neatly contained in a wooden crate on the con-
crete floor of the warehouse, a woman and child
are buried together.
When researchers first analyzed the DNA
from some of these graves, they expected the
Corded Ware folk would be closely related to
Neolithic farmers. Instead, their DNA contained
distinctive genes that were new to Europe at
the time—but are detectable now in just about
every modern European population. Many
Corded Ware people turned out to be more
closely related to Native Americans than to
Neolithic European farmers. That deepened
the mystery of who they were.ONE BRIGHT OCTOBER MORNING near the Ser-
bian town of Žabalj, Polish archaeologist Piotr
Włodarczak and his colleagues steer their
pickup toward a mound erected 4,700 years ago.
On the plains flanking the Danube, mounds like
this one, a hundred feet across and 10 feet high,
provide the only topography. It would have
taken weeks or months for prehistoric humans
to build each one. It took Włodarczak’s team
weeks of digging with a backhoe and shovels
to remove the top of the mound.
Standing on it now, he peels back a tarp to
reveal what’s underneath: a rectangular cham-
ber containing the skeleton of a chieftain, lying
on his back with his knees bent. Impressions
from the reed mats and wood beams that formed
the roof of his tomb are still clear in the dark,
hard-packed earth.
“It’s a change of burial customs around 2800
B.C.,” Włodarczak says, crouching over the skele-
ton. “People erected mounds on a massive scale,
accenting the individuality of people, accent-
ing the role of men, accenting weapons. That’s
something new in Europe.”
It was not new 800 miles to the east, however.
On what are now the steppes of southern Russia
and eastern Ukraine, a group of nomads calledthe Yamnaya, some of the first people in the
world to ride horses, had mastered the wheel
and were building wagons and following herds
of cattle across the grasslands. They built few
permanent settlements. But they buried their
most prominent men with bronze and silver
ornaments in mighty grave mounds that still
dot the steppes.
By 2800 B.C., archaeological excavations show,
the Yamnaya had begun moving west, proba-
bly looking for greener pastures. Włodarczak’s
mound near Žabalj is the westernmost Yamnaya
grave found so far. But genetic evidence, Reich
and others say, shows that many Corded Ware
people were, to a large extent, their
descendants. Like those Corded Ware
skeletons, the Yamnaya shared dis-
tant kinship with Native Americans—
whose ancestors hailed from farther
east, in Siberia.
Within a few centuries, other peo-
ple with a significant amount of
Yamnaya DNA had spread as far as
the British Isles. In Britain and some
other places, hardly any of the farmers
who already lived in Europe survived
the onslaught from the east. In what is now
Germany, “there’s a 70 percent to possibly 100
percent replacement of the local population,”
Reich says. “Something very dramatic happens
4,500 years ago.”
Until then, farmers had been thriving in
Europe for millennia. They had settled from Bul-
garia all the way to Ireland, often in complex vil-
lages that housed hundreds or even thousands
of people. Volker Heyd, an archaeologist at the
University of Helsinki, Finland, estimates there
were as many as seven million people in Europe
in 3000 B.C. In Britain, Neolithic people were
constructing Stonehenge.
To many archaeologists, the idea that a bunch
of nomads could replace such an established
civilization within a few centuries has seemed
implausible. “How the hell would these pasto-
ral, decentralized groups overthrow grounded
Neolithic society, even if they had horses and
were good warriors?” asks Kristian Kristiansen,
an archaeologist at the University of Gothenburg
in Sweden.
A clue comes from the teeth of 101 people liv-
ing on the steppes and farther west in Europe
around the time that the Yamnaya’s westward
migration began. In seven of the samples,Third WaveOUT OF THE STEPPE
108 NATIONAL GEOGRAPHIC