Biology Now, 2e

(Ben Green) #1

302 ■ CHAPTER 17 Animals and Human Evolution


BIODIVERSITY


twenty-first century, Laura Longo, a curator at
the Civic Natural History Museum of Verona,
Italy, decided to take a second look at a group
of fossils excavated from a rock shelter called
Riparo Mezzena. Riparo Mezzena is nestled
in the Lessini Mountains in northern Italy, a
wide-open landscape speckled with large rocks
and evergreen trees. The region is snowy and
silent in the winter but green and thriving in the
summer, when paleontologists come to work.
In the 1950s, paleontologists had carefully
collected fossils of Neanderthals that lived
around Riparo Mezzena about 35,000 years
ago, late in the history of Neanderthals. But the
fossils had sat at the museum, untouched, for
over 50 years (Figure 17.1). Now, Longo believed,
the fossils could help answer a hotly debated
question about human history: How closely did
modern humans and Neanderthals interact?

Animal Kingdom


Modern humans and Neanderthals lived in
some of the same areas of Europe at the same
times. Because of this proximity, some paleon-
tologists hypothesize that as modern humans
expanded their territory, Neanderthals were

I


n popular culture, Neanderthals are ugly,
hairy cavemen with big brains but no wits.
The first Neanderthal bones were discovered
in Germany in 1856, and since then we’ve culti-
vated an image of our closest extinct human
relatives as hulking brutes who communi-
cated by grunting, walked like chimps, and hit
each other over the head with clubs. Yet, over
the years, paleontologists have dug up fossil-
ized vocal bones, sophisticated tools, and other
evidence suggesting that Neanderthals were
a fairly advanced group—and not as different
from our own species as we once believed.
The big revelation came in 2010, when scien-
tists sequenced the Neanderthal genome and
compared it to the modern human genome:
Humans have some Neanderthal DNA. Our two
species may have been a whole lot closer than we
thought. “There could have been interbreeding
between modern humans and Neanderthals,”
says Silvana Condemi, a researcher at the National
Center for Scientific Research (CNRS) at Aix-
Marseille University in France. “We can imagine
they not only exchanged culture, but exchanged
genes.” That’s right: mounting evidence suggests
that Neanderthals and modern humans had sex.
This story begins where many stories end—
with a pile of bones. In the early years of the

Figure 17.1


Fossil remains
A jawbone like this one was found at the Riparo Mezzena rock shelter in the Lessini Mountains in Italy.
The individual it belonged to lived between 40,000 and 30,000 years ago.
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