In the frozen vastness of the Siberian taiga just below the
Arctic Circle, the loud chatter of jackhammers and generators
crackles through biting sub-zero air.
At this cold, dark outpost on the edge of the world, a team of
scientists is prospecting not for gold or precious gems but rather
for a treasure from the Ice Age, an intact body of a woolly mammoth
encased in a block of ice.
From its frozen body, researchers hope to extract invaluable
insights about the flora and fauna of a bygone era. More important,
though, they hope to find DNA suitable for cloning - to be used to
revive an extinct species.
It's a groundbreaking test of the basic theory laid out in the
film "Jurassic Park," and, if successful, it could lead to the
revival of many extinct species frozen in Siberian ice.
Much remains to be done. The science of cloning remains extremely
difficult, and the Siberian winter could destroy the work
accomplished so far. Yet many scientists are already questioning the
project's ethical implications, wondering whether humans should undo
"Some people think it shouldn't be done, that it goes against
nature. But mammoths lasted in the Siberian Arctic until 37,000
years ago. At least one theory is that humans made them become
extinct," says Larry Agenbroad, a mammoth expert who is
participating in the expedition. "It would be kind of nice to see if
we can revive them."
Dr. Agenbroad says many species can attribute their extinction at
least in part to the rise of homo sapiens, and therefore it is
partly our responsibility to assist in their revival, if possible.
"We have records of how the last two dodo birds were killed by
humans," he says, adding that modern-day mammoths would not likely
multiply to reach past populations or to cause any major
But there are serious scientific problems to overcome before such
possibilities can even be considered. First, scientists need to
remove intact DNA from flesh, soft tissue, or possibly sperm cells
of the Siberian mammoth. The project could then hinge on how well
the DNA is preserved.
"Was the mammoth frozen quickly enough and deeply enough to
ensure that little damage was done to the DNA?" asks Karl Flessa, a
paleontologist at the University of Arizona in Tucson. "Degraded DNA
or DNA with freezer burn is not likely to be of much use."
How to clone a mammoth
Even with intact DNA, however, cloning the mammoth is far from a
sure thing. Scientists would have to strip the DNA from an egg cell
of an Asian elephant, the closest living relative to a woolly
mammoth. The mammoth DNA would then be injected into this egg cell,
a technique similar to that used to clone mice. But no one has
cloned an elephant, let alone a woolly mammoth. Furthermore, cloning
male mammals has proven difficult.
In addition, elephants are scarce, expensive to keep, and at
times dangerous to handle. "It's a very inconvenient animal to study
because of its size, when you compare that to mice where you can
keep thousands at a university facility," says Jonathan Hill, a
cloning expert at Texas A&M University. "Little work has been done
with elephant eggs."
In their day, mammoths were the largest land mammals on the
planet, weighing more than 10 tons and standing 12 feet or taller.
They first appeared between 3 million and 4 million years ago in sub-
Saharan Africa. …