fur loss would have played
a much greater role, with no special need for insulation to produce
selective pressures counter to this.
Note: the evolution of substantial body oil and belly to belly
mating are two key features of AAT in addition to fur loss and
horizontal/linear symmetry.
myke_r...@yahoo.com
> Sherilyn heeft geschreven in bericht <6tv096$6ec$1...@nnrp1.dejanews.com>...
> >[Michael wrote]
Almost two years ago:
> >> >>1) If human beings are not semi-aquatic, then primate is the only order
> >> >>of mammal without an aquatic member.
> >> Exaggeration.
> >
> >Agreed. Michael's argument was an exaggeration.
I recanted this two years ago and admitted repeatedly that I
could not recall specifically what Desmond Morris referred to when
he stated that humans belong to some category of animal that would
be the only such category to have no aquatic member if humans are
not. It was in fact the very FIRST point that I dropped from my
initial list of points supporting AAT. One of only three such
points that I dropped. (And one of those three I have just
reformulated.)
You are proving the title of the thread to the negative, Sherry.
You still have never addressed the only supporting argument that
I put forward this year, prior to today. That is quite a rhetorical
twist to completely skip over rebutting my current argument in
favor of rebutting an argument I dropped two years ago. You did
this constantly in the original argument, though not in nearly
such a dramatically obvious polemic fashion.
myke_r...@yahoo.com
> Lorenzo L. Love writes:
>>More lies and distortions.
>
>Have you guys been taking lessons from Michael?
I never sank to the level of calling anyone a liar. Polemic and
rhetorical, facile yet loud mouthed, yes. However, these are not
ad hominems either. You are apparently not capable of directly
rebutting the argument, so you attempt to dredge up the very
weakest of my arguments from 2 years ago that I explicitly dropped.
At least Mr. Love can coherently stick to the subject matter.
I much prefer this in debating opponents to lack of ad hominems.
In fact, it is quite essential to any kind of coherent debate.
>The AAT certainly seems to attract a lot of kooky behavior.
>--
>Sherilyn
>Grad Student, University of Ediacara
If nothing else, you can certainly speak for yourself, Mr. Sherilyn.
myke_r...@yahoo.com
> >> small and medium sized aquatics and semi-aquatics, it has a nice coat of
fur.
> >
It neither supports nor contradicts the argument. It is immaterial.
See new thread, AAT & fur.
> Of course. You don't know Michael very well if you don't yet realize that
> every piece of evidence somehow supports his argument.
That is easy to say when you have never saliently addressed the
principle argument put forward.
myke_r...@yahoo.com
> my...@netaxs.com (PZ Myers) wrote:
> > Of course. You don't know Michael very well if you don't yet realize that
> > every piece of evidence somehow supports his argument.
>
> he has to economize with the evidence.
Mass murderer...? Now there is a salient rebuttal if I've ever
seen one! What planet did you teleport in from, Mr. Sherilyn?
<Ode to Rocky Horry Picture Show omitted> =8^)
I apologize to the rest of SAP for having dragged in nut
cases like Sherilyn from sci.skeptic. This is my last
cross posting to sci.skeptic. And unless I see Marc
significantly falter, this is my last posting on the
subject. He is doing an excellent job, far better than
I can on the great majority of issues.
myke_r...@yahoo.com
post on the subject: SAP was of great help to me not only in refining
my argument, but in general, I learned a great deal from SAP posters
about biology that I found fascinating and knew nothing about before
hand. SAP posters were worthy opponents who produced excellent
arguments, with the sole exception of Mr. Nichols, and I was very
enriched by the overall experience.
Sci.skeptic on the other hand exclusively produces such salient
rebuttals as repeated counters to arguments dropped two years prior.
The following is one of the 3 points that I conceded for lack of clear
evidence available to me. It was one of the points made by Desmond
Morris, so take it up with Desmond Morris, I dropped this point 2 years
ago.
Please note also that PZ Myers, John Cason, and Sherilyn are all
imports from sci.skeptic. I will not debase your forum by attracting
these unsavory types any longer.
"John Cason" <jkc...@negia.net> wrote:
> Don't forget the point about ability to constrict the nose. Aquatic bats
> have fur and many species can close their nasal passages. As can camels,
> who also have fur. Their ability to vary the water content of their bodies
> was originally a way to adjust bouyancy for better bottom-feeding.
> Likewise, the large, furry, semi-aquatic North American moose obtains a
> substantial part of its diet by eating algal mats on the bottom of shallow
> lakes. It should be able to constrict the nasal passages, and subcutaneous
> fat would come in handy in that cold water. Not to mention where we find
> all the good moose fossils. QED.
