送交者: mangolasi 于 2006-3-03, 09:53:08:
“ To reach a food tray from behind bars, a chimpanzee had to pull on two ends of a rope threaded through metal loops on the tray. If the chimpanzee simply pulled on one end, the rope would slip the loop. If, however, the chimpanzee unlocked the door to an adjacent room, released a fellow chimp, and cooperated with it to pull on both ends of the rope at the same time, both would be rewarded with the food on the tray.”
“When the rope ends were placed close enough together that a single chimp could accomplish the task, the subjects rarely enlisted aid. But when they required help--and were given a choice between potential collaborators--the chimps quickly learned to choose partners better at cooperation.”
http://www.scientificamerican.com/article.cfm?chanID=sa003&articleID=0008218C-6B99-1407-AB9983414B7F0000