why did we lose our fur?
kyr...@gmail.com
marsupial has lost their hair.
Inez
kyrc...@gmail.com wrote:
> Why did humans out-evolve fur and hair? Almost no other mammal or
> marsupial has lost their hair.
Check the top of your head. If you can't find any there, I can give
you more hints, but you'll want a private place to make your
examination.
Pip R. Lagenta
>Why did humans out-evolve fur and hair? Almost no other mammal or
>marsupial has lost their hair.
Watch this film and write a report:
<http://www.nhm.ac.uk/visit-us/galleries/darwin-centre//live/qt/120604ChristopheSoligohi.html>
HTH
`
--
內躬偕爻,虜,齯滌`偕爻,虜,齯滌`偕爻,虜,齯滌`偕爻,虜,齯滌`偕爻,
Pip R. Lagenta Pip R. Lagenta Pip R. Lagenta Pip R. Lagenta
�虜,齯滌`偕爻,虜,齯滌`偕爻,虜,齯滌`偕爻,虜,齯滌`偕爻,虜,齯滌
-- Pip R. Lagenta
President for Life
International Organization Of People Named Pip R. Lagenta
(If your name is Pip R. Lagenta, ask about our dues!)
<http://home.comcast.net/~galentripp/pip.html>
(For Email: I'm at home, not work.)
Ye Old One
<morbiu...@comcast.net> enriched this group when s/he wrote:
>On 27 Jan 2006 16:01:21 -0800, kyr...@gmail.com wrote:
>>Why did humans out-evolve fur and hair? Almost no other mammal or
>>marsupial has lost their hair.
>
>Watch this film and write a report:
><http://www.nhm.ac.uk/visit-us/galleries/darwin-centre//live/qt/120604ChristopheSoligohi.html>
>HTH
>`
good find.
--
Bob.
Dana Tweedy
<kyr...@gmail.com> wrote in message
news:1138406481....@o13g2000cwo.googlegroups.com...
> Why did humans out-evolve fur and hair? Almost no other mammal or
> marsupial has lost their hair.
Maybe we forgot our receipt at the furriers?
DJT
>
Friar Broccoli
kyr...@gmail.com wrote:
> Why did humans out-evolve fur and hair? Almost no other mammal or
> marsupial has lost their hair.
I didn't watch the suggested film because unnecessary plugins
are works of the devil.
I have heard it was for heat loss to provide better endurance when
chasing
prey. Muscles work better when they can get rid of heat faster.
Also easier to keep parasites off.
Cordially;
Friar Broccoli
Robert Keith Elias, Quebec, Canada Email: EliasRK (of) gmail * com
Best programmer's & all purpose text editor: http://www.semware.com
--------- I consider ALL arguments in support of my views ---------
Scott
> marsupial has lost their hair.
all savanna mammals have a muzzle to dissipate body heat except one, humans.
Jenny6833A
Marc
Too much information!
<grin>
(signed) marc
M. Buhler
Parramatta
Oh - and "Happy Year of the Dog"
.
NashtOn
Did you miss the part where he asked about fur? Are you going to brush
off the question and ridicule the OP even further?
I don't think evolutionary "science" has any answers to these questions,
just as they have no answers for sex, chirality and abiogenesis vs
divine creation.This advocacy forum for the ToE is not a place to ask
these types of questions, otherwise the goons that take for the
evolution team will chew you to pieces and spit you out.
--
Nicolas
"The reason the theory of evolution is so controversial is that it is
the main scientific prop for scientific naturalism. Students first learn
that "evolution is a fact," and then they gradually learn more and more
about what that "fact" means. It means that all living things are the
product of mindless material forces such as chemical laws, natural
selection, and random variation. So God is totally out of the picture,
and humans (like everything else) are the accidental product of a
purposeless universe. Do you wonder why a lot of people suspect that
these claims go far beyond the available evidence?" Phillip E.Johnson,
The Church Of Darwin
John Wilkins
--
John S. Wilkins, Postdoctoral Research Fellow, Biohumanities Project
University of Queensland - Blog: evolvethought.blogspot.com
Servum tui ero, ipse vespera
Ye Old One
group when s/he wrote:
>Inez wrote:
>> kyrc...@gmail.com wrote:
>>
>>>Why did humans out-evolve fur and hair? Almost no other mammal or
>>>marsupial has lost their hair.
>>
>>
>> Check the top of your head. If you can't find any there, I can give
>> you more hints, but you'll want a private place to make your
>> examination.
>>
>
>Did you miss the part where he asked about fur? Are you going to brush
>off the question and ridicule the OP even further?
>
>I don't think evolutionary "science" has any answers to these questions,
>just as they have no answers for sex, chirality and abiogenesis vs
>divine creation.This advocacy forum for the ToE is not a place to ask
>these types of questions, otherwise the goons that take for the
>evolution team will chew you to pieces and spit you out.
Try looking at the video Pip linked to - it gives three different
possible reasons for reduced hair - as well as pointing out that we do
in fact have as many hairs as other great apes.
--
Bob.
Friar Broccoli
> Did you miss the part where he asked about fur? Are you going
> to brush off the question and ridicule the OP even further?
> I don't think evolutionary "science" has any answers to these
> questions, just as they have no answers for sex, chirality and
> abiogenesis vs divine creation.
I agree that chirality is not understood nor abiogenesis
(assuming it occurred). However, I am not aware of any particular
problem with bisexual reproduction. What part of it do you
believe is not understood?
Also I am curious about why you think chirality might support ID
or creation. To me it just looks like another one of those dumb
"choices" made by evolution. Why would a designer have cared
about molecular handedness?
Inez
NashtOn wrote:
> Inez wrote:
> > kyrc...@gmail.com wrote:
> >
> >>Why did humans out-evolve fur and hair? Almost no other mammal or
> >>marsupial has lost their hair.
> >
> >
> > Check the top of your head. If you can't find any there, I can give
> > you more hints, but you'll want a private place to make your
> > examination.
> >
>
> Did you miss the part where he asked about fur?
He said "fur and hair." I am more expert in the hair part, so I did
what I could.
> Are you going to brush
> off the question and ridicule the OP even further?
>
We'll not be to the brushing stage until he locates his hair. I shall
leave the ridicule to you, I prefer good natured kidding myself.
> I don't think evolutionary "science" has any answers to these questions,
> just as they have no answers for sex, chirality and abiogenesis vs
> divine creation.
Yes, well, you're not exactly open to learning the answers in any
event. This would seem less tragic if you were happier in your
ignorance.
>This advocacy forum for the ToE is not a place to ask
> these types of questions, otherwise the goons that take for the
> evolution team will chew you to pieces and spit you out.
>
Or worse yet, tell you things you prefer not to believe.
Inez
Friar Broccoli wrote:
> NashtOn wrote:
>
> > Did you miss the part where he asked about fur? Are you going
> > to brush off the question and ridicule the OP even further?
>
> > I don't think evolutionary "science" has any answers to these
> > questions, just as they have no answers for sex, chirality and
> > abiogenesis vs divine creation.
>
> I agree that chirality is not understood nor abiogenesis
> (assuming it occurred). However, I am not aware of any particular
> problem with bisexual reproduction. What part of it do you
> believe is not understood?
>
line like that...
>of my views ---------
Nick Keighley
> >>Why did humans out-evolve fur and hair? Almost no other mammal or
> >>marsupial has lost their hair.
> >
> > Check the top of your head. If you can't find any there, I can give
> > you more hints, but you'll want a private place to make your
> > examination.
>
> Did you miss the part where he asked about fur? Are you going to brush
> off the question and ridicule the OP even further?
and your definition of the difference between hair and fur is?
> I don't think evolutionary "science" has any answers to these questions,
> just as they have no answers for sex,
sex is a handy method for mixing and matching genes. Even bacteria
exchange genes.
> chirality
does it need one. Early life selected one way and everything else
followed.
So why did god fix chirality?
> and abiogenesis vs divine creation.
I think you've been told this before, but I'll remind you. Evolution
and
abiogenesis are separate subjects
> This advocacy forum for the ToE is not a place to ask
> these types of questions,
there are well in formed people here, so its not a bad place
> otherwise the goons that take for the
> evolution team will chew you to pieces and spit you out.
come back Eccles all is forgiven
--
Nick Keighley
Chris Thompson
news:kbJCf.2670$VV4....@ursa-nb00s0.nbnet.nb.ca:
> Inez wrote:
>> kyrc...@gmail.com wrote:
>>
>>>Why did humans out-evolve fur and hair? Almost no other mammal or
>>>marsupial has lost their hair.