>
> This modern biology is lots more fun than the old, plodding biology that
> used to be taught in school.
PZ Myers
This is ridiculous. Your claims consist solely of contrived correlations--
"every animal that has X is a marine mammal or a human, therefore
humans shared a similar evolutionary history with marine mammals".
Whenever differences are pointed out, you either ignore them or say
that this is one area in which humans are allowed to have had a unique
history.
>
>Your analysis of selective pressures is flawed. You have simply
>avoided the principle argument for AAT, without acknowledging
>the issue of selective pressures that automatically favour
>this morphology in animals with prehensile fingers. Your
>basic argument is that, because no quadruped became bipedal
>this way, that no other category of animal could either.
>That is a blanket statement that glosses completely over
>the essential issues. Penguins, for example, developed
>similar locomotion in precisely the same manner, albiet
>less efficient locomotion. But never the less, they developed
>an identical posture as a result of nearly identical selective
>pressures. They were bipedal to start with, so the only possible
>outcome of marine evolution was fully upright bipedalism.
>Similarly, the dramatic advantage of the freeing of prehensile
>digits on the forelimbs makes upright bipedalism the most
>likely outcome of marine evolution of a primate.
Again, ridiculous. There is no necessity here -- at least, you have
certainly shown me nothing to convince me that "prehensile fingers"
+ aquatic life leads to bipedal locomotion, other than your standard
argument from a correlation with *one* animal, us.
You've also dodged my criticism. The adaptations that marine mammals
exhibit tend to compromise the ability of the pelvis and hindlimbs to
support bipedal locomotion. They also tend to promote some characteristic
anatomical changes that we simply do not have. Conjuring up putative
"selective pressures" that drive this hypothetical marine ancestor to
rear up on two legs on land doesn't work -- evolution isn't simply
about automatically acquiring whatever traits we think look desirable,
organisms have to live with the limitations and potential of their
ancestry. Also, given your kind of thinking here, if the "selective
pressures" to free up and use the forelimbs are so great, why can't they
also drive modifications to terrestrial primates?
>
>> One thing that
>> now strikes me about the AAT, which I first encountered in '76 in the
>> form of Elaine Morgan's The Descent of Woman, is that it's rather like
>> the Face on Mars, a myth that NASA exploded with obvious glee earlier
>> this year. Both seem to be acting as a proxy for some internal
>> struggle.
>
>The reliance on blanket dismissals that fail to even remotely address
>the issue of selective pressures that could potentially lead to
>bipedalism is far more reflective of this, in my opinion. It is one
>thing if the argument is rebutted and rejected, but it is something
>else entirely if the argument is rejected without even remotely salient
>rebuttals. This is indicative of severe paradigm blindness and
>emotional rather than logical reasoning.
I've noticed in your recent spate of posts that "salient" seems
to be your word for the day.
I think you should look up the definition. It does not mean "compatible
with Michael Reynold's reasoning". The word you are looking for is
"vacuous".
>
>===============================================================
>
>BTW, I've never been able to understand why either proponents or
>skeptics focus so much on the face on Mars when there is supposedly
>several pyramids in the area, at least one purported by proponents
>to be clearly defined. The vague outline of a face could be argued
>forever as to whether it is artificial or natural. True pyramids, on
>the other hand, if they exist, could never be argued to be natural.
>The salient issue is the pyramids. The falsehood or validity of
>the issue rests solely on the viability of the pyramids, not the
>face, but neither side addresses the issue in this perspective.
>
Oy. I've been wasting my time arguing with a lunatic.
>That is a case where the proponents of the artificial structure
>theory are just as out to lunch as the critics. In the case of
>AAT, it is only the skeptics who fail to address the critical
>issues.
Michael Reynolds: the crackpot's crackpot.
--
PZ Myers
Sherilyn
myke_r...@yahoo.com wrote:>
> Note: the evolution of ...belly to belly
> mating [is a ] key feature of AAT
...
Have bonoboes ever undergone aquatic adaptation? They often
mate belly-to-belly, and are believed to be our closest living
relatives.
--
Sherilyn
Sherilyn
myke_r...@yahoo.com wrote:
> "Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
> > Sherilyn heeft geschreven in bericht <6tv096$6ec$1...@nnrp1.dejanews.com>...
> > >[Michael wrote]
> Almost two years ago:
Just over one year ago.
>
> > >> >>1) If human beings are not semi-aquatic, then primate is the only order
> > >> >>of mammal without an aquatic member.
