Now, habilis and erectus are now thought to be sister species that overlapped in time.
The new fossil evidence reveals an overlap of about 500,000 years during which Homo habilis and Homo erectus must have co-existed in the Turkana basin area, the region of East Africa where the fossils were unearthed.
"Their co-existence makes it unlikely that Homo erectus evolved from Homo habilis," said co-author Professor Meave Leakey, palaeontologist and co-director of the Koobi Fora Research Project. . . . . . "
This find is extremely puzzling to standard PA, leading to all manner of weird theories (see rest of article) such as that Habilis and Erectus were able to co-exist because they were not competitive and occupied quite distinct niches.
What a laugh!
It is, in fact, a beautiful confirmation of my proposal that inland sites (such as Lake Turkana) were those of hominid 'refugees' fleeing from their coastal habitats. None of them would ever have lived in that area for more than a short time, and it is most unlikely that any ever raised infants to maturity in that location.
These two individuals might have been members of small parties which occupied this site in succeeding years. They certainly did not occupy it together.
Although it is surprising that the hostility between separate groups of coastal hominids was so great, and so persistent over so many hundreds of thousands of years, that they were able to evolve into such different species or (IMHO more accurately) sub-species.
> Now, habilis and erectus are now thought to be sister species > that overlapped in time.
> The new fossil evidence reveals an overlap of about 500,000 years > during which Homo habilis and Homo erectus must have co-existed > in the Turkana basin area, the region of East Africa where the fossils > were unearthed.
> "Their co-existence makes it unlikely that Homo erectus evolved > from Homo habilis," said co-author Professor Meave Leakey, > palaeontologist and co-director of the Koobi Fora Research Project. > . . . . . "
> This find is extremely puzzling to standard PA, > leading to all manner of weird theories (see > rest of article) such as that Habilis and Erectus > were able to co-exist because they were not > competitive and occupied quite distinct niches.
> What a laugh!
> It is, in fact, a beautiful confirmation of my > proposal that inland sites (such as Lake > Turkana) were those of hominid 'refugees' > fleeing from their coastal habitats. None > of them would ever have lived in that area > for more than a short time, and it is most > unlikely that any ever raised infants to > maturity in that location.
> These two individuals might have been > members of small parties which occupied > this site in succeeding years. They > certainly did not occupy it together.
> Although it is surprising that the hostility > between separate groups of coastal > hominids was so great, and so persistent > over so many hundreds of thousands of > years, that they were able to evolve into > such different species or (IMHO more > accurately) sub-species.
> Paul.
Why fleeing, and not simply expanding up the Rift during a long wet period or sea level rise or tectonic shift there?
>From 2004, another small H er skull from Kenya, said to be teen
>> It is, in fact, a beautiful confirmation of my >> proposal that inland sites (such as Lake >> Turkana) were those of hominid 'refugees' >> fleeing from their coastal habitats. None >> of them would ever have lived in that area >> for more than a short time, and it is most >> unlikely that any ever raised infants to >> maturity in that location.
>> These two individuals might have been >> members of small parties which occupied >> this site in succeeding years. They >> certainly did not occupy it together.
>> Although it is surprising that the hostility >> between separate groups of coastal >> hominids was so great, and so persistent >> over so many hundreds of thousands of >> years, that they were able to evolve into >> such different species or (IMHO more >> accurately) sub-species. > Why fleeing, and not simply expanding up the Rift during a long wet > period or sea level rise or tectonic shift there?
It is simply the case that hominids are a coastal taxon. Try sleeping outside without a tent or blankets, and you'll soon find out what I mean. The cold is bad enough, but you won't survive long (at any distance from the sea) when the ground is wet from rain or other sources. Even if well-fed adults can manage it for a while, infants have almost no chance of survival.
Question: Why didn't some populations re-acquire hair, make other adaptations, and move inland?
Answer: The problems were just too great. Diurnal primates have no adaptations for sleeping on cold wet ground at night. Hair is worse than useless in those conditions. Moving back into the trees (and growing hair) was the only feasible option, but chimps were already there, and the adaptations back to tree-living were just too huge. The coastal hominids were nearly always strong, and usually trying to export their genes inland -- which while never being successful, was enough to disrupt any population's attempt at an adaptation to a non-coastal life.
> Now, habilis and erectus are now thought to be sister species > that overlapped in time.
> The new fossil evidence reveals an overlap of about 500,000 years > during which Homo habilis and Homo erectus must have co-existed > in the Turkana basin area, the region of East Africa where the fossils > were unearthed.
