鸟类合作繁殖现象的理论解释及其视角分析

THE THEORETICAL EXPLANATIONS FOR AVIAN COOPERATIVE BREEDING AND THEIR PERSPECTIVE ANALYSIS

鸟类的合作繁殖是指两个以上的族群成员在繁殖期共同抚育同一窝幼雏的现象。当前,合作繁殖现象的理论解释主要是从帮助者的角度分析其对利益与压力的权衡。这种权衡主要包括三个方面:(1)为最大化自身的广义适合度利益,帮助者大多数选择帮助它们的亲属;(2)为了获取帮助行为本身可能带来的其他可观的利益,帮助者协助其他个体进行育雏;(3)由于受到某些因素的限制,帮助者无法独立繁殖,从而不得不选择帮助其他个体。前两种解释是帮助者在利益诱导下的主动帮助,而后者则是帮助者在受到限制后的被动帮助。然而,这些解释都有其局限性,鸟类合作繁殖行为的研究依然未形成统一的理论框架,亟待进一步的拓展和整合。

Cooperative breeding describes a social system in which more than two individuals participate in raising young at a single nest. Current theoretical explanations on the evolution of cooperative breeding behavior were mainly based on the helpers’ tradeoff between the benefits and costs from helping. The tradeoff including three aspects： firstly, the helpers help close relatives to maximize their inclusive fitness; secondly, helpers help because of the benefits from helping perse; lastly, cooperative breeding behavior occurs usually under certain constraints. The former two imply the active co-operations for certain benefits, while the last was passive helping under some constraints. However, all these explanations have their limitations and cannot be generally applied in more other species, especially in those non-cooperatively breeding species. A unified theoretical framework in the evolution of cooperative breeding is still not formed.