>
> > >> Exaggeration.
> > >
> > >Agreed. Michael's argument was an exaggeration.
>
> I recanted this two years ago and admitted repeatedly that I
> could not recall specifically what Desmond Morris referred to when
> he stated that humans belong to some category of animal that would
> be the only such category to have no aquatic member if humans are
> not.
...
Upon Michael did grudgingly admit that he had misinterpreted something
Desmond Morris had said. For instance:
I have admitted that my "if human's are not aquatic then primate is
the only major order without an aquatic member" is definitively wrong.
I don't remember what the exact statement by Desmond Morris was,
but it was something similiar, though obviously distinct.
And of course I don't deny that Michael has changed his position.
The posting was a repost from early June, before Michael dropped his
claim, and was in rebuttal to Michael's claim that I had never addressed
his arguments. Michael conveniently forgets such things when it suits
him to make a cheap shot.
Sherilyn
>
> You are proving the title of the thread to the negative, Sherry.
> You still have never addressed the only supporting argument that
> I put forward this year, prior to today.
As far as I am aware, you have put forward no supporting arguments
this year for the claims upon which you and I have expressed a
difference of opinion, namely your claims:
That the AAT is the dominant theory of human evolution
That the AAT is incontrovertible
That the AAT predicts anything about the morphology of
hypothetical intelligent, spacetravelling aliens.
Please advance any arguments you have for any of the above claims,
and I will consider them. Arguments in favor of the AAT are just
fine; as I stated back in April, 1997, and have expressed ever since,
I do not oppose the AAT.
Elaine Morgan
>> I believe, eccrine sweat glands are present in apes, but much less
than in
>> humans.
>> Do monkeys have many eccrines?
All monkeys and almost all non-hoofed mammals have eccrines on palms and
soles. (cats, dogs, rats etc etc.+) South Americam omkeys have them also
on their prehensile tais and apes on their knuckle-pads. Monkeys in
general, unlike non-primates, are liable to have a scattering of them
over the the body surface. The apes have more - about 50/50 apocrine and
eccrine - but their eccrine glands respond to emotion rather than to
temperature as ours do.
>
>.
>>
>> > If modern humans need more sweat glands (we do, after all, have
>> >radically different lifestyles than most apes, and we don't know how
>> >recent the widespread sweat glands are) then an aquatic phase would be
>> >superfluous.
Anaquatic phase might be superfluous if this were our only anomalous
feature rather than about ninth on the list. I believe we lost body hair
first, and that deprived us of our hereditary defence against the sun's
heat; therefore the eccrines which as primates we had acquired became
much more numerous and exuded more moisture than in any other living
mammal.
>-
Elaine
Marc Verhaegen
Elaine Morgan heeft geschreven in bericht ...
>>>
>>> I believe, eccrine sweat glands are present in apes, but much less than
in humans.
>>> Do monkeys have many eccrines?
>
bodies?)
>All monkeys and almost all non-hoofed mammals have eccrines on palms and
>soles. (cats, dogs, rats etc etc.+) South American monkeys have them also
>on their prehensile tails and apes on their knuckle-pads.
Yes.
It might be interesting to know that human fetuses develop the palmar &
plantar eccrines during the 4th month, at about the same time when we
develop our fingerprints. Both these eccrines & fingerprints probably form
an anti-slip device.
>Monkeys in
>general, unlike non-primates, are liable to have a scattering of them
>over the the body surface. The apes have more - about 50/50 apocrine and
>eccrine - but their eccrine glands respond to emotion rather than to
>temperature as ours do.
Yes, gorillas sweat "territorially" (I believe Fossey wrote you can smell
them a kilometre away), but also thermoregulatory. (Like humans, but in
different ratios?) Sweat itself is odourless, I believe, but skin bacteria
make it smell.
Do you know whether there are differences in body eccrines between New & Old
world monkeys? & prosimians? Is there a gradation human > Afr.apes >? orang
>? gibbons >? OWMs >? NWMs?
Marc
Marc Verhaegen
C. Kevin kellogg heeft geschreven in bericht
<6u6sk0$2or$2...@gondor.sdsu.edu>...
>Marc Verhaegen (Marc.Ve...@village.uunet.be) wrote:
>: Sherilyn heeft geschreven in bericht <6tv4jr$ar1$1...@nnrp1.dejanews.com>...
>
>: >There's no law of nature that says things have to turn out a certain
way.
