为什么黑猩猩会自相残杀?

Chimpanzees kill other chimpanzees, according to a ten-year study conducted in a Uganda national park and released in the journal Current Biology in June, 2010. Primate behavioral ecologist Sylvia Amsler observed groups of male chimps patrolling the edges of their territory and targeting rivals for brutal killings.

2010年6月发表在《当代生物学》杂志上的一项研究表明，黑猩猩会自相残杀，该研究在乌干达国家公园展开，历时十年完成。灵长类动物行为生态学家西尔维亚．阿姆斯勒观察发现雄性黑猩猩会在它们地盘边界巡逻，还会残忍杀害竞争者。

Sylvia Amsler: We’ve known for quite some time, since the 1970’s, that chimpanzees regularly go on territorial boundary patrols looking for members of other chimpanzee communities. And when they find them and are able to isolate individuals, chimpanzees kill these other chimpanzees in these very dramatic episodes of lethal, coalitionary aggression. The question has been why, from an evolutionary perspective, they’re engaging in this behavior.

西尔维亚．阿姆斯勒：早在上世纪70年代我们就知道黑猩猩会定期在自己地盘边界巡逻，搜寻来自其他族群的黑猩猩，一旦找到它们，对它们进行隔离后，就会用非常残忍极端的手段将这些外来的黑猩猩杀死。我们关注的问题是，如何用进化论观点解释黑猩猩的这种行为的动机。

The answer, according to the study, is to increase the chimpanzees’ territory, and therefore their access to food.

这样研究给出的结论是：黑猩猩扩大自己地盘后就能获得更多的食物资源。

Sylvia Amsler: This is not an unnatural, or aberrant behavior in any way, but actually has positive reproductive consequences for the males who do it. So although it seems very brutal, from an evolutionary perspective，they and their mates and their offspring are all going to be more successful as a result of this behavior.

西尔维亚．阿姆斯勒：这算不上是反常或异常行为，实际上这些雄性黑猩猩大开杀戒的行为有利于其自身繁殖后代。故从进化论观点看，虽然这种行为看上去非常残忍，但对它们的配偶及后代都是非常有利的。

Amsler said the group she studied may be more aggressive than normal, possibly because it’s a larger than average population with a high number of adult males.

阿姆斯勒说她研究的黑猩猩群可能比普通黑猩猩群落更具侵略性，可能是因为该群落中的成年雄性黑猩猩数量偏多，超过种群平均水平。