>>
>>
>> Check the top of your head. If you can't find any there, I can give
>> you more hints, but you'll want a private place to make your
>> examination.
>>
>
> Did you miss the part where he asked about fur? Are you going to brush
> off the question and ridicule the OP even further?
Tell me the difference between fur and hair, Nashy.
Chris
er...@swva.net
> NashtOn wrote:
> > Inez wrote:
> > > kyrc...@gmail.com wrote:
>
> > >>Why did humans out-evolve fur and hair? Almost no other mammal or
> > >>marsupial has lost their hair.
> > >
> > > Check the top of your head. If you can't find any there, I can give
> > > you more hints, but you'll want a private place to make your
> > > examination.
> >
> > Did you miss the part where he asked about fur? Are you going to brush
> > off the question and ridicule the OP even further?
>
> and your definition of the difference between hair and fur is?
>
I don't know a scientific or even a general-dialect definition of
either one, but was once told with respect to dog coats, that it's
"fur" if it sheds out with the season and never needs cutting, and
"hair" if it keeps growing unless cut.
>
> > I don't think evolutionary "science" has any answers to these questions,
> > just as they have no answers for sex,
>
Yeah, but the explanations are better and more consistent than the
alternatives, and refusing to advocate any explanation (a la Glenn and
NashtOn) totally flunks.
> sex is a handy method for mixing and matching genes. Even bacteria
> exchange genes.
>
> > chirality
The answer may show up someday in some other discipline, such as
physics or chemistry.
>
> does it need one. Early life selected one way and everything else
> followed.
> So why did god fix chirality?
>
>
> > and abiogenesis vs divine creation.
If we ever get evidence of divine creation, we can worry about that
then. In the meantime, it's total surrender to wishful thinking to
think that such evidence will point to one's own preferred deity, and
bolster one's own preferred mode of worship.
>
> I think you've been told this before, but I'll remind you. Evolution
> and
> abiogenesis are separate subjects
>
>
> > This advocacy forum for the ToE is not a place to ask
> > these types of questions,
Says you.
>
> there are well in formed people here, so its not a bad place
>
>
> > otherwise the goons that take for the
> > evolution team will chew you to pieces and spit you out.
Which is only even doable in the case when you come in here spouting a
bunch of rubbish.
>
> come back Eccles all is forgiven
>
> --
> Nick Keighley
Eric Root
Richard Smol
kyr...@gmail.com wrote:
> Why did humans out-evolve fur and hair? Almost no other mammal or
> marsupial has lost their hair.
They didn't. Human beings still have fur, it's just a lot shorter... at
least with most people ;)
RS
Don Cates
wrote:
>Jenny6833A wrote:
>> kyr...@gmail.com wrote:
>>
>>> Why did humans out-evolve fur and hair?
>>
>> You haven't met my husband.
>>
>> :-)
>>
>> Jenny
>>
>Or me...
>
Lucky my body was there to catch the hair that fell off my head!
(The chest wax scene in _The 40 Year Old Virgin_ was !real!)
--
Don Cates ("he's a cunning rascal" - PN)
rev.goetz
kyr...@gmail.com wrote:
> Why did humans out-evolve fur and hair? Almost no other mammal or
> marsupial has lost their hair.
Charles Darwin wrote _The_ _Descent_ _of_ _Man,_ _and_ _Selection_ _in_
_Relation_ _to_ _Sex._ Perhaps there are ideas from this book that
could possibly explain how selection favored the loss of fur during
human evolution.
r norman
wrote:
There have been one or two papers written in biology since that time.
A currently fashionable hypothesis for the present relates to
parasitism.
M. Pagel and W. Bodmer
A naked ape would have fewer parasites
Proc Biol Sci. 2003 Aug 7;270 Suppl 1:S117-9.
rev.goetz
Perhaps parasitism, but perhaps also the loss of fur was fashionable.
rev.goetz
How come this did not converge on all populations of apes?
r norman
wrote:
>
>r norman wrote:
>> On 28 Jan 2006 14:28:41 -0800, "rev.goetz" <jimgo...@yahoo.com>
>> wrote:
>>
>> >
>> >kyr...@gmail.com wrote:
>> >> Why did humans out-evolve fur and hair? Almost no other mammal or
>> >> marsupial has lost their hair.
>> >
>> >Charles Darwin wrote _The_ _Descent_ _of_ _Man,_ _and_ _Selection_ _in_
>> >_Relatio"We suggest that hairlessness is maintained by these naturally selected benefits and by sexual selection operating on both sexes.n_ _to_ _Sex._ Perhaps there are ideas from this book that
>> >could possibly explain how selection favored the loss of fur during
>> >human evolution.
>>
>> There have been one or two papers written in biology since that time.
>> A currently fashionable hypothesis for the present relates to
>> parasitism.
>> M. Pagel and W. Bodmer
>> A naked ape would have fewer parasites
>> Proc Biol Sci. 2003 Aug 7;270 Suppl 1:S117-9.
>>
>> http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12952654&dopt=Abstract
>
>Perhaps parasitism, but perhaps also the loss of fur was fashionable.
It isn't my hypothesis, but the abstract I cited says "We suggest that
hairlessness is maintained by these naturally selected benefits and by
sexual selection operating on both sexes."
Things don't always have to have a single reason.
r norman
wrote:
It isn't my hypothesis, but that abstract I cited says: "Hairlessness
is made possible in humans owing to their unique abilities to regulate
their environment via fire, shelter and clothing. Clothes and shelters
allow a more flexible response to the external environment than a
permanent layer of fur and can be changed or cleaned if infested with
parasites. "
wf...@comcast.net
>Inez wrote:
>> kyrc...@gmail.com wrote:
>>
>>>Why did humans out-evolve fur and hair? Almost no other mammal or
>>>marsupial has lost their hair.
>>
>>
>> Check the top of your head. If you can't find any there, I can give
>> you more hints, but you'll want a private place to make your
>> examination.
>>
>
>Did you miss the part where he asked about fur? Are you going to brush
>off the question and ridicule the OP even further?
>
>I don't think evolutionary "science" has any answers to these questions,
>just as they have no answers for sex, chirality and abiogenesis vs
>divine creation.T
gee. biology has no cure for the common cold
i guess viruses don't exist...
Friar Broccoli
Evolution selects for those CHANCE adaptations which best suite a
species
to its LOCAL/CURRENT environment/conditions. Ie. not all apes had the
same opportunities.
Mark Isaak
>Why did humans out-evolve fur and hair?
We gave it up for Lint.
--
Mark Isaak eciton (at) earthlink (dot) net
"Voice or no voice, the people can always be brought to the bidding of
the leaders. That is easy. All you have to do is tell them they are
being attacked, and denounce the pacifists for lack of patriotism and
exposing the country to danger." -- Hermann Goering
NashtOn
> NashtOn wrote:
>
>
>>Did you miss the part where he asked about fur? Are you going
>>to brush off the question and ridicule the OP even further?
>
>
>>I don't think evolutionary "science" has any answers to these
>>questions, just as they have no answers for sex, chirality and
>>abiogenesis vs divine creation.
>
>
> I agree that chirality is not understood nor abiogenesis
> (assuming it occurred).
Okay, so far.
However, I am not aware of any particular
> problem with bisexual reproduction. What part of it do you
> believe is not understood?
Why did *nature* select for sexual reproduction vs asexual.
>
> Also I am curious about why you think chirality might support ID
> or creation. To me it just looks like another one of those dumb
> "choices" made by evolution. Why would a designer have cared
> about molecular handedness?
The question one must ask oneself is not why a designer would have
cared, but what purpose and function does it serve in *evolution*.
Pas bete comme question, hein?
>
> Cordially;
>
> Friar Broccoli
> Robert Keith Elias, Quebec, Canada Email: EliasRK (of) gmail * com
> Best programmer's & all purpose text editor: http://www.semware.com
>
> --------- I consider ALL arguments in support of my views ---------
>
Friar Broccoli
>
> Why did *nature* select for sexual reproduction vs asexual.
>
[ concerning chirality]
>
> The question one must ask oneself is not why a designer would have
> cared, but what purpose and function does it serve in *evolution*.
> Pas bete comme question, hein?
Thanks for responding.
There are clear and fairly simple answers to both your questions.
It will take me a bit of time to produce clear explanations.
My answers should be ready by noon tomorrow.
Hopefully they will be both short and clear.
