Major Paleolithic Trends 225The picture currently emerging, then, is of people, who
may not have looked like modern Native Americans, arriving
by boats or rafts and spreading southward and eastward over
time. In fact, contact back and forth between North America
and Siberia never stopped. In all probability, it became more
common as the glaciers melted away. As a consequence,
through gene flow as well as later arrivals of people from
Asia, people living in the Americas came to have the broad
faces, prominent cheekbones, and round cranial vaults that
tend to characterize the skulls of many Native Americans
today. Still, Native Americans, like all human populations,
are physically variable. The Kennewick Man controversy de-
scribed in Chapter 5 illustrates the complexities of establish-
ing ethnic identity based on the shape of the skull. In order
to trace the history of the peopling of the Americas, anthro-
pologists must combine archaeological, linguistic, and cul-
tural information with evidence of biological variation.
Although the earliest technologies in the Americas
remain poorly known, they gave rise in North America,
about 12,000 years ago, to the distinctive fluted spear points
of Paleoindian hunters of big game, such as mammoths,
mastodons, caribou, and now extinct forms of bison. Fluted
points are finely made, with large channel flakes removed
from one or both surfaces. This thinned section was in-
serted into the notched end of a spear shaft for a sturdy haft.
Fluted points are found from the Atlantic seaboard to the
Pacific Coast, and from Alaska down into Panama. The effi-
ciency of the hunters who made and used these points may
have hastened the extinction of the mammoth and other
large Pleistocene mammals. By driving large numbers of
animals over cliffs, they killed many more than they could
possibly use, thus wasting huge amounts of meat.
Upper Paleolithic peoples in Australia and the Americas,
like their counterparts in Africa and Eurasia, possessed
sophisticated technology that was efficient and appropri-
ate for the environments they inhabited. As in other parts
of the world, when a technological innovation such as the
fluted points begins, this technology is rapidly disseminated
among the people inhabiting the region.Major Paleolithic Trends
As we look at the larger picture, since the time the genus
Homo appeared, evolving humans came to rely increas-
ingly on cultural, as opposed to biological, adaptation. To
handle environmental challenges, evolving humans de-
veloped appropriate tools, clothes, shelter, use of fire, and
so forth rather than relying upon biological adaptation
of the human organism. This was true whether humanpopulations spread from Siberia to Alaska, linguist Johanna
Nichols suggests that the first people to arrive in North
America did so by 20,000 years ago. She bases this estimate
on the time it took various other languages to spread from
their homelands—including Eskimo languages in the Arctic
and Athabaskan languages from interior western Canada to
New Mexico and Arizona (Navajo). Nichols’s conclusion is
that it would have taken at least 7,000 years for people to
reach south-central Chile.^42 Others suggest people arrived
in the Americas closer to 30,000 years ago or even earlier.
A recent genetic study using mtDNA indicates that
two groups of migrants crossed Beringia between 15,000
and 17,000 years ago but then took different paths. One
group traveled down the Pacific Coast and the other down
the center of the continent. While the dates generated
in this study are as early as others have suggested, these
findings support the notion that distinct language groups
made separate migrations.
(^42) The first Americans, ca. 20,000. (1998). Discover 19 (6), 24.
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Figure 9.10 The Arctic conditions and glaciers in northeastern
Asia and northwestern North America provided opportunity
and challenges for ancient people spreading to the Americas.
On the one hand, the Arctic conditions provided a land bridge
(Beringia) between the continents, but on the other hand, these
harsh environmental conditions posed considerable challenges
to humans. Ancient people may have also come to the Americas
by sea. Once in North America, glaciers spanning a good portion
of the continent determined the areas open to habitation.
Paleoindians The earliest inhabitants of North America.