(snip) Most scholars now agree that hunters—more than climate change or a mystery epidemic—are what doomed the mammoths. Whatever the cause, by 11,000 years ago the king of the Pleistocene was a goner. (snip) If a group of devotees has its way, this shaggy ice-age mascot—and a host of other bygone megafauna besides—may yet walk again. (snip) The scientists, in other words, had managed to assemble half the woolly-mammoth genome; they claimed that in three years they could finish the job. That would put scientists within striking distance of an even greater feat: repopulating the earth with creatures that vanished...