Thank you again for replying;
John Wilkins
> On Sat, 28 Jan 2006 22:57:34 +1000, John Wilkins <jo...@wilkins.id.au>
> wrote:
>
>> Jenny6833A wrote:
>>> kyr...@gmail.com wrote:
>>>
>>>> Why did humans out-evolve fur and hair?
>>> You haven't met my husband.
>>>
>>> :-)
>>>
>>> Jenny
>>>
>> Or me...
>>
> Lucky my body was there to catch the hair that fell off my head!
> (The chest wax scene in _The 40 Year Old Virgin_ was !real!)
My chest and back sucked the hair off my head. Then redistributed some to my
ears and nose.
John Wilkins
> On 27 Jan 2006 16:01:21 -0800, kyr...@gmail.com wrote:
>
>> Why did humans out-evolve fur and hair?
>
> We gave it up for Lint.
>
Chris H. Fleming
> Friar Broccoli wrote:
> > NashtOn wrote:
> >
> >
> >>Did you miss the part where he asked about fur? Are you going
> >>to brush off the question and ridicule the OP even further?
> >
> >
> >>I don't think evolutionary "science" has any answers to these
> >>questions, just as they have no answers for sex, chirality and
> >>abiogenesis vs divine creation.
> >
> >
> > I agree that chirality is not understood nor abiogenesis
> > (assuming it occurred).
>
> Okay, so far.
>
> However, I am not aware of any particular
> > problem with bisexual reproduction. What part of it do you
> > believe is not understood?
>
> Why did *nature* select for sexual reproduction vs asexual.
My guess is genetic diversity.
z
>Inez wrote:
>> kyrc...@gmail.com wrote:
>>
>>>Why did humans out-evolve fur and hair? Almost no other mammal or
>>>marsupial has lost their hair.
>>
>>
>> Check the top of your head. If you can't find any there, I can give
>> you more hints, but you'll want a private place to make your
>> examination.
>>
>
>Did you miss the part where he asked about fur? Are you going to brush
>off the question and ridicule the OP even further?
>
>I don't think evolutionary "science" has any answers to these questions,
>just as they have no answers for sex, chirality and abiogenesis vs
>divine creation.This advocacy forum for the ToE is not a place to ask
>these types of questions, otherwise the goons that take for the
>evolution team will chew you to pieces and spit you out.
Lanugo.
Chirality is a chemistry question- while there is certainly a bias for
one chirality for biolmolecules, the choice of handedness is different
for sugars and amino acids. Absentminded designer, or random chance?
To forstall the idiot question, yes both enantioners of amino acids
and sugars are equally reactive.
Sex? It's fun, and also reassorts the genome. Bacteria tend towards
scavenger hunt sex, so why seperate sexes evolved is still an open
area of research. Bdelloid rotifers seem to being doing fine in the
apprent absence of sex. Personally, I think we are missing something
in the macronucleus-micronucleus conversion.
B Miller
Nicholas
> NashtOn wrote:
>>>problem with bisexual reproduction. What part of it do you
>>>believe is not understood?
>>
>>Why did *nature* select for sexual reproduction vs asexual.
>
> My guess is genetic diversity.
This is one of the interesting questions. We know that sexual
reproduction helps diveristy and adaptation, but that is in hindsight.
We know that sexual reproduction has a much higher cost than asexual
reproduction. So given that evolution has no goals, what was it that
drove the move to sexual reproduction in the first place? To me genetic
diversity isn't a good answer as the orginal population would have been
asexual and hence wouldn't have derived much benefit from sex on that basis.
Obviously gene swapping is useful (bacteria do it despite being asexual)
but why do it via sex? And why have male and female? Hermaphrodite
reproduction ensures sexual reproduction and that each individual
produces children, not just half.
I can see why sex became so popular once it arrived, I just don't find
any of the existing explanations (or at least the ones I'm aware of) as
to how it came to be in the first place that convincing.
Nicholas
Jesus H Christ
> Inez wrote:
>> kyrc...@gmail.com wrote:
>>
>>>Why did humans out-evolve fur and hair? Almost no other mammal or
>>>marsupial has lost their hair.
>>
>>
>> Check the top of your head. If you can't find any there, I can give
>> you more hints, but you'll want a private place to make your
>> examination.
>>
>
> Did you miss the part where he asked about fur? Are you going to brush
> off the question and ridicule the OP even further?
YOU ASSCLOWN, HE'S POINTING OUT WE HAVEN'T LOST OUR FUR.
Are you fucking retarded or do you just pretend to be one on USENET?
We *have* fur. We choose to call it 'hair'.
> I don't think evolutionary "science" has any answers to these
> questions,
Actually, there is some very good research on just this topic.
There are promising avenues of investigation revolving around extended
activity on the african savannah during daytime along with intelligence
to provide better nesting during cold nights. This fits humans
excellent evolved heat-coping and long-duration endurance abilities.
Run 'em down, kill them with smarts rather than brawn, get take-away and
sleep snug. It's good to be a human.
> just as they have no answers for sex,
For fucks sake [that's a pun, kids], this is a no-brainer.
Sex is a means of increasing genetic diversity in a population to
increase the speed at which genes can be selected for.
> chirality
Another simple one. Positive feedback and chance.
There ARE suggestions rooted in quantum Physics, but the most promising
answers revolve around mathematical analysis of positive feedback
systems in the organic chemistry of self-reproducing chemicals - such as
RNA.
Basically, if a population has a tendency to select one option
increasingly as that population increases as a ratio, then it will tend
to converge rapidly.
> and abiogenesis vs
> divine creation.
Sorry, don't have a scientific answer for that one yet. The
materialistic answer is "well, it sure as shit ain't god".
The best answer seems to be proto-RNA in cellular-like encapsulating
environments, then protocells (using self-assembling lipids), then cells
(with the cell walls produced as part of the self-reproducing system).
But since science is working on it, so keep that thought in mind.
We'll have an answer for you in a few decades or so.
> This advocacy forum for the ToE is not a place to ask
> these types of questions, otherwise the goons that take for the
> evolution team will chew you to pieces and spit you out.
Yup. We have the facts, the theories to cover the facts and the
intelligence to muster both of them - and all you have is your pathetic
little banner with the word 'faith' scribbled on it in crayon.
Sucks to be you, hey?
WASH MY FEET, FUNDIE!
JEEEEEEEEEEEEEEEESUS!
Martin Hutton
In the "navel gazing" category:
> >Why did humans out-evolve fur and hair?
>
> We gave it up for Lint.
--
Martin Hutton
"The truths of religion are never so well understood as
by those who have lost the power of reasoning."
...Voltaire, "Philosophical Dictionary" 1764
Dan Luke
"Martin Hutton" wrote:
> In the "navel gazing" category:
>
>> >Why did humans out-evolve fur and hair?
>>
>> We gave it up for Lint.
Haw-haw!
Seconded.
Friar Broccoli
In what follows I have reversed the order of the questions. I
put sexual reproduction last because I make a point concerning
design in the discussion of chirality that I follow up in the
discussion of sexual reproduction.
Sorry about the length, and also I am sure the writing could be
better. By trying (and failing) to meet my deadline I wrote
this in under 4 hours, and I am sure at least another 2 are
needed.
NashtOn wrote:
> Friar Broccoli wrote:
>> NashtOn wrote:
[... snipping to get to the point ...]
>>> I don't think evolutionary "science" has any answers to
>>> these questions, just as they have no answers for sex,
>>> chirality and abiogenesis vs divine creation.
[... order changed ...]
>> ... I am curious about why you think chirality might support
>> ID or creation. To me it just looks like another one of
>> those dumb "choices" made by evolution. Why would a designer
>> have cared about molecular handedness?
> The question one must ask oneself is not why a designer would
> have cared, but what purpose and function does it serve in
> *evolution*.
Essentially all of the living things we see around us today are
constructed from 20 simple building blocks, the amino acids. The
amino acids can be considered as nothing more than Lego Blocks,
which DNA and RNA use to assemble cells and organs (which are
mostly just groups of cells).
Organisms use these 20 amino acids because they can be fitted
together to make reliable copies of everything they need to
build. If an organism changed the shape (the molecular
structure) of one of its amino acids, it would no longer be able
to make good copies of itself. In exactly the same way, you
cannot built something from lego blocks if half the blocks are
of a different design. They just won't fit together.
Right handed chirality is one aspect of the shape of 19 of the
amino acids. When they all have the same chirality they fit
together better. Furthermore, since proteins are folded from
chains of amino acids, when those chains have CONSISTENT
chemical properties (including charge distribution) along the
length of the chain it becomes possible to RELIABLY fold the
protein into the same shape most of the time.
