Re: Out of E.Asia II
David Marcus Woodcock (dmw@engin.umich.edu)
17 Nov 1995 05:10:55 GMT
Phil Nichols [PN] replied to my respons to James Shreeve:
DW> I know of no record of transition from erectus to modern found
DW> in Africa or the mideast. I do know of finds described as
DW> modern dated to about 100 kya in S.Africa,Eithiopia and the Mideast.
DW> And I know of much older erectus finds in E.Africa. I don't
DW> know of any finds that appear transitional between the 2 grades
DW> from that part of the world. To my knowledge all the finds
DW> dated between the erectus finds and the 100 kya moderns from Africa
DW> appear to be transitional between erectus and neandertal.
DW> But I'd welcome any references to any finds that do appear to
DW> fit in a series from erectus to moderns.
PN> Your account is somewhat ambiguous. If by "Modern" you mean
PN> "anatomically modern Homo sapiens" then you are mistaken.
How is that ambiguous ? I trust you are not one of those who
supposes that these folks had functionally different
brains [ in identical skulls within range of variation !]
merely because their technology was not where it would be
60 kya later.
PN> There are a number of fossils from Africa usually labeled
PH> "archaic Homo sapiens" that show some Homo erectus and some
PH> modern Homo sapien traits. Hear are two examples.
PN>Elandsfontein (S. Africa)
PN>skull cap and mandibular fragment dated (faunal dating)
PN>500,000-200,000 years ago. maximum breadth near the base, massive
PN>browridge and flat, receding frontal bones are characteristic of Homo
PN>erectus. Estimated cranial capacity (1,200 - 1,250), relatively broad
PN>frontal and rounded occipital areas are more like Homo sapiens.
PN> Broken Hill (Zimbabwe)
PN> Complete cranium plus cranial fragments from another individual
PN> Massive face, large brow ridges, flat, receding frontal, large basal
PN> breadth BUT cranial capacity of 1,280cc, more rounded occipital and
PN> broad frontal. Dated to late middle quaternary,no later than 130,000
PN> years ago.
PN> In fact, all of the fossil finds from Africa that fall within the
PN> 500,000 - 200,000 range appear to show a mosaic of Homo erectus and
PN> Homo sapiens traits. They are not transitional to neandertals as
PN> neardertal morphology is rather unique in many respects. None of
PN> these materials show the enlarged nose, mid-facial prognathism,
PN> occipital bun or suprainiac fossa.
Thank you for the references and the correction. In my
enthusiasm I oversimplified and used neandertal when I should
have used neandertal-like SW type. I think the African
population of from about 200 to 110 kya was more similar
to early neandertals than it was to E.Asian [H.s.s. trending]
groups of the same era, but certainly didn't exhibit H.s.n. boreal
adaptations such as the large nose. And judging by mideastern
neandertals it was probably more gracile. Occipital bun
appears to follow the posterior cranial expansion,
thus rounding, of the back cranium. Moreover it's not found in all
neandertals. I doubt it would occur in this SW group.
However, I don't expect to find the much reduced brow ridges,
smaller face, and higher forehead found in H.s.s. either.
Now consider whether the Broken Hill type ,assuming a date
of 300-200 kya is a better fit as an ancestor for this SW
type or for H.s.s. Note that several early neandertals also
have erectus like prognathism.
At this point a critic may object that I'm doing exactly
what the OOA folks are doing with regard to the E.Asian
fossils -- simply dismissing plausible transitional types
between erectus and modern as leading to a dead end. Well,
almost. The E.Asian series do get closer to the modern
condition -- reduction in face, more rounded frontal than
Broken Hills does. Thus in the East the trend seems more
cleatly toward H.s.s. than it does in the West. In the
West we know European archaics [Heidelberg,Swanscombe] led
to neandertal. It's not implausible to suppose something
similar happened across the Med.
James Shreeve has pointed out to me [in email]
that neither OOA's or multiregionalists think so.
Well,naturally. MRs used to think [and some still do] that
humans evolved from erectus grade to H.s.s. everywhere in
the old world including Europe. And a case can made for
a transition in Africa; Phil just made it. But it doesn't
seem so strong once you question whether Homo was
evolving into H.s.s. everywhere from 300 to 120 kya.
PN> In my opinion,the transition in Africa is as well documented as that
PN> in Asia and occurs earlier. However, I am not an advocate of the
PN> replacement hypothesis.
Given the example you've given and the dating limitations in both
Africa and E.Asia I'm puzzled by this assertion.
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