DISSERTATION RESEARCH: Extra-pair behavior and female fitness in the dark-eyed junco (Junco hyemalis)

这个项目从雌性的角度研究鸟类的额外配对交配。这项研究询问，与多只雄性交配的雌性是否直接受益，因为它们产生的后代比只与一只雄性交配的雌性更多，还是间接受益，因为它们产生了更高质量的后代。结论将基于18年来从4000多个个体收集的DNA样本，以及种群动态和繁殖成功的长期记录。被研究的物种，黑眼睛的金丝雀，是一种社会上一夫一妻制的鸣禽。雄性和雌性形成长期的配对关系，共同抚养后代，但大约25%的后代是由社会联系在一起的雄性以外的雄性繁殖的。从雄性S的角度来看，超外交配很容易理解；雄性S如果与多只雌性交配，繁殖成功率会增加。不太清楚的是，为什么女性会参与这种行为，过去的研究也没有解决这个问题。这项研究的持续时间和范围为研究交配模式对雌性终生生殖成功的影响提供了一个独特的机会。结果将阐明具有复杂交配系统的物种进行