If a protein is not folded properly, it is useless, or as in
cases like Mad Cow Decease, dangerous. Note also that chirality
is a problem in the pharmaceutical industry, where because they
cannot easily control chirality, a lot of reactions don't work
as well as they should.
So in summary, the answer to the question; what "function does
it [chirality] serve in *evolution*" is: It's part of what
makes it possible to reliably put together an organism with the
least amount of effort.
OK, now I want to make a general point about this question:
As far as I can tell chirality in no way helps the argument for
evolution or for ID/Creation, because it is something that works
well and pretty much has to be the way it is. If we assume that
evolution is true then this "problem" had to be solved for us to
get here. If we assume ID is true, then obviously the designer
would have made things that work. If you disagree I would like
to hear your reasoning.
In my opinion, one way to distinguish between evolution and ID
is by considering things that work, but could obviously be done
much better. I contend that a designer would not have made
obviously bad decisions. On the other hand, evolution should do
a lot of dumb things because it can only use what its got, and
cannot purposefully invent things for an intended purpose the
way a designer could. This is why evolutionists are always
talking about vestigial organs. I will give another example of
stupid design at the end of the discussion on sex.
Note also, that you suspected that I didn't know the answer to
this question. If I had not known, your argument still would
not have been an argument for ID. Things that we don't know are
not evidence for anything at all. Arguments are only valid when
they begin from facts we do know. Again, if you disagree, I
would like to see your reasoning.
[...]
>> ... I am not aware of any particular problem with bisexual
>> reproduction. What part of it do you believe is not
>> understood?
> Why did *nature* select for sexual reproduction vs asexual.
OK, the short answer to this question is: bisexual reproduction
allows species to adapt more quickly (in the fewest number of
generations). Species that adapt faster do better in the
evolutionary race. That of course tells you exactly nothing, so
I will now try to explain how it works.
Since you, unlike me, have taken highschool biology, you know
that bacteria reproduce asexually by simply dividing (fission).
This creates a clear problem for evolution. Consider a
hypothetical E-Coli bacteria (named Margaret) that divides in
such a way that she produces two daughter cells (Marg and Barb),
each of which has a new beneficial mutation. Lets say Barb has
an improved cell wall protein that helps protect her from phages
(bacterial viruses) while Marg has an improved ability to
neutralise some environmental toxin (say mercury).
Obviously, it would now be nice if we could eventually have a
single E-Coli bacteria that has both of these beneficial
characteristics. However, asexual reproduction provides no easy
way for this to occur. Since Marg and Barb will each continue
to produce daughters we have two populations of E-Coli, one with
mercury resistance, and the other with phage resistance, but not
both.
In fact, when under stress, bacteria will incorporate DNA that
is floating about in the environment, so with a lot of good
luck, these two beneficial characteristics may eventually wind
up in a single individual, but it is an inefficient hit and miss
affair.
By contrast, in sexually reproducing species this is hardly a
problem at all. If your son has improved resistance to mercury
and my daughter better resistance to viruses they can have
children, some of whom will have both characteristics. If these
characters improve the chances of their offspring surviving and
reproducing then eventually these characteristics will spread
through the entire population. At the same time other
beneficial characteristics from other individuals (like improved
brain cells and stronger achilles tendons) will also be
spreading through the entire population.
So, in short, sexual reproduction allows groups of breeding
individuals to rapidly spread beneficial characteristics
throughout the population. Thus all the individuals in the
population adapt faster and more efficiently.
Note that the same type of reasoning can be used to explain why
male/female sexual reproduction is marginally preferable to
hermaphrodite sexual reproduction. However, this point is not
central, so I will tell you how that works only if it happens to
be of interest to you.
Now, to conclude, I want to present you with an example of
stupid design as promised at the end of the first answer:
People (and other animals) do NOT reproduce entirely sexually!
(No, I am not talking about the virgin birth). Every cell in
your body includes a subcell called the mitochondria.
Mitochondria are passed exclusively down the female line. So
your mitochondria come from your mom, and your children will
inherit their mitochondria from their mother, and not from you.
NOTE:
There is currently a discussion about mitochondria going on
now in talk.origins (Subject: Why don't mitochondria have
junk DNA?). Here is a link to a post by John Harshman
answering one of my many questions:
http://groups.google.com/group/talk.origins/msg/b4eb4f3e6b48a718
If you read the first 25 or so posts in that thread, you will
learn a lot about mitochondria.
Among other things the DNA replication in the mitochondria is a
lot less efficient than in the rest of the cell. The problem is
so bad that a lot of the proteins used by the mitochondria are
now made in the main cell nucleus, not by the mitochondria
itself.
I believe this is clear evidence in support of evolution,
because it is a completely idiotic arrangement that appears to
have come about by chance, when two symbiotic cells united into
one more than a billion years ago. Can you think why a designer
would have done something so idiotic?
Sorry about being so long winded.
I really really tried to make it short and simple,
but failed miserably.
Hope to hear from you again;
loua...@yahoo.com
Nicholas wrote:
> Chris H. Fleming wrote:
> > NashtOn wrote:
>
> >>>problem with bisexual reproduction. What part of it do you
> >>>believe is not understood?
> >>
> >>Why did *nature* select for sexual reproduction vs asexual.
> >
> > My guess is genetic diversity.
>
> This is one of the interesting questions. We know that sexual
> reproduction helps diveristy and adaptation, but that is in hindsight.
> We know that sexual reproduction has a much higher cost than asexual
> reproduction. So given that evolution has no goals, what was it that
> drove the move to sexual reproduction in the first place?
There is an entire book which answers this question in clear, layman's
language; it's called "The Red Queen" by Matt Ridgely.
Nicholas
Cheers.
Nicholas
NashtOn
Thanks for the cordial reply. Time is running short on this Sunday
night, with kids to tuck in and preparing lunches.
Robert, I have heard about cytoplasmic inheritance since undergraduate
school, it's nothing new to me as I've heard it countless times. The
emerging field of epigenetics relies heavily on cytoplasmic inheritance.
If the symbiotic theory of cell organelles, mitochondia, ribo and
lysosomes and the list goes on and their alleged incorporation into the
cell decries this particular arrangement as being inefficient, I can
counter that it works and has worked for countless years. Who are we,
with science barely 100 years old to judge this characteristic of cell
biology. This does not support the ToE, rather it amplifies my belief
that the people that study biology and believe that the cell is
inefficiently designed, are arrogant.
As for sexual reproduction, how it appeared and how it is maintained, is
a plus towards the creationist's view of nature and a slap in the face
of evolutionary theory.
Questions that come to mind: How does recombining of genes support
generational transmission of mutations, especially the beneficial type
on which so much of the ToE has its foundation. Beneficial mutations are
diluted from one generation to the next and the expression of genes is
buffered, as it where.
Recombination has the potential to destroy beneficial arrangements of genes.
And your explanation about sexual reproduction spreading beneficial
genes more rapidly in a gene pool lacks experimental proof and is purely
conjecture.
As for chirality, it works both ways and in no way proves that
macroevolution is fact.
wf...@comcast.net
>As for sexual reproduction, how it appeared and how it is maintained, is
>a plus towards the creationist's view of nature and a slap in the face
>of evolutionary theory.
really? how do creationists say it arose?
oh. 'god did it'.
yeah that seems to answer any question including 'why did i get a flat
tire'
on this creationists build their 'science'
NashtOn
Yawn
--
Chris H. Fleming
> Chris H. Fleming wrote:
> > NashtOn wrote:
>
> >>>problem with bisexual reproduction. What part of it do you
> >>>believe is not understood?
> >>
> >>Why did *nature* select for sexual reproduction vs asexual.
> >
> > My guess is genetic diversity.
>
> This is one of the interesting questions. We know that sexual
> reproduction helps diveristy and adaptation, but that is in hindsight.
> We know that sexual reproduction has a much higher cost than asexual
> reproduction.
It would imagine that it would be extremely beneficial from an
evolutionary standpoint to make it somewhat difficult to reproduce.
This would act as a filter that keeps the weaker members from
reproducing.
Also, limits on reproduction can be good as well.
NashtOn
So what? If I want to read fiction, I wouldn't ask in an ng packed with
scientists.
Is there *any* experimental proof that sexual reproduction is more
beneficial, in an evolutionary sense, than asexual and is there any
experimental proof that it's even a random event, adopted by a great
number of species?
