Avian Polyandry: Life-History Strategies in a Model System

摘要本研究的最终目的是了解男女行为差异这一极其普遍的生物学现象。进化理论和实验证据表明，投入在照顾后代上的时间和精力可能会强烈影响两性的选择。这种差异可能有利于男性和女性表现出不同的行为。在那些表现出亲代照顾的动物物种中，雌性通常提供大部分这样的照顾，让雄性自由地通过额外的交配来提高它们的生物成功率。在这种情况下，自然选择可能倾向于在两性中发展出不同的策略。这导致了一些假设：为什么两性在互动中经常扮演不同的角色，为什么伴侣之间的行为冲突如此普遍，以及在这种冲突中可以预期什么样的行为解决方式。通过研究照顾责任与“规范”相反的物种，这些观点可以受到特别关键的检验。埃姆伦博士正在研究这种物种的一个极端例子，在这种物种中，雄性负责所有的后代照顾，雌性通过拥有多个雄性伴侣来提高自己的生物成功率。本研究将仔细记录男性和女性所采用的行为角色以及不同角色表达的背景。这将增加对为什么特定形式的行为受到一种性别的偏爱，以及这种行为的表达在进化中的作用的科学理解。

9317988 Emlen ABSTRACT This research is ultimately concerned with understanding behavioral differences between females and males, an extremely widespread biological phenomenon. Evolutionary theory and experimental evidence suggest that the amount of time and energy invested in the care-taking of offspring may strongly influence the options available to each sex. Such differences may have favored the expression of different behaviors in males and females. Among those animal species that show parental care, females usually provide the bulk of such care, leaving males free to increase their biological success through additional matings. Under such conditions, natural selection might be expected to have favored the development of different strategies in the two sexes. This has led to hypotheses about why the sexes often adopt different roles during interactions, why behavioral conflict between mates is so common, and what forms of behavioral resolution can be expected in such conflicts. These ideas can be subjected to particularly critical test by studying species in which care-taking responsibilities are reversed from the "norm". Dr. Emlen is studying an extreme example of such a species, in which males look after all offspring care and females increase their biological success by having multiple male mates. This research will carefully document the behavioral roles adopted by males and females and the contexts in which different roles are expressed. This will increase scientific understanding of why particular forms of behavior are favored by one sex over the other, and of the evolutionary role of the expression of such behaviors.