>
>: If you are a mammal & you're adapting to aquatic life, at some point, you
>: will loose your fur, because all fully aquatics are furless. So we can
say:
>: if you are fully aquatic, you "must" have lost your fur.
>
> Most pinnipeds (seals, sealions, walruses, etc.) retain fur, as do
>aquatic mustelids (otters, and sea otters). All of which are far better
adapted
>to aquatic life than humans.
This has been discussed at length in SAP.
In short:
- Furlessness is seen in all fully aquatics, all very large aquatics, some
tropical mammals (pachyderms, babirusa, naked molerat, naked bat),
domesticated dog & pig.
- Aquatics are only furless if they are very big, if they are fully aquatic,
& in some tropical ones (hippo, babirusa).
- All semi-aquatics are furred except the very big ones (male Steller
sealion, walrus, elephant seal) & except a few tropical semi-aquatics (eg,
hippo, babirusa).
- Some tropical mammals that sleep in holes are sparsely haired (aardvark,
hunting-dog, warthog).
Conclusion: our furlessness does of course not prove that humans spent a lot
of time in the water, but it's a strong argument. It also strongly suggests
that our ancestors were (sub)tropical - but that's no news.
Marc
Marc Verhaegen
>> Note: the evolution of ...belly to belly mating [is a ] key feature of
AAT
>...
>Have bonoboes ever undergone aquatic adaptation? They often
>mate belly-to-belly, and are believed to be our closest living relatives.
Some aquatic adaptation (frequent wading & swimming, but probably not
diving), yes, like all (great) apes. See our paper "Chimp & gorilla
forebears walked on 2 legs".
And from my 1993 paper "Aquatic vs savanna..." Nutr.Health 9:1965:
One of the problems that remain is that many features which might be aquatic
rudiments are also seen - often less overtly - in the apes. If we do not
want to explain all these as arboreal features (e.g., branch-hanging
adaptations) that were preadaptive for an aquatic habitat, the only
conclusion is that the apes (or at least the great apes) went through a
semi-aquatic stage less pronounced and/or less long-lasting than the human
(Verhaegen, 1985).
These features possibly include: tendency to nakedness (absence of underfur
in the great apes, nakedness in ape fetuses and in several anatomical
regions), proneness to obesity (old apes in captivity), intermediate density
of eccrine skin glands (notably in the African apes), subdivided kidney
papillas (chimp), more humanlike feet (highland gorilla and prenatal African
apes), occasional bipedality (especially in gibbons and bonobos),
ventro-ventral copulation (in orangs and often in bonobos), broad thorax (at
the same time barrel-shaped in gibbons), slightly descended larynx (apes),
extensive pneumatisation (great ape skulls), rather high encephalisation,
very long lactation, childhood and life span. Possible ex-aquatic
adaptations not discussed above include: large body size in the great apes,
absence of a tail, round breasts in female orangs (Schultz, 1941, 81); and
not seen in humans: sternal organ of sebaceous glands in orangs (Schultz,
1941, 81), lower limbs shorter than upper limbs, small ears in gorillas and
orangs (Schultz, 1936). (Some of these features could also be explained by
arm-hanging or brachiation: tendency to truncal erectness, ventro-ventral
copulation, broad and/or barrel-shaped thorax, arms longer than legs.)
Marc
Sherilyn
writes
>Sherilyn heeft geschreven in bericht ...
>> Lorenzo L. Love writes:
>>>More lies and distortions.
>>
>>Have you guys been taking lessons from Michael?
>
>I never sank to the level of calling anyone a liar.
True, you called me many other names, but we'll pass over that.
...
>You are apparently not capable of directly
>rebutting the argument, so you attempt to dredge up the very
>weakest of my arguments from 2 years ago that I explicitly dropped.
No, you quoted _only_ one of about a dozen arguments I challenged just
over _one_ year ago, from an article I posted in rebuttal of your claim
that I had never addressed the AAT, or rather your own misconceptions
about it.
Sherilyn
writes
>Sherilyn <Sher...@sidaway.demon.co.uk> wrote:
...
>>
>> If I remember correctly, Michael and others have promoted a
>> hybridization theory in the past. I believe Michael has related a
>> "recovered memory" account of personal alien-abduction experiences
>> involving fetuses and children stolen for hybridization experiments.
>
>This is entirely false. There is no resemblance to my stated conjecture
>here,
See another posting in this thread quoting one of Michael's recovered
memory accounts of going on a killing spree in an alien spacecraft where
hybridization experiments were being carried out.
> nor an explanation for why Sherilyn initiated the thread with AAV
>in the distribution list.