For that matter, except for the circumstantial evidence for the ToE, is
there any experimental evidence that it occurs on a macro level?
NashtOn
> Nicholas wrote:
>
>>Chris H. Fleming wrote:
>>
>>>NashtOn wrote:
>>
>>>>>problem with bisexual reproduction. What part of it do you
>>>>>believe is not understood?
>>>>
>>>>Why did *nature* select for sexual reproduction vs asexual.
>>>
>>>My guess is genetic diversity.
>>
>>This is one of the interesting questions. We know that sexual
>>reproduction helps diveristy and adaptation, but that is in hindsight.
>>We know that sexual reproduction has a much higher cost than asexual
>>reproduction.
>
>
>
> It would imagine
You would imagine? Why am I not surprised that another one of nature's
great mysteries is passed through the filter of the imagination of
evolutionists, who have no evidence?
that it would be extremely beneficial from an
> evolutionary standpoint to make it somewhat difficult to reproduce.
Right
Why?
> This would act as a filter that keeps the weaker members from
> reproducing.
>
> Also, limits on reproduction can be good as well.
Translation: Shooting in the dark, taking wild guesses and engaging in
speculation when, in fact,there is no proof, experimental or otherwise,
that sexual reproduction occurred according to any "known" mechanism of
macroevolution.
And since when is the dogma of evolution deterministic and why has this
method of reproduction been the norm through eons, with changing
environmental conditions and habitat at the same time that an enormous
degree of variation occurred since the Cambrian, according to the
believers in macroevolution? Let's face it, why, when so many other
characteristics changed dramatically, why didn't nature didn't "take a
chance" at asexual reproduction in mammals, for example?
And when will you evolutionists actually admit that you haven't an
inkling as to why many species reproduce in a way that is clearly at
great cost to them, with little or no demonstrable benefit?
And when will we ever see any experimental proof to any of the wild
guesses and unfounded speculation in biology, as it pertains to
macroevolution?
>
>
>
>>So given that evolution has no goals, what was it that
>>drove the move to sexual reproduction in the first place? To me genetic
>>diversity isn't a good answer as the orginal population would have been
>>asexual and hence wouldn't have derived much benefit from sex on that basis.
>>
>>Obviously gene swapping is useful (bacteria do it despite being asexual)
>>but why do it via sex? And why have male and female? Hermaphrodite
>>reproduction ensures sexual reproduction and that each individual
>>produces children, not just half.
>>
>>I can see why sex became so popular once it arrived, I just don't find
>>any of the existing explanations (or at least the ones I'm aware of) as
>>to how it came to be in the first place that convincing.
>>
>>Nicholas
>
>
Windy
NashtOn kirjoitti:
> > There is an entire book which answers this question in clear, layman's
> > language; it's called "The Red Queen" by Matt Ridgely.
> >
> So what? If I want to read fiction, I wouldn't ask in an ng packed with
> scientists.
Matt _Ridley_ is a scientist.
> Is there *any* experimental proof that sexual reproduction is more
> beneficial, in an evolutionary sense, than asexual
Yes, water fleas (Daphnia) and rotifers switch between sexual and
asexual reproduction all the time depending on what benefits them. If
you think the results have been misinterpreted, and sexual reproduction
is actually HARMFUL to these animals, you can do your own experiments
on them and prove it. Look for them in your nearest pond.
-- w
Ferrous Patella
> Friar Broccoli wrote:
>> NashtOn wrote:
>>
>>
>>>Did you miss the part where he asked about fur? Are you going
>>>to brush off the question and ridicule the OP even further?
>>
>>
>>>I don't think evolutionary "science" has any answers to these
>>>questions, just as they have no answers for sex, chirality and
>>>abiogenesis vs divine creation.
>>
>>
>> I agree that chirality is not understood nor abiogenesis
>> (assuming it occurred).
>
> Okay, so far.
>
> However, I am not aware of any particular
>> problem with bisexual reproduction. What part of it do you
>> believe is not understood?
>
> Why did *nature* select for sexual reproduction vs asexual.
AFAICT, there is a lot more asexual reprodection going on in nature.
--
Ferrous Patella (Homo gerardii)
T.A., Philosophy Lab
University of Ediacara
Å vite hva man ikke vet,
er også en slags allvitenhet.
loua...@yahoo.com
NashtOn wrote:
> loua...@yahoo.com wrote:
> > There is an entire book which answers this question in clear, layman's
> > language; it's called "The Red Queen" by Matt Ridgely.
> >
>
> So what? If I want to read fiction, I wouldn't ask in an ng packed with
> scientists.
The book is, of course, nonfiction.
No disappointment here. You've never had the stones to look at
contradictory evidence that might upset you before, I didn't really
expect it this time. But since you framed your remarks as a straight
question and a straight answer was available, I thought some lurker
might be interested in the information.
Cyde Weys
NashtOn wrote:
> Friar Broccoli wrote:
> > Also I am curious about why you think chirality might support ID
> > or creation. To me it just looks like another one of those dumb
> > "choices" made by evolution. Why would a designer have cared
> > about molecular handedness?
>
> The question one must ask oneself is not why a designer would have
> cared, but what purpose and function does it serve in *evolution*.
And that, folks, is an apt demonstration of everything that is wrong
with Intelligent Design. It doesn't matter one whit about what any
particular thing might say about the designer; all that matters is that
maybe it shows something wrong with evolution!
(I was split between nominating this for Chez Watt and answering it in
a serious fashion.)
Nicholas
Actually he didn't ask the questions with regard to sexual evolution, I
did and I do appreciate the reference.
Nicholas
Josh M.
"NashtOn" <na...@na.ca> wrote in message
news:MGmDf.3679$VV4.1...@ursa-nb00s0.nbnet.nb.ca...
You really are uncomfortable with anything that makes any intellectual
demands on you, aren't you? If things aren't in black and white, you get
frustrated and give up. That's not how science works; nothing is in black
and white. Rest assured you're not alone. This is demonstrative of
fundamentalist thinking.
loua...@yahoo.com
> Actually he didn't ask the questions with regard to sexual evolution, I
> did and I do appreciate the reference.
>
> Nicholas
Sorry for the confusion; I can only get here these days via Google. It
does, though, validate my theory that all creationist-sounding
questions should get straight answers even if they might be trolls,
because somebody somewhere really does want to know the answer.
(I also theorize that the best way to handle trolls is with politeness
and good cheer. Sometimes I slip, though.)
wf...@comcast.net
>Chris H. Fleming wrote:
>> Nicholas wrote:
>>
>>
>> It would imagine
>
>You would imagine? Why am I not surprised that another one of nature's
>great mysteries is passed through the filter of the imagination of
>evolutionists, who have no evidence?
wow. a man who believes in fairies and demons telling us how
irrational scientists are.
>
>And since when is the dogma of evolution deterministic and why has this
>method of reproduction been the norm through eons, with changing
>environmental conditions and habitat at the same time that an enormous
>degree of variation occurred since the Cambrian, according to the
>believers in macroevolution? Let's face it, why, when so many other
>characteristics changed dramatically, why didn't nature didn't "take a
>chance" at asexual reproduction in mammals, for example?
hmmm...seems evolution doesn't 'take a chance' on anything. it works
with what it's got. and if mammals didnt have the capability for
asexual reproduction, evolution was in no position to invent it
BUT..OTOH...if you're a creationist, this is no problem. god did it
can explain anything
>And when will you evolutionists actually admit that you haven't an
>inkling as to why many species reproduce in a way that is clearly at
>great cost to them, with little or no demonstrable benefit?
irrelevant. we dont have a cure for the common cold, yet viruses
exist. you trying 'god of the gaps'??
>
Greg G.
Nicholas wrote:
> Chris H. Fleming wrote:
> > NashtOn wrote:
>
> >>>problem with bisexual reproduction. What part of it do you
> >>>believe is not understood?
> >>
> >>Why did *nature* select for sexual reproduction vs asexual.
> >
> > My guess is genetic diversity.
>
> This is one of the interesting questions. We know that sexual
> reproduction helps diveristy and adaptation, but that is in hindsight.
> We know that sexual reproduction has a much higher cost than asexual
> reproduction. So given that evolution has no goals, what was it that
> drove the move to sexual reproduction in the first place?
Genetic recombination. Say there are beneficial mutations A and B that
enhance one another and are one in a million occurances. If the
population is a million or two, there's a good chance that both
mutations are present in the population. In asexual reproduction, it
will be about a million generations until both mutations occur in a
single line. With sexual reproduction, the mutations will be combined
in a couple of dozen generations. So, what sexual reproduction loses in
rapid reproduction is countered by rapid evolution.
