He and, eventually, Nikita fenced in wild horses
and later trucked in yaks and sheep from Lake
Baikal. This past spring Nikita hauled in 12
bison from Denmark, traveling 9,000 miles
across Russia by truck and barge. In 2018 the
Zimovs joined forces with Harvard Univer-
sity geneticist George Church, who thinks he
essentially can clone a mammoth. The hope is
that one day those now extinct beasts will be
stomping around Pleistocene Park, thriving in
the Anthropocene.
The park is the ultimate test of Sergey Zimov’s
hypothesis—and, he hopes, a hedge against
future climate change. Grasslands, especially
when snow covered, reflect more sunlight than
does dark forest. Grazing animals tamp down
deep snow, allowing heat to escape the soil. Both
things cool the land. If wildlife could restore
grasslands, it would slow permafrost thaw and
thus climate change. To make a real difference,
though, you’d need to unleash thousands of
zoos’ worth of animals across millions of acres
of the Arctic.
The Zimovs say the evidence from their
36,000-acre park is promising. Even with only
about a hundred animals, the park’s grasslands98 NATIONAL GEOGRAPHIC