> "Their co-existence makes it unlikely that Homo erectus evolved > from Homo habilis," said co-author Professor Meave Leakey, > palaeontologist and co-director of the Koobi Fora Research Project. > . . . . . "
> This find is extremely puzzling to standard PA, > leading to all manner of weird theories (see > rest of article) such as that Habilis and Erectus > were able to co-exist because they were not > competitive and occupied quite distinct niches.
> What a laugh!
> It is, in fact, a beautiful confirmation of my > proposal that inland sites (such as Lake > Turkana) were those of hominid 'refugees' > fleeing from their coastal habitats. None > of them would ever have lived in that area > for more than a short time, and it is most > unlikely that any ever raised infants to > maturity in that location.
> These two individuals might have been > members of small parties which occupied > this site in succeeding years. They > certainly did not occupy it together.
> Although it is surprising that the hostility > between separate groups of coastal > hominids was so great, and so persistent > over so many hundreds of thousands of > years, that they were able to evolve into > such different species or (IMHO more > accurately) sub-species.
> Paul.
why stack speculation on speculation? We can be sure, that in the absence of modern man that hominids speciated and adapted to multiple habitats everywhere they could get to. We will eventually perhaps find the evidence to show this, but in the meantime our evidence is geographically restricted.
>> http://news.bbc.co.uk/2/hi/science/nature/6937476.stm >> The new fossil evidence reveals an overlap of about 500,000 years >> during which Homo habilis and Homo erectus must have co-existed >> in the Turkana basin area, the region of East Africa where the fossils >> were unearthed. >> This find is extremely puzzling to standard PA, >> leading to all manner of weird theories (see >> rest of article) such as that Habilis and Erectus >> were able to co-exist because they were not >> competitive and occupied quite distinct niches. > why stack speculation on speculation?
You think that the 'conclusions' of Meave Leakey, Chris Stringer and Fred Spoor are solid fact?
When we are trying to work out what might have happened in hominid evolution, all we can do is theorise (or speculate) on the evidence found. As new evidence emerges, some theories will be seen to be weak and others will gain strength. This new evidence is excellent backing for mine, whereas it makes the standard theories appear more foolish than ever. Leakey, Stringer and Spoor don't sound too happy about their 'separate niches' theory -- but what else can they propose?
Is anyone here going to try to defend the idea that there were two wholly different species of hominid in the tropical African uplands, shared the same habitat -- but occupied different niches -- for half a million years, in climatic conditions that were generally much drier than today? The notion is beyond absurdity.
> We can be sure, that in the > absence of modern man that hominids speciated and adapted to multiple > habitats everywhere they could get to.
That is NOT the theory. These two species were supposedly occupying the same habitat. In any case, the distinctive feature of hominids has long supposed (IMO correctly) to have been their ability to modify their culture, rather than their anatomy. Ancestral hominids are certainly not thought to have been specialists, but generalists able to exploit a very wide range of resources. If this is true (which I am sure it is) then it is quite absurd to entertain the idea of two non-competing species of hominid living peaceably together around 1.5 mya.
> We will eventually perhaps > find the evidence to show this, but in the meantime our evidence is > geographically restricted.
I have no idea what you are talking about here, nor how it is supposed to be relevant to the topic.
> >> It is, in fact, a beautiful confirmation of my > >> proposal that inland sites (such as Lake > >> Turkana) were those of hominid 'refugees' > >> fleeing from their coastal habitats. None > >> of them would ever have lived in that area > >> for more than a short time, and it is most > >> unlikely that any ever raised infants to > >> maturity in that location.
> >> These two individuals might have been > >> members of small parties which occupied > >> this site in succeeding years. They > >> certainly did not occupy it together.
> >> Although it is surprising that the hostility > >> between separate groups of coastal > >> hominids was so great, and so persistent > >> over so many hundreds of thousands of > >> years, that they were able to evolve into > >> such different species or (IMHO more > >> accurately) sub-species. > > Why fleeing, and not simply expanding up the Rift during a long wet > > period or sea level rise or tectonic shift there?
> It is simply the case that hominids are > a coastal taxon. Try sleeping outside > without a tent or blankets, and you'll > soon find out what I mean. The cold > is bad enough, but you won't survive > long (at any distance from the sea) > when the ground is wet from rain or > other sources. Even if well-fed adults > can manage it for a while, infants have > almost no chance of survival.
> Question: Why didn't some populations > re-acquire hair, make other adaptations, > and move inland?
