Biology Now, 2e

Neanderthal Sex ■ 317

According to the out-of-Africa hypothesis,

anatomically modern humans first evolved

in Africa about 195,000–200,000 years ago

from a unique population of archaic H. sapiens, and

then spread into other continents to live along-

side other hominins (Figure 17.14). Evi dence

from the fossil record indicates that anatomi-

cally modern humans overlapped in time with

H. erectus and Neanderthal populations, yet

remained distinct from them. Neanderthals

and modern humans coexisted in western Asia

for about 80,000 years, and in Europe for some

10,000 years, until modern humans completely

replaced all other Homo populations.

But what happened in that intervening time?

Were modern humans and Neanderthals friendly

neighbors, or were the latter quickly wiped out

by the former?

Archaic H. sapiens bore features intermediate

between those of H. erectus and those of “anatom-

ically modern” H. sapiens—our species—which

arose some 195,000–200,000 years ago. These

ancestors of anatomically modern humans

developed new tools and new ways of making

tools, used new foods, and built complex shel-

ters. (But humans are not the only organisms to

do many of these things; see “Uniquely Human?”

on page 316.)

Early populations of archaic humans eventu-

ally gave rise to both the Neanderthals (who lived

from 300,000 to 28,000 years ago) and us—that

is, anatomically modern humans. There is some

debate as to whether Neanderthals are simply

an odd form of archaic H. sapiens, or their own

distinct species. That question has yet to be

resolved.

40,000 years ago 60,000 years ago

56,000 years ago

13,000

years ago

18,000

years ago

115,000

years ago

200,000

years

ago

200,000

years

ago

Figure 17.14

Anatomically modern humans evolved in Africa

The earliest known archaeological specimens of modern humans (Homo sapiens) come from Africa. The

dates provided give the age of the earliest evidence that anatomically modern humans lived in different

regions of the world. These dates are continually challenged by new fossil evidence that scientists must

then work to confirm.

Q1: What evidence suggests that Neanderthals never lived in Africa?

Q2: How does the hypothesized origin of modern humans (Homo sapiens) differ from the

hypothesized origin of Neanderthals (Homo neanderthalensis)?

Q3: What species of hominins other than the Neanderthals may have commingled with modern

humans?