Michael initiated this thread in aav by referring to his experience last
year in sap. I corrected his misstatements.
...
>
>No, your reason for cross posting is what is tenuous. The correctness
>of AAT has an immediate correlary with regards to possible paths of
>evolution of life on other planets.
...
A statement Michael has repeatedly made but has never been able to
justify.
Sherilyn
writes
>Sherilyn <Sher...@sidaway.demon.co.uk> wrote:
>> my...@netaxs.com (PZ Myers) wrote:
>> > Of course. You don't know Michael very well if you don't yet realize that
>> > every piece of evidence somehow supports his argument.
>>
>> Being a self-proclaimed genius scientist and mass murderer isn't easy;
>> he has to economize with the evidence.
>
>Mass murderer...? Now there is a salient rebuttal if I've ever
>seen one!
Michael, go to a dictionary and look up the meaning and usage of the
word _salient_. The account of mass murder is your own, by the way.
[excerpt from a long post]
...
"The most dramatic experience was when I was 12, and as
a result of puberty, I was able to break free and had my run
of the ship. I went on a killing spree and managed to make
my way to the incubatory room with the fetuses. The fish
tanks the alien hybrid fetuses were in were solidly
mounted, but the lids could be opened, so I started
pulling them out and breaking their necks. If you know
anything about the alien attitude toward these hybrid
fetuses, you'd immediately understand my motivation
here. It's a bit much to describe here, but I'm most
certain not a homicidal maniac under any other
conditions.
...
At the time, the only other thing I noticed was that,
when visiting my girlfriend and petting her pet
rabbit, I found myself cognating on the fact that
the rabbit's neck was so thin I could break it in
a moment. I have always had a fondness for
animals and had many pets myself. The feeling
was not overpowering, but it was clear and
distinct and left me feeling very disquieted and
utterly perplexed."
Sherilyn
writes
In article <6u71p8$egm$1...@nnrp1.dejanews.com>, myke_r...@yahoo.com
writes
...
>About 16 months ago, I profered AAT
>as a straight forward assertion that humanoids would be a relatively
>common form of evolution in exo-biology.
An argument he has never been able to support, though I have repeatedly
asked him to do so.
> That was the first and last
>time I ever mentioned it, because we argued about AAT exclusively ever
>since;
False. I have corrected Michael's misstatements of the AAT, a
hypothesis that I think is quite feasible and workable, but to which I
am not committed.
Lorenzo L. Love
Marc Verhaegen wrote:
How can it be a strong argument for aquaticism when the very reasons you list
argue against any hairless mammal below 50 kg being aquatic? If you want to make
AAT seem even half way believable, you should propose that humans lost their fur
recently, after leaving the water.
Lorenzo
Sherilyn
>And unless I see Marc
>significantly falter, this is my last posting on the
>subject. He is doing an excellent job, far better than
>I can on the great majority of issues.
Do you think Marc will be able to explain why the AAT should predict
that intelligent spacetravelling aliens will tend to have a humanoid
shape? This is the substance of your claim, is it not?
--
Sherilyn
Grad Student, University of Ediacara
Following this thread from talk.origins
PZ Myers
<Sher...@sidaway.demon.co.uk> wrote:
>In article <6u7rc1$8ko$1...@nnrp1.dejanews.com>, myke_r...@yahoo.com
>writes
>>Sherilyn <Sher...@sidaway.demon.co.uk> wrote:
>>> my...@netaxs.com (PZ Myers) wrote:
>>> > Of course. You don't know Michael very well if you don't yet realize that
>>> > every piece of evidence somehow supports his argument.
>>>
>>> Being a self-proclaimed genius scientist and mass murderer isn't easy;
>>> he has to economize with the evidence.
>>
>>Mass murderer...? Now there is a salient rebuttal if I've ever
>>seen one!
>
>Michael, go to a dictionary and look up the meaning and usage of the
>word _salient_. The account of mass murder is your own, by the way.
It is, apparently, his favorite word right now. He seems to be trying to
plug it into just about every paragraph, appropriate or not.
>
>
>[excerpt from a long post]
>...
> "The most dramatic experience was when I was 12, and as
> a result of puberty, I was able to break free and had my run
> of the ship. I went on a killing spree and managed to make
> my way to the incubatory room with the fetuses. The fish
> tanks the alien hybrid fetuses were in were solidly
> mounted, but the lids could be opened, so I started
> pulling them out and breaking their necks. If you know
> anything about the alien attitude toward these hybrid
> fetuses, you'd immediately understand my motivation
> here. It's a bit much to describe here, but I'm most
> certain not a homicidal maniac under any other
> conditions.