> Answer: The problems were just too > great. Diurnal primates have no > adaptations for sleeping on cold wet > ground at night. Hair is worse than > useless in those conditions. Moving > back into the trees (and growing hair) > was the only feasible option, but chimps > were already there, and the adaptations > back to tree-living were just too huge. > The coastal hominids were nearly always > strong, and usually trying to export their > genes inland -- which while never being > successful, was enough to disrupt any > population's attempt at an adaptation > to a non-coastal life.
> Paul.
I disagree with the word fleeing, preferring expanding due to population pressure. I think there were coastal hominids in the rift when it connected with the Indian Ocean and also north of the Red Sea in that rift, where we find neandertals and early Hs later on. But as you say, the inland groups had it worse and weren't able to adapt as well to the inland ecology without becoming more arboreal as chimps did. Only when boats were developed could Homo stay inland sustainably, with trade to the coasts in some form.
>> >> It is, in fact, a beautiful confirmation of my >> >> proposal that inland sites (such as Lake >> >> Turkana) were those of hominid 'refugees' >> >> fleeing from their coastal habitats. > I disagree with the word fleeing, preferring expanding due to > population pressure.
The difference is huge -- since ALL species seek to expand 'due to population pressure'; nearly all do it in most years.
Individuals (often juveniles) of those species will move out from their natural habitat, into foreign ones where they will die. IF their fossils survive in such circumstances, no competent scientist will suggest that they lived in that environment.
Unfortunately there is an almost complete absence of competence among those scientists who claim to study human evolution.
> I think there were coastal hominids in the rift
If there were hominids in the rift (and they were not transient refugees) then they were not coastal hominids.
> when it connected with the Indian Ocean and also north of the Red Sea > in that rift, where we find neandertals and early Hs later on. But as > you say, the inland groups had it worse and weren't able to adapt as > well to the inland ecology
Either they adapted, successfully reproduced, and had a viable population (and became another species), or they were transient 'refugee' individuals.
> Finds test human origins theory By James Urquhart
He's right about it being a test. But he does not see that standard theory fails -- and fails hopelessly.
This find is of great importance, with major implications for the science. This article (no doubt an accurate summary of the one in Nature) does not notice them and provides several classic instances of the near-total incompetence of modern PA.
> Previously, the hominid Homo habilis was thought to have > evolved into the more advanced Homo erectus, which evolved > into us. > Now, habilis and erectus are thought to be sister species that > overlapped in time. > The new fossil evidence reveals an overlap of about 500,000 > years during which Homo habilis and Homo erectus must > have co-existed in the Turkana basin area, the region of East > Africa where the fossils were unearthed. > "Their co-existence makes it unlikely that Homo erectus evolved > from Homo habilis," said co-author Professor Meave Leakey, > palaeontologist and co-director of the Koobi Fora Research > Project.
When you have a bad theory, you misread the data. That drives you into even worse theories, more misreading, and so on in a vicious circle. In a discipline like PA, with no tradition of hard debate nor internal criticism the speed of the circling becomes manic and soon everything is total nonsense.
One basic mistake is in the assumption that the hominids lived where they died. That would be reasonable for most fossils -- although far from all -- and here there are several factors that make it questionable, none of which have occurred to the authors of the paper.
Firstly, for nearly all this period (focussing on the half-million years when both species are thought to have been present) this area was barren desert. Africa generally was much drier than today. While, for brief and exceptional intervals, there might have been sufficient resources for one species of hominid, none could have survived there in for the bulk of the time, and there certainly was never enough for two species.
Secondly, no remotely plausible niche has ever been identified for a hominid in upland Africa. Most PA people 'think' that early hominids competed with lions, hyena and other pure carnivores, in both hunting and in scavenging.
Thirdly, there is the presence of two distinct hominid species, apparently co-resident for the whole period.
> The jaw bone was attributed to Homo habilis because of its > distinctive primitive dental characteristics, and was dated to > around 1.44 million years ago. > It is the youngest specimen of this species ever found.
> The skull was assigned to the species Homo erectus despite > being a similar size to that of a habilis skull. Most other erectus > skulls found have been considerably larger.
> The researchers dismiss the idea that the small size of the skull > could be a result of it belonging to a youngster. > "By studying how the skull bones are fused together we discovered > it belonged to a fully grown young adult rather than a developing > juvenile erectus," said Professor Spoor.
It now seems that Erectus females were much smaller than males. This will enable (simply on the basis of size) the sexing of many existing unsexed fossils. Yet there is no explanation (nor thought to be any need for one) as to why nearly all Erectus fossils are male.