> To me genetic
> diversity isn't a good answer as the orginal population would have been
> asexual and hence wouldn't have derived much benefit from sex on that basis.
It's about being able to take advantage of genetic diversity.
>
> Obviously gene swapping is useful (bacteria do it despite being asexual)
> but why do it via sex? And why have male and female? Hermaphrodite
> reproduction ensures sexual reproduction and that each individual
> produces children, not just half.
Evolution can be selfish. In hermaphroditic worms, a specimin has male
and female parts. The male parts have less cost to use than the female
parts as sperm requires less material than eggs. If a worm specializes
in being a sperm chucker it can produce more offspring by not wasting
resources producing eggs as most members of the species are potential
mates. Once the population has too many males, there is no advantage to
having only male parts or even any male parts as only a few will find a
mate, so then it would be advantageous to have exclusively female
offspring until there is a balance of advantages in the population.
>
> I can see why sex became so popular once it arrived, I just don't find
> any of the existing explanations (or at least the ones I'm aware of) as
> to how it came to be in the first place that convincing.
Above is the reasoning I used when I had nagging doubts similar to
yours.
>
> Nicholas
HTH
--
Greg G.
Crime does not pay ... as well as politics. --Alfred E. Newman
John Wilkins
> NashtOn kirjoitti:
>
>>> There is an entire book which answers this question in clear, layman's
>>> language; it's called "The Red Queen" by Matt Ridgely.
>>>
>> So what? If I want to read fiction, I wouldn't ask in an ng packed with
>> scientists.
>
> Matt _Ridley_ is a scientist.
I thought _Mark_ Ridley was a scientist and Matt was a popular science writer...
>
>> Is there *any* experimental proof that sexual reproduction is more
>> beneficial, in an evolutionary sense, than asexual
>
> Yes, water fleas (Daphnia) and rotifers switch between sexual and
> asexual reproduction all the time depending on what benefits them. If
> you think the results have been misinterpreted, and sexual reproduction
> is actually HARMFUL to these animals, you can do your own experiments
> on them and prove it. Look for them in your nearest pond.
>
> -- w
>
Windy
> >>> There is an entire book which answers this question in clear, layman's
> >>> language; it's called "The Red Queen" by Matt Ridgely.
> >>>
>
> > Matt _Ridley_ is a scientist.
>
> I thought _Mark_ Ridley was a scientist and Matt was a popular science writer...
Whoops :-) But isn't the writer Matt a kind of scientist too? And are
all these Matts part of the evo-conspiracy? ;-)
-- w
Nicholas
> Nicholas wrote:
>
>
>>Actually he didn't ask the questions with regard to sexual evolution, I
>>did and I do appreciate the reference.
>>
>>Nicholas
>
>
> Sorry for the confusion; I can only get here these days via Google. It
> does, though, validate my theory that all creationist-sounding
> questions should get straight answers even if they might be trolls,
> because somebody somewhere really does want to know the answer.
It wasn't actually intended to be a creationist type question: I'm an
evolution supporter. But I've not yet been fully satisfied with any of
the theories about the actual origin of sexual reproduction. Once it has
appeared the reason for continued existence seems clear: it's just
getting past that initial hurdle. I'll give your recommendation a try.
For the creationsists out there, not being satisfied with the theories
in existence does not disprove an entire concept: it just means a bit
more work to be done, or in my case a bit more reading perhaps. If you
wish to disprove evolution, you'll need some actual evidence that
contradicts it.
Nicholas
Nicholas
> Nicholas wrote:
>
>>Chris H. Fleming wrote:
>>
>>>NashtOn wrote:
>>
>>>>>problem with bisexual reproduction. What part of it do you
>>>>>believe is not understood?
>>>>
>>>>Why did *nature* select for sexual reproduction vs asexual.
>>>
>>>My guess is genetic diversity.
>>
>>This is one of the interesting questions. We know that sexual
>>reproduction helps diveristy and adaptation, but that is in hindsight.
>>We know that sexual reproduction has a much higher cost than asexual
>>reproduction. So given that evolution has no goals, what was it that
>>drove the move to sexual reproduction in the first place?
>
> Genetic recombination. Say there are beneficial mutations A and B that
> enhance one another and are one in a million occurances. If the
> population is a million or two, there's a good chance that both
> mutations are present in the population. In asexual reproduction, it
> will be about a million generations until both mutations occur in a
> single line. With sexual reproduction, the mutations will be combined
> in a couple of dozen generations. So, what sexual reproduction loses in
> rapid reproduction is countered by rapid evolution.
That makes a lot of sense once sexual reproduction occurs, but my
dissatisfaction is about the transition from asexual to sexual reproduction.
Having thought about it a bit since I wrote the original mail my comment
about bacteria sharing DNA stuck with me. It seems to me that some
adaptation of this mechanism could well provide a starting point for
sexual reproduction, but it's difficult to see why this should develop
from being of benefit to parent plus asexual children to only being used
for producing children. It seems likely, that like certain species
today, sexual reproduction only occurred initially when resources were
plentiful, but this also has the converse effect of it only coming into
effect when selection pressures are weakest. My old university textbooks
cop out on the issue altogether saying there must have been selection
pressures but making no attempts to speculate (admittedly they are cell
biology rather than ecology).
>> To me genetic
>>diversity isn't a good answer as the orginal population would have been
>>asexual and hence wouldn't have derived much benefit from sex on that basis.
>
>
> It's about being able to take advantage of genetic diversity.
>
>>Obviously gene swapping is useful (bacteria do it despite being asexual)
>>but why do it via sex? And why have male and female? Hermaphrodite
>>reproduction ensures sexual reproduction and that each individual
>>produces children, not just half.
>
>
> Evolution can be selfish. In hermaphroditic worms, a specimin has male
> and female parts. The male parts have less cost to use than the female
> parts as sperm requires less material than eggs. If a worm specializes
> in being a sperm chucker it can produce more offspring by not wasting
> resources producing eggs as most members of the species are potential
> mates. Once the population has too many males, there is no advantage to
> having only male parts or even any male parts as only a few will find a
> mate, so then it would be advantageous to have exclusively female
> offspring until there is a balance of advantages in the population.
I see your point, although acting as the female guarantees that the
offspring will be yours, and certainly at the level of worms (to my
knowledge) there is no burden of parental care.
It seems to me likely that sexual reproduction was hermaphroditic
initially (or do others disagree here?) and the advantages of being
being able to undertake both roles are clear, so why did sexual
differentiation occur? What would drive it so that half the population
can potentially mate only with the other half instead of everyone else?
And a siimilar question for the creationists no doubt salivating over a
'fatal flaw in evolution': why bother to design to sexes? What's the
point if the design is perfect in the first place? You don't need to be
able to adapt. Surely it would have been easier just to create Eve
initially and allow her to reproduce asexually. And it would certainly
have eliminated all the potential sexual sins from the get go.
Nicholas
Friar Broccoli
> Thanks for the cordial reply.
Thanks, being civil is easier all round.
This is just to let you know that I won't be replying until next
weekend.
Since I know, more or less, what I am going to say, and since it is low
stress and uncomplicated, I had intended to write you now,
but already on Monday evening I just don't have the energy.
My displayed Email address is good. Yours is a fake I presume.
So if you drop me a private "hello world", I will send you a
note shortly after I post a reply so that you know when and where
to look for it. (There is a slight chance that I will have an energy
spike
mid-week sometime.)
I look forward to continuing our conversation.
CMSchaum
> why has this method of reproduction [sexual] been the norm through eons, >
> with changing environmental conditions and habitat at the same time that
> an enormous
> degree of variation occurred since the Cambrian, according to the
> believers in macroevolution? Let's face it, why, when so many other
> characteristics changed dramatically, why didn't nature didn't "take a
> chance" at asexual reproduction in mammals, for example?
Actually asexual reproduction is the norm, sexual reproduction is the least
used by species.
> And when will you evolutionists actually admit that you haven't an
> inkling as to why many species reproduce in a way that is clearly at
> great cost to them, with little or no demonstrable benefit?
