212 CHAPTER 9 | The Global Expansion of Homo sapiens and Their Technology
North Africa exhibit the kind of midfacial flatness pre-
viously seen only in East Asian fossils; similarly, various
Cro-Magnon fossils from Europe show the short upper
jaws, horizontally oriented cheek bones, and rectangular
eye orbits previously seen in East Asians. Conversely, the
round orbits, large frontal sinuses, and thin cranial bones
seen in some archaic H. sapiens skulls from China repre-
sent the first appearance there of traits that have greater
antiquity in Europe.^25 The movement of these physical
traits has a complex genetic basis that depends upon gene
flow among populations.
Not only is such gene flow consistent with the remark-
able tendency humans have to “swap genes” between pop-
ulations, even in the face of cultural barriers, but it is also
consistent with the tendency of other primates to produce
hybrids when two subspecies (and sometimes even spe-
cies) come into contact.^26 Moreover, without such gene
flow, evolution inevitably would have resulted in the ap-
pearance of multiple species of modern humans, some-
thing that clearly has not happened. In fact, the low level
of genetic differentiation among modern human popula-
tions can be explained easily as a consequence of high lev-
els of gene flow.^27Race and Human Evolution
The Neandertal question can be viewed as more than sim-
ply a fascinating discussion about interpreting the fossil
evidence. It raises fundamental issues about the relation-
ship between biological and cultural variation. Can a series
of biological features indicate particular cultural abilities?
As we examined the fossil record throughout this
chapter and others, we made inferences about the cultural
capabilities of our ancestors based on biological features in
combination with archaeological features. The increased
brain size of Homo habilis noted around 2.5 million years
ago supported the notion that these ancestors were capa-
ble of more complex cultural activities than australopith-
ecines, including the manufacture of stone tools. When we
get closer to the present, can we make the same kinds of
assumptions? Can we say that only the anatomically mod-
ern humans, with high foreheads and reduced brow ridges,
and not archaic Homo sapiens, even with their modern-
sized brains, were capable of making sophisticated tools
and representational art?Neandertal norms, though slightly closer to the Nean-
dertals.^21 Nor is the dentition functionally distinguish-
able when Qafzeh and Neandertal are compared.^22
While skeletons from Skhul, a site on Mount Carmel
of the same period, are similar to those from Qafzeh, they
were also part of a population whose continuous range of
variation included individuals with markedly Neandertal
characteristics. Furthermore, the idea of two distinctly
different but coexisting populations receives no support
from the archaeological evidence. Individuals living at
Skhul and Qafzeh were making and using the same Mous-
terian tools as those at Kebara and Shanidar, a fact that
belies biologically distinct groups having different cultural
abilities.
The examination of sites continuously inhabited
throughout the Upper Pleistocene provides no signifi-
cant evidence for behavioral differences between Middle
Paleolithic and early Upper Paleolithic at these sites. For
example, the Upper Paleolithic peoples who used Kebara
Cave continued to live in exactly the same way as their
Neandertal predecessors: They procured the same foods,
processed them in the same way, used similar hearths, and
disposed of their trash in the same way. The only evident
difference is that the Neandertals did not use small stones
or cobbles to bank their fires for warmth as did their Up-
per Paleolithic successors.^23
Nevertheless, by 28,000 years ago, many of the extreme
anatomical features seen in archaic groups like Neander-
tals seem to disappear from the fossil record in Europe and
Southwest Asia. Instead, people with higher foreheads,
smoother brow ridges, and distinct chins seemed to have
Europe more or less to themselves. However, an examina-
tion of the full range of individual human variation across
the globe and into the present reveals contemporary hu-
mans with skulls not meeting the anatomical definition of
modernity proposed in the standard evolutionary argu-
ments.^24 Similarly, many Neandertal features can be seen
in living people today such as the occipital buns men-
tioned earlier. As is typical in human populations, con-
temporary peoples and Upper Paleolithic peoples exhibit
considerable physical variability.
It is impossible to know just how much gene flow took
place among ancient human populations, but that some
took place is consistent with the sudden appearance of
novel traits in one region later than their appearance else-
where. For example, some Upper Paleolithic remains from
(^21) Corruccini, R. S. (1992). Metrical reconsideration of the Skhul IV and IX
and Border Cave I crania in the context of modern human origins. Ameri-
can Journal of Physical Anthropology 87, 433–445.
(^22) Brace, C. L. (2000). Evolution in an anthropological view (p. 206). Walnut
Creek, CA: Altamira.
(^23) Corruccini, p. 436.
(^24) Wolpoff & Caspari.
(^25) Pope, pp. 287–288.
(^26) Simons, E. L. (1989). Human origins. Science 245, 1349.
(^27) Relethford, J. H., & Harpending, H. C. (1994). Craniometric variation,
genetic theory, and modern human origins. American Journal of Physical
Anthropology 95, 265.