互惠利他行为是生物有机体乃至人类社会普遍存在的一种现象，经典的自然选择学说难以解释生物有机体的这类行为。

Reciprocal altruistic behavior exists not only among organisms but also in the society, but it has been hard to explain the altruistic behavior of organisms to the classical natural selection theory.

youdao

互惠利他行为是生物有机体乃至人类社会普遍存在的一种现象，经典的自然选择学说难以解释生物有机体的这类行为。

Reciprocal altruistic behavior exists not only among organisms but also in the society, but it has been hard to explain the altruistic behavior of organisms to the classical natural selection theory.

youdao