Re: Homo Erectus Finds!
David Marcus Woodcock (dmw@engin.umich.edu)
9 Feb 1995 03:13:25 GMT
In article <3h3ot0$vk@newsbf02.news.aol.com>,
Hideo Gump <hideogump@aol.com> wrote:
>
> Recent evidence from Java seems to indicate that homo erectus
>was
>still in Java/Indonesia about the same time as archaic homo sap was in
>Africa,
>the Middle East and Europe.I find it surprising that this ancesteral
>group would have coexisted with modern looking humans
Well, isolated populations have occurred from time to time.
But see below:
>This has happened throughout
>our history. Cro-magnon and Neandertal in Europe and the Middle East,
But neandertal was probably not ancestral to modern humans
[save for a few genes in modern populations mainly in the west]
Here is what I think was happening: Homo is a large, wideranging
genus that can and will exploit a wide variety of biomes. This is
obviously the case since the Neolithic, but was true to a lesser
extent since Homo evolved. At certain periods some populations
became somewhat genetically isolated and diverged to some extent.
Later more successful groups from one edge of the Homo range
traveled to the other edge in a few generations. Thus we find
rather different types as neighbors.
An example is the neandertal/cro-magnon split.
This may be linked to the bottleneck that seems to have existed
between E.Asia [Asia east of the Himalayan ice sheet,Siberian
ice sheet and Burmese jungle] and the West [rest of Old World]
The Acheulian tool type doesnt appear in E.Asia til about
100 000 BP; it appeared in the West more than 1 million years
earlier. Best evidence
is that H.s.sapiens evolved in E.Asia; Wolcott and collaborators
have two nice series of skulls from China and SE Asia grading
from H.erectus to H.s.sapiens. To my knowledge no neandertal
or neandertaloid skulls have been found in E. Asia. In the
West however we have neandertal and similar skulls from
Europe and Africa. We don't have a series as complete from
erectus to neandertal as is the E.Asian series. But what we
have, e.g. heidelberg man, would fit on such a series. Then
about 100 000 years ago H.s.sapiens appears in the levant about
the same time neandertals are found there.
>Homo Erectus, and 2 Australopithecine species in Africa.
>The same article in
>Discover magizine in which I read about the recent age of fossils
>found in Java says that
>the oldest erectus fossils found there are almost as old as erectus
>findings in
>Africa which would explain the abscence of stone tools with the bones.
>There
>were no stone tools associated with these sites because the migration
>to this
>part of Asia took place before they were invented. There I've said it!
>Any opinion or info on this subject will be greatly appreciated.
> Still Yours,
> Hideo Gump
To my knowledge the oldest erectus known in Africa dates back no
further than 1.6 Myr [Turkana]. Russell Showhan [sp?] has
erectus in China to 1.9 Myr. Erectus in Java dates at least to
1.7 Myr. The co-presence of erectus and 2 other hominid species
may be another example of divergence between E.Asian and
Western populations followed by migration of E.Asian groups
[erectus] west. Yes, I agree with Showhan[sp?] that erectus
evolved in Asia; it's an hyposesis I've entertained since 1981;
one I think I adopted from the man who discovered a Homo
fossil in Java dated [disputed then] to 1.8 Myr.
[This is from memory of a secondary source --the hominoid selection
from
V.J. Maglio and H.B.S. Cooke
(eds.). Evolution of African Mammals. Harvard University Press.
1978.
However, stone tools were developed in Africa by 2.5 Myr,probably
earlier. I doubt preHomo left Africa without them.
Java finds are probably not associated with tools because they
are as far as I know not dwelling sites but bodies found in
old riverbeds, i.e. since Oldowan tools were of limited use
[ie for butchering,cutting] most individuals probably didnt
carry them around with them most of the time; they have been
found at the old China site.
Philip "Chris" Nicholls answers Hideo:
>I think what the article was talking about was the
>absense of bifaces (so-called "hand-axes") and other tools associated
>with the African Acheulean tool industry in Asian Homo erectus sites.
Acheulian is found in Asia [ eg in Indian forest 500 000 BP] but
not in E. Asia. There was no significant barrier between Africa
and West Eurasia during the glacials. I realize this is probably
what you meant, just wished to clarify it.
>My personal opinion is that we have underestimate the number of
>species present between 500,000 and 100,000 years ago (well, not my
>own idea, but one I agree with). If you think about it, this would
>fit in nicely with a Punctuated-equalibrium type scenerio and might
>also account for the conflicting evidence that has produced the
>"Origins of Modern Homo sapiens" debate.
I think calling the co-existing populations of Homo that
existed 500-100k separate species just confuses matters.
Most folks think species difference means inability to interbreed
to produce fertile offspring. Of course with current taxonomy of
large mammals [eg red wolves and coyotes] this is often not the case.
However, subspecies seems a preferable term. Moreover I agree with
those who would conflate H.sapiens and H.erectus.
I think there has always been just one species of Homo; no
population diverged enough so it couldnt/wouldnt interbreed with
the rest. Homo habilis ? If Homo was an example of
punctuated equilibrium-- an opportunistic forager from the
tropics rapidly evolving to a temperate zone hunter -- then habilis
may be the far edge of a population rapidly changing elsewhere.
This would explain both why its examples don't fit as nice
intermediates between A.afarensis and Homo, and why it's found
co-existing with H.erectus at the same place.
BTW I think A.afarensis, A.robustus/boisei and the Black Skull
speciman could fit the divergence/migration pattern outlined above.
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David Woodcock
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