> ...
> At the time, the only other thing I noticed was that,
> when visiting my girlfriend and petting her pet
> rabbit, I found myself cognating on the fact that
> the rabbit's neck was so thin I could break it in
> a moment. I have always had a fondness for
> animals and had many pets myself. The feeling
> was not overpowering, but it was clear and
> distinct and left me feeling very disquieted and
> utterly perplexed."
Breaking the necks of alien hybrid fetuses in fish tanks? I knew
this guy had to be a total loon, and that sort of confirms it.
The real clincher, though, is his misuse of the word "cognate" as
a verb (oh, the horror!), in a context that suggest he doesn't know what
it means anyway. I suppose it is possible that somebody on such intimate
terms with the breeding practices of alien beings might know of some way
to acquire a blood relationship with a rabbit (or with a rabbit's neck?
With a fact? I'm confused), but it is beyond my capacity to imagine,
I'm afraid.
Of one thing I'm certain: keep him away from me when he is in a 'cognating'
mood.
--
PZ Myers
Lorenzo L. Love
PZ Myers wrote:
> Breaking the necks of alien hybrid fetuses in fish tanks? I knew
> this guy had to be a total loon, and that sort of confirms it.
>
Hey, I saw that on The X-Files so it must be true.
Lorenzo
myke_r...@yahoo.com
> myke_r...@yahoo.com writes
> ...
> >And unless I see Marc
> >significantly falter, this is my last posting on the
> >subject. He is doing an excellent job, far better than
> >I can on the great majority of issues.
>
> Do you think Marc will be able to explain why the AAT should predict
> that intelligent spacetravelling aliens will tend to have a humanoid
> shape? This is the substance of your claim, is it not?
As I have stated repeatedly, I have never brought up such a discussion
on this forum. I have argued exclusively for the validity of AAT on
this forum. You attempt to bring it up only as a diversion from your
failure to saliently address the arguments for AAT. The conjecture was
merely with regards to possible paths of evolution on other life
bearing planets, not with regards to "spacetravelling aliens" [sic].
It is not an appropriate topic for debate on SAP unless AAT were
firmly accepted.
Now you have even gone so far as to attempt to change the discussion
to abduction. I'm quite certain that no one on SAP is interested in
hearing about this topic. The only thing I will say on this matter is
that, even if the experiences are real, destroying clones is like
throwing away a computer, not murder. The only reason I brought it up,
even on alt.alien.visitors, was in reference to the sudden onset of
severe heart problems that I experienced at the age of 12. But you
snipped that in order to take the comments out of context. You bring
it up only as a means of personal attack, since you have proven unable
to engage in salient debate. It is no more relevant to the topic than
excruciating details about your sex life as a transvestite, or your
endless references to your wearing of panties.
I'm quite certain that no one on this forum appreciates these
superfluous topics being brought up on a forum for which it has
no relevance. You harm your own credibility as much as mine by
engaging in these tactics, and I'm sure that the readers of SAP would
like to see you gone just as much as me at this point. You are a
liability to cogent scientific debate on SAP.
Unless a criticism of AAT is directed at me, I will not answer on this
forum, and I will certainly not answer attempts to change the subject
to topics relevant only to alt.alien.visitors, which Mr. Sherilyn has so
thoughtfully decided to bring to SAP, along with starting a discussion
by cross posting to alt.alien.visitors in it's original post about AAT.
Elaine Morgan
<Sher...@sidaway.demon.co.uk> writes
>> mating [is a ] key feature of AAT
>...
>Have bonoboes ever undergone aquatic adaptation? They often
>mate belly-to-belly, and are believed to be our closest living
>relatives.
>Sherilyn
It is arguable that they underwent the first stages - i.e. wading
behaviour, leading to frequent functional bipedal locomotion; but that
the water in their swamp forest was never deep or clean enough to
result in diving. So they would not have lost their fur, nor acquired
breathing modifications. The interesting thing is that they are not
genetically our closest relatives - no closer than the common chimp.None
of the acres of print about them has suggested (or as far as I know even
sought) a reason why they resemble us more closely than Pan troglodytes.
Except those who have glanced, a little nervously, at the water throey.
Elaine
>
--
myke_r...@yahoo.com
> myke_r...@yahoo.com wrote:
> You've also dodged my criticism. The adaptations that marine mammals
> exhibit tend to compromise the ability of the pelvis and hindlimbs to
> support bipedal locomotion.