> The new dates indicate that the two species must have lived > side by side.
The notion that two hominid species could have shared the same habitat is so absurd, that one has to wonder what these researchers were smoking. (But, unhappily, the answer is that nothing is too absurd for modern PA.)
> Sister species
> "The fact that they stayed separate as individual species for a > long time suggests that they had their own distinct ecological > niches, thus avoiding direct competition," Professor Leakey > explained.
> Professor Chris Stringer, head of human origins at London's > Natural History Museum, said: "Both were apparently stone tool- > makers, but one possibility is that the larger and perhaps more > mobile erectus species was an active hunter, while habilis > scavenged or caught small prey."
These idiots don't realise that 'tools' = 'weapons'. Assuming that both species were partly carnivorous (as is entirely reasonable, and as Stringer believes) then how could they NOT be competitors? Almost ALL carnivores compete -- that is a fact of natural history. Lions hate hyenas, but they also detest jackals and dislike foxes. They kill any other carnivore they can which crosses their path -- and likewise for hyenas. Jackals will kill foxes, and the smaller species will gang up on the larger ones whenever they can.
> It is most likely that both species evolved from a common ancestor.
> If Homo erectus had evolved from habilis and stayed within the > same location then both must have been in direct competition > for the same resources.
> Eventually, one would have out-competed the other.
The 'logic' here is desperate. It seems that if species A is the parent of species B, then both A and B will occupy much the same niche. BUT (according to the authors) if species A is the parent of species B and of species C, then B and C can occupy different niches.
Makes sense? Nah -- but, hey, this is PA and anything goes.
> Other possibilities
> But the linear, ancestor-descendent relationship between the two > species cannot be ruled out altogether. > Fred Spoor, professor of developmental biology at University > College London, and co-author of the paper, told the BBC News > website: "It's always possible that Homo habilis lived, let's say, > 2.5 million years ago and then in another part of Africa, away > from the Turkana basin, an isolated population evolved into > Homo erectus."
Spoor does not realise that hominid populations will readily impose isolation upon themselves (as the result of intense and violent competition with neighbouring populations), often with no, or minimal, assistance from geography.
> After a sufficient amount of time to allow both species to develop > different adaptations and lifestyles, Homo erectus could have > then found its way to the Turkana basin. > With separate "ecological niches", both species could co-exist > without direct competition for resources.
The problem with this 'solution' (not noticed by Spoor or any other PA) is that the isolation of a population will not result in the occupation of a different niche. Even if the two populations (now different species) have "different adaptations and lifestyles", they are still going to exploit the same resources.
> "But that is a much more complex proposition," Professor > Spoor explained, "the easiest way to interpret these fossils is > that there was an ancestral species that gave rise to both of > them somewhere between two and three million years ago."
Hopeless -- and beyond hopeless. Surely it is possible to work out -- from its anatomy-- the resources a fossil species was likely to exploit? Yet no PA involved in this matter makes such an attempt -- apart from Chris Stringer's ludicrous notion of 'big prey and small prey'.
> Not so similar > The fossil record indicates that modern humans (Homo sapiens) > evolved from Homo erectus. > However, to some researchers, the small size of the erectus > skull suggests that species may not have been as similar to > us as we once thought.
This last bit is an implicit recognition that "we haven't a clue what was going on" and a desperate grab for some "scientific respectability" -- by referring to some ancient and well-accepted doctrine. Inevitably the result is an embarrassing pratfall.
> On average, modern humans display a low level of "sexual > dimorphism", meaning that males and females do not differ > physically as much as they do in other animals. > The scientists compared the small skull to a much larger > erectus cranium found previously in Tanzania. If the size > difference between the two is indicative of the larger one being > from a male and the smaller being from a female, it suggests > that erectus displayed a high level of sexual dimorphism - > similar to that of modern gorillas. > Sexual dimorphism can relate to reproductive strategies and > sexual selection. > If erectus was very sexually dimorphic it may have had multiple > mates at a time. This differs from the more monogamous nature > of modern humans, indicating that Homo erectus was not as > human-like as once thought.
The rule of 'large dimorphism' = 'multiple mates' is no more than rough and ready. Large dimorphism can have many other origins. The standard rough 'rule' is not likely to apply in a highly unusual tool- and weapon-using taxon. The best guide to ancestral hominid social structure is that of the extant species -- humans. -----------------------
Here, folks, we see modern PA at the very cutting edge of the 'science'.
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