>
When will you creationists actually admit that you haven't an inkling as to
what Evolution actually does say and stop lying through your teeth about it?
rev.goetz
r norman wrote:
> On 28 Jan 2006 15:26:50 -0800, "rev.goetz" <jimgo...@yahoo.com>
> wrote:
>
> >
> >r norman wrote:
> >> On 28 Jan 2006 14:28:41 -0800, "rev.goetz" <jimgo...@yahoo.com>
> >> wrote:
> >>
> >> >
> >> >kyr...@gmail.com wrote:
> >> >> Why did humans out-evolve fur and hair? Almost no other mammal or
> >> >> marsupial has lost their hair.
> >> >
> >> >Charles Darwin wrote _The_ _Descent_ _of_ _Man,_ _and_ _Selection_ _in_
> >> >_Relation_ _to_ _Sex._ Perhaps there are ideas from this book that
> >> >could possibly explain how selection favored the loss of fur during
> >> >human evolution.
> >>
> >> There have been one or two papers written in biology since that time.
> >> A currently fashionable hypothesis for the present relates to
> >> parasitism.
> >> M. Pagel and W. Bodmer
> >> A naked ape would have fewer parasites
> >> Proc Biol Sci. 2003 Aug 7;270 Suppl 1:S117-9.
> >>
> >> http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12952654&dopt=Abstract
> >
> >How come this did not converge on all populations of apes?
>
> It isn't my hypothesis, but that abstract I cited says: "Hairlessness
> is made possible in humans owing to their unique abilities to regulate
> their environment via fire, shelter and clothing. Clothes and shelters
> allow a more flexible response to the external environment than a
> permanent layer of fur and can be changed or cleaned if infested with
> parasites. "
So this hypothesis predicts that the use of clothes preceded the loss
of fur in homines. Is that correct?
CMSchaum
"Nicholas" <nm...@netcomuk.co.uk> wrote in message
news:qFyDf.66193$zt1....@newsfe5-gui.ntli.net...
>
> That makes a lot of sense once sexual reproduction occurs, but my
> dissatisfaction is about the transition from asexual to sexual
> reproduction.
>
I'm not an expert by any means and someone will correct me if I'm wrong, but
aren't the three major reproductive methods pretty consistent with the
structure of the organism? I mean, single celled organisms are more likely
to be asexual vs multi-celled organisms which are variously sexual,
including hermaphroditic (like most plants and some worms), heterogonic
(many eusocial insects like bees), and asexual.
For species that are capable of both asexual and sexual reproduction they
can take advantage of a situation where their numbers are low, food is
plentify and there are few predatory influences at a particular time, such
as in the spring a species can use asexual reproduction to quickly increase
their numbers and later in the year, when their numbers are high, and the
environment harsher (less food, more predators) they can use sexual
reproduction to take advantage of gene mixing.
Greg G.
Nicholas wrote:
> Greg G. wrote:
> > Nicholas wrote:
> >
> >>Chris H. Fleming wrote:
> >>
> >>>NashtOn wrote:
> >>
> >>>>>problem with bisexual reproduction. What part of it do you
> >>>>>believe is not understood?
> >>>>
> >>>>Why did *nature* select for sexual reproduction vs asexual.
> >>>
> >>>My guess is genetic diversity.
> >>
> >>This is one of the interesting questions. We know that sexual
> >>reproduction helps diveristy and adaptation, but that is in hindsight.
> >>We know that sexual reproduction has a much higher cost than asexual
> >>reproduction. So given that evolution has no goals, what was it that
> >>drove the move to sexual reproduction in the first place?
> >
> > Genetic recombination. Say there are beneficial mutations A and B that
> > enhance one another and are one in a million occurances. If the
> > population is a million or two, there's a good chance that both
> > mutations are present in the population. In asexual reproduction, it
> > will be about a million generations until both mutations occur in a
> > single line. With sexual reproduction, the mutations will be combined
> > in a couple of dozen generations. So, what sexual reproduction loses in
> > rapid reproduction is countered by rapid evolution.
>
> That makes a lot of sense once sexual reproduction occurs, but my
> dissatisfaction is about the transition from asexual to sexual reproduction.
I would expect that any rudimentary form of sexual recombination would
approach optimization quite rapidly compared to the evolutionary pace
of asexual reproduction. Are there any primitive types of sexual
reproduction in the world today? I expect that the development of
sexual reproduction occured before the split between animals and
plants, however I wouldn't be surprized to learn that it developed more
than once.
Just a birth defect with inactive female parts that turned out to have
the advantage of not expending resources producing eggs.
>
> And a siimilar question for the creationists no doubt salivating over a
> 'fatal flaw in evolution': why bother to design to sexes? What's the
> point if the design is perfect in the first place? You don't need to be
> able to adapt. Surely it would have been easier just to create Eve
> initially and allow her to reproduce asexually. And it would certainly
> have eliminated all the potential sexual sins from the get go.
Right! Identical twins are separate people so why have genetic
differences at all?
>
> Nicholas
--
Greg G.
Good fences make good neighbors and electric fences keep their kids out
of the yard.
z
wrote:
>
>"Nicholas" <nm...@netcomuk.co.uk> wrote in message
>news:qFyDf.66193$zt1....@newsfe5-gui.ntli.net...
>
>>
>> That makes a lot of sense once sexual reproduction occurs, but my
>> dissatisfaction is about the transition from asexual to sexual
>> reproduction.
>>
>I'm not an expert by any means and someone will correct me if I'm wrong, but
>aren't the three major reproductive methods pretty consistent with the
>structure of the organism? I mean, single celled organisms are more likely
>to be asexual vs multi-celled organisms which are variously sexual,
>including hermaphroditic (like most plants and some worms), heterogonic
>(many eusocial insects like bees), and asexual.
The correlary between organismal complexity at a cellular leval and
sexuality works well for metazoans, but really breaks at the single
cell level. There are plenty of obligately sexual protists living
along side related species that have no apparent sexual phase. This
suggests that the ancestor to metazoans had seperate sexes.
>
>For species that are capable of both asexual and sexual reproduction they
>can take advantage of a situation where their numbers are low, food is
>plentify and there are few predatory influences at a particular time, such
>as in the spring a species can use asexual reproduction to quickly increase
>their numbers and later in the year, when their numbers are high, and the
>environment harsher (less food, more predators) they can use sexual
>reproduction to take advantage of gene mixing.
>
I keep meaning to take a more in depth look at the ecology of Bdelloid
rotifers, but they are an obligately asexual eukaryote. And they seem
to be fairly cosmopolitan in their distribution so they can't be
explained as an oddball. I have a feeling they are doing something
interesting when they do the micronucleus to macronucleus conversion,
but I vagully recall experiments that ruled that out.
>> Having thought about it a bit since I wrote the original mail my comment
>> about bacteria sharing DNA stuck with me. It seems to me that some
>> adaptation of this mechanism could well provide a starting point for
>> sexual reproduction, but it's difficult to see why this should develop
>> from being of benefit to parent plus asexual children to only being used
>> for producing children. It seems likely, that like certain species
>> today, sexual reproduction only occurred initially when resources were
>> plentiful, but this also has the converse effect of it only coming into
>> effect when selection pressures are weakest. My old university textbooks
>> cop out on the issue altogether saying there must have been selection
>> pressures but making no attempts to speculate (admittedly they are cell
>> biology rather than ecology).
>>
>
Sex is easier to explain if the enviroment changes rapidly.
B Miller
Friar Broccoli
[....]
> As for chirality, it works both ways and in no way proves that
> macroevolution is fact.
Hi again;
Each morning while coming to work, I think about my response,
and it occured to me that there is one very central aspect of
your position, that is a mistery to me, so I want to be sure it
is not overlooked while dealing with the minutia of more
detailed questions (like chirality etc). So could you tell me:
Why do you believe that God could not have used evolution as
His method for creating living things including human beings?
Is it because you believe the description in Genesis is
literally true, or is there some other reason or combination
of reasons?
Friar Broccoli
Again, I apologize for the length of this post. I hope the fact
that you are unlikely to see more than one of these windbag
efforts per week will mitigate in my favour, and you will thus
see fit to read and respond.
Before getting to the specific arguments you presented last
Sunday evening, I want to make some general comments about the
types of arguments you use against evolution, and how I hope to
counter them during our discussion.
Thus far all the arguments I have seen from you concern things
that we either do not know, or about which there is some doubt.
>From these uncertainties you conclude that the theory of
evolution must be wrong, and thus that creation must be true.
A clear example of this was your argument concerning chirality,
wherein you wanted to argue that somehow, because we didn't know
why it exists it must prove ID/creation, without any clear line
of connecting reasoning. It is clear to me that your arguments
concerning sexual reproduction have exactly the same form.