The word "tend" is critical here. Your objection does not "tend" to
apply to creatures other than quadrupeds. You are making inappropriate
comparisons between features unique to quadrupeds that could never
become bipedal, and other animals. They evolved the way they did because
they had to rapidly give up on all but the most minimal terrestrial
locomotion as a result of being denied any avenue to bipedalism.
Penguins, for example, have not suffered significantly more than
humans in this regard precisely because they were not denied this
avenue, just as primates are not.
> Also, given your kind of thinking here, if the "selective pressures"
> to free up and use the forelimbs are so great, why can't they also
> drive modifications to terrestrial primates?
You've put the cart before the horse. The fact is that prehensile
fingers alone clearly do not create strong selective pressures for
linear symmetry, but marine adaptation does. This fact is beyond
contention. Once this transition is made, primates are unique
in having their options still very open. Once this transition is
made in quadrupeds, they have no such options available, they
have no advantage what-so-ever to be gained from bipedalism.
You have falsely asserted that the argument is that prehensile
fingers cause the advent of linear symmetry. What it in fact
does is leave the options wide open for such an animal. An animal
with prehensile fingers does have a potential advantage from
bipedalism, where as quadrupeds have none. If you differ with
this argument, then you must either demonstrate how primates
could not be advantaged by bipedalism, or how quadrupeds could
potentially be benefited by bipedalism. You have done neither.
> They also tend to promote some characteristic anatomical changes
> that we simply do not have.
Your criticism is based on a false assertion of AAT. You seem to
think that if AAT predicts that similar selective pressures are
in place, that AAT must assert that they must be present in
IDENTICAL proportions. This is a false expression of AAT. You
are not countering AAT, but some distorted facsimile of AAT
of your own invention. AAT postulates that similar selective
pressures are in place, but it does not in any way postulate
that they are present with the same force relative to one
another. Quite to the contrary. Your criticism is based on
making this false assumption, which is not in any way a part
of AAT.
> Conjuring up putative "selective pressures" that drive this
> hypothetical marine ancestor to rear up on two legs on land doesn't
> work -- evolution isn't simply about automatically acquiring whatever
> traits we think look desirable, organisms have to live with the
> limitations and potential of their ancestry.
Evolution is quite simply about acquiring desirable traits. Your
distinction between looking desirable and being desirable is purely
semantic. If it is desirable, i.e. superior, then it is selected
for, period. If we can't tell that it is a superior trait by
"looking", how does one tell?... And the selective pressures
in question are absolute, not putative. Name a single marine
mammal without linear symmetry? Name a single other terrestrial
animal besides humans and penguins with linear symmetry? If you
can name no counter examples, then the process in question is
absolute so far as can be determined currently and not in any way
potentially reputed by current evidence.
> Oy. I've been wasting my time arguing with a lunatic.
And I appear to be wasting my time with someone who could
not address the argument in anything other than the most
facile fashion, even if his life depended on it. Instead,
of addressing the argument in a coherent fashion, you
substitute personal attacks. Oy, indeed. You and your
trans-sexual friends are something else. People who live
in glass houses...
Sherilyn
>
...
> > In short:
> > - Furlessness is seen in all fully aquatics, all very large aquatics, some
> > tropical mammals (pachyderms, babirusa, naked molerat, naked bat),
> > domesticated dog & pig.
> > - Aquatics are only furless if they are very big, if they are fully aquatic,
> > & in some tropical ones (hippo, babirusa).
> > - All semi-aquatics are furred except the very big ones (male Steller
> > sealion, walrus, elephant seal) & except a few tropical semi-aquatics (eg,
> > hippo, babirusa).
> > - Some tropical mammals that sleep in holes are sparsely haired (aardvark,
> > hunting-dog, warthog).
> > Conclusion: our furlessness does of course not prove that humans spent a lot
> > of time in the water, but it's a strong argument. It also strongly suggests
> > that our ancestors were (sub)tropical - but that's no news.
> >
> > Marc
>
> How can it be a strong argument for aquaticism when the very reasons you list
> argue against any hairless mammal below 50 kg being aquatic? If you want to
> make AAT seem even half way believable, you should propose that humans lost
> their fur recently, after leaving the water.
I find this spectacle of feature-shopping quite sad, given the source.
If one is going to pick and choose observations from a list of features
that all aquatics have in common in this manner and present the results as
"strong evidence" for an aquatic phase in human ancestry, why stop there?
Maybe all Capricorns are intelligent, sensitive, with a talent for music,
except those with one of the inner planets transiting their natal moon,
who knows? And if we find someone who doesn't fit that rule, why, we can
always make up another exception.
