Ten Years of Cloning

GOAT PIONEER
Not to be outdone, Chinese researchers are perfecting cloning techniques in the hope of using the procedure to preserve the country's beloved panda species. For practice, they began with more common species, including goats like Yangyang (above). Cloning remains a tricky process; only 2%-5% of the eggs that start out as clones develop into live animals. The good news is that once they survive past the first year, clones like Yangyang, celebrating her sixth birthday, are relatively healthy.

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