That is they say: -} We DON'T KNOW therefore ... {-
What I hope to do is point out four areas where we DO_KNOW
facts which point unequivocally toward evolution and away from
sudden creation. The 4 pillars on which I will build are:
1) The age of the universe as illustrated by the light from
distance galaxies.
2) The fossil and geological records including things like the
rock images we find of Trilobites, and the fossilized trunks
of extinct trees apparently rooted in coal seams.
3) Vestigial organs, a category into which I place mitochondria
along with the appendix, the wings on flightless birds etc.
4) The tree of life as supported by genetic data and the
fossil record.
In this discussion I hope you will seek out clear facts that
similarly support your creationist views, or consider why such
facts are unavailable.
I will return to this point (deriving conclusions from what we
KNOW) at the end of this post.
NashtOn wrote:
> If the symbiotic theory of cell organelles, mitochondia, ribo
> and lysosomes and the list goes on and their alleged
> incorporation into the cell decries this particular
> arrangement as being inefficient, I can counter that it works
> and has worked for countless years. Who are we, with science
> barely 100 years old to judge this characteristic of cell
> biology. This does not support the ToE, rather it amplifies my
> belief that the people that study biology and believe that the
> cell is inefficiently designed, are arrogant.
A proper discussion of the vestigial status of mitochondria will
require at least one long dedicated post, and if you consent to
continuing our conversation I am sure I will provide you with at
least one, so here I will make but one brief point:
Even if mitochondrial function was optimal, which seems
ridiculous on its face, it is still clearly vestigial because
it uses cell machinery that has a clear bacterial history.
One of the many clear piece of evidence for bacterial origins
of mitochondria is the fact that "antibiotics (anti*BACTERIAL*
drugs) such as chloramphenicol, erythromycin, and tetracycline
inhibit mitochondrial protein synthesis but have little effect
on cytosolic protein synthesis."
> As for sexual reproduction, how it appeared and how it is
> maintained, is a plus towards the creationist's view of nature
> and a slap in the face of evolutionary theory.
Your assertion above that sexual reproduction supports creation
is positive and thus (in my view) requires positive evidence.
But what you provide are questions and expressions of doubt
(things you DON'T KNOW):
> Questions that come to mind: How does recombining of genes
> support generational transmission of mutations, especially the
> beneficial type on which so much of the ToE has its
> foundation.
All versions of evolutionary theory agree that beneficial
mutations are extremely rare. Sexual reproduction is clearly
the most efficient way to move/combine these rare beneficial
mutations from separate individuals into a single individual
and thus into the population as a whole. See below for more
details.
> Beneficial mutations are diluted from one generation to the
> next and the expression of genes is buffered, as it where.
I puzzled over this odd comment for quite awhile. I suspect
the problem here is one of perspective. If, for example, you
pesonally have 2 children you have noted that one quarter of
your personal genetic information is going to be "lost". There
are at least two problems with this view:
1. the effects of selection are best viewed at a population
wide or species wide level.
2. replacement procreation (two parents averaging two children)
is highly unusual in evolutionary history.
Concerning the first point, to begin: nobody is claiming that
sexual reproduction produces perfect outcomes. It simply
produces different (and from my point of view "better") results
than asexual reproduction. As described in my previous post
asexual reproduction makes it very very difficult to get two
beneficial mutations from sister cells into a single
individual, who can then pass on both characteristics to
succeeding generations.
Sexual reproduction provides a natural and obvious way of
achieving such merging of characteristics, but that is not to
say that all (or even most) beneficial mutations make it into
the population. All that is claimed is that a lot MORE
beneficial mutations spread into a sexually reproducing
population. (This simple observation remains true despite many
other layers of complexity. Again, more specifics below.)
On the second point: until very recently four offspring per
human mother was low. Typically a female might have eight
children, only a few of whom would successfully reproduce. The
type of "buffering" you described would still occur, but there
would be a general tendency for beneficial characteristics
(including beneficial mutations) to be retained, while
detrimental characteristics, like a poor immune system or a
tendency to non-cooperative behaviour would be removed.
> Recombination has the potential to destroy beneficial
> arrangements of genes.
This is definitely true. As stated above sexual reproduction
is far from perfect, but like democracy, just "better" than all
the known alternatives.
> And your explanation about sexual reproduction spreading
> beneficial genes more rapidly in a gene pool lacks
> experimental proof and is purely conjecture.
This statement appears very strange to me. And I really wonder
what you could possibly be talking about. Your comment seems
to indicate that you agree that animal characteristics are
largely the result of and transmitted by genetic coding. So
what then do you doubt:
- that mothers and fathers provide the DNA found in their
offspring?
- that the contribution of genetic info from each parent is
a more or less random selection of half of their genome?
- that individuals who parent more offspring contribute more to
the populations' gene pool?
- that you become a parent by not dying before the age of
reproduction and then successfully finding a mate or mates to
reproduce with?
- that your genetic characteristics (like disease resistance)
have a lot to do with your chances of successfully mating and
reproducing?
As far as I can tell; for sexual reproduction to fail to spread
beneficial genes throughout the population, one of the above
statements must be false. Could you tell me which one is
false?
> As for chirality, it works both ways and in no way proves that
> macroevolution is fact.
I am glad we agree that what we DON'T KNOW about chirality
doesn't support either evolution or creation. I am sorry to
keep rubbing this "don't know therefore ..." stuff in, but I
believe a sustained attack against this type of erroneous
logic, is a first essential step in convincing you that
evolution must be true.
Concerning sexual selection, it is also not obvious to me that
it tells us anything that will allow us to distinguish between
creation and evolution. For one thing, it has so many complex
implications it is hard to know what we really_know about it
for sure. And again, what we don't know really can not tell us
anything at all.
So, if you are agreeable, I would like to move on to a
presentation of evidence concerning things we do know for sure.
Is that OK with you?
If you will accept this change of focus in this discussion, I
will work from my list of four pillars presented at the
beginning of this post.
Finally, as I mentioned in my Wednesday post, which you may
have missed, I would like to know:
What do you know about God that leads you to believe that He
William Morse
news:8a0ot1htmrl1vh1hm...@4ax.com:
I have seen another hypothesis that the loss of fur was to reduce the
risk of fur catching fire. As you noted earlier, there may have been more
than one reason, and in the case of fire the effects may have been
synergistic.
Yours,
Bill Morse
William Morse
news:qFyDf.66193$zt1....@newsfe5-gui.ntli.net:
> It seems to me likely that sexual reproduction was hermaphroditic
> initially (or do others disagree here?) and the advantages of being
> being able to undertake both roles are clear, so why did sexual
> differentiation occur? What would drive it so that half the population
> can potentially mate only with the other half instead of everyone
> else?
I asked a similar question on sci.bio.evolution a while back, and was given
a very good response by Wirt Atmar. I just tried to find the response on my
computer, but with no success. You can try googling groups, limiting the
group to sbe and the author to Wirt.
Yours,
Bill Morse
Nicholas
Thanks: think I found it if it it;s the thread about the aphids etc.
Didn;t quite follow all his logic so posted a follow up. However, it
didn't really seem to address the question of how sexual reproduction
arose in the first place, just the advantages of it once the ability
already existed and of switching in species that were capable of it.
Nicholas
William Morse
news:HedGf.15896$Fy4....@newsfe4-win.ntli.net:
Ok, sorry - I apparently misunderstood your question. I thought you were
asking why the two sexes should be different. Your question instead is (I
think) why a species would choose obligate sexual reproduction over
hermaphroditic reproduction, since the latter would appear to have the
best of both worlds. That is also a good question, but unfortunately I
don't have a good answer. I will note that there are fish which can
change their sex - when the male in the group dies, the dominant female
changes sex to become male. I will also note that sex in many reptiles is
determined by the temperature at which the eggs are incubated. So there
is perhaps more plasticity than one might think.
Yours,
Bill Morse
r norman
wrote:
There are also animals like the water flea, Daphnia, that reproduce
asexually with no production of males when times are good and switch
to sexual reproduction under times of stress. Many other animals,
like jellyfish and many parasites, have some life stages that
reproduce asexually and other stages that reproduce sexually.
To look for the origin of sexual reproduction, you have to look
beyond animals, though, since it is found in plants, fungi, and even
single-celled protists. The main aspect of sexual reproduction is
alternation of diploid and haploid involving alternation of meiosis
and fertilization. Only secondarily comes sexual dimorphism, first of
the gametes into small, motile sperm and large, nutritive ova, then of
the organisms that produce the gametes into male and female.