--
Sherilyn
Elaine Morgan
<Sher...@sidaway.demon.co.uk> writes
>In article <6tuh9r$mur$1...@xenon.inbe.net>,
> "Marc Verhaegen" <Marc.Ve...@village.uunet.be> wrote:
>>
>> Sherilyn heeft geschreven in bericht <6trodj$l46$1...@nnrp1.dejanews.com>...
>>
>[Michael wrote]
>> >>1) If human beings are not semi-aquatic, then primate is the only order
>> >>of mammal without an aquatic member.
>> >>
>> Exaggeration.
>
>Agreed. Michael's argument was an exaggeration.
Could you name the other Orders without an aquatic member please? You
may be right but nothing springs to mind...
Elaine
Elaine Morgan
<mat...@ix.netcom.com> writes
>
>Rhinos and elephants have less hair than most mammals. Therefore
>rhinos and elephants evolved in the ocean. Otters and seals and sea
>lions have dense fir. Therefore they are not aquatic. Do I have this
>right?
>
Oh, come on. Most mammals are covered with hair. The exceptions are so
rare that anyone with a smidgin of scientific curiosity wonders what
made them exceptional. Cut out Somalia, and you have the proposition
that it had something to do with water, because all the hairless ones
have not only hairlessness but a cluster of other shared
characteristics. About 90 per cent are either aquatic or semi aquatic,
or belong to species which there are other reputable reasons to suspect
had aquatic or semiaquatic ancestors.
Your phoney syllogism is like saying: Most polar mammals have white or
seasonally white pelts. The walrus does not, therefore it must live in
the tropics.
Elaine Morgan
Sherilyn
my...@netaxs.com (PZ Myers) wrote:
> In article <kTzjrJAJ...@sidaway.demon.co.uk>, Sherilyn
> <Sher...@sidaway.demon.co.uk> wrote:
> > ...The fish
> > tanks the alien hybrid fetuses were in were solidly
> > mounted, but the lids could be opened, so I started
> > pulling them out and breaking their necks. If you know
> > anything about the alien attitude toward these hybrid
> > fetuses, you'd immediately understand my motivation
> > here. It's a bit much to describe here, but I'm most
> > certain not a homicidal maniac under any other
> > conditions.
> > ...
> > the rabbit's neck was so thin I could break it in
...>
> Breaking the necks of alien hybrid fetuses in fish tanks? I knew
> this guy had to be a total loon, and that sort of confirms it.
>
> I suppose it is possible that somebody on such intimate
> terms with the breeding practices of alien beings might know of some way
> to acquire a blood relationship with a rabbit (or with a rabbit's neck?
> With a fact? I'm confused), but it is beyond my capacity to imagine,
> I'm afraid.
Well in a loose sense, rabbits and humans are cognate. I guess that
explains why we share some salient features: live birth, lactation,
high body temperature, fast metabolism, hairy skin, etc.
>
> Of one thing I'm certain: keep him away from me when he is in a 'cognating'
> mood.
...
I think it's a shame he had to rush off before he was able to resume
discussion of his claims rather than pushing that straw man claim of his
that I had to to refute the AAT. I should have quite enjoyed discussing his
ideas about applying the AAT to exobiology.
Matt Silberstein
<Marc.Ve...@village.uunet.be>:
>
>Sherilyn heeft geschreven in bericht <6tv4jr$ar1$1...@nnrp1.dejanews.com>...
>
[snip]
>>There's no law of nature that says things have to turn out a certain way.
>
>If you are a mammal & you're adapting to aquatic life, at some point, you
>will loose your fur, because all fully aquatics are furless. So we can say:
>if you are fully aquatic, you "must" have lost your fur.
>
Are you really suggesting that H.S. was, at some time in evolutionary
history, fully aquatic? That is, that H.S. (or its evolutionary
precursors) lived entirely in the water and not on land? Are there any
such mammals that kept separate legs?
[snip]
Matt Silberstein
-----------------------------
"Well, art is art, isn't it? Still, on the other hand, water is water!
And east is east, and west is west, and if you take cranberries and stew them
like applesauce they taste much more like prunes than rhubarb does.
Now, uh.....Now you tell me what you know."
Julius Marx
Matt Silberstein
<Sher...@sidaway.demon.co.uk>:
[snip]
>
>Being a self-proclaimed genius scientist and mass murderer isn't easy;
>he has to economize with the evidence.
Is there a reason for the "mass murderer" comment?