Pandas Prepare for Risky Duty

Four panda bears bred in captivity in China will soon be set free in a bid to save their species from extinction. But first, they've got to toughen up. Scientists at the nation's biggest panda breeding center are preparing to release two males and two females into the wild, and they're trying to give the bears street smarts of a sort—how to sense danger and fend off attacks, the Times reports.

The scientists say they've learned a lesson from last year, when they set a male free only to have him killed by his wild cousins when he encroached on their territory. The experiment is risky, but scientists say they need to expand the gene pool of the 1,600 or so pandas in the wild if the species is to survive. (More panda stories.)