Why Cloning Will Never Be Used on Humans
The photograph of two baby monkeys clinging to each other crisscrossed the world early last year. Not just because the long-tailed macaques, Zhong Zhong and Hua Hua, were adorable, but because they were groundbreaking: They were the first primates ever to have been cloned. No scientist before had managed to make exact replicas of animals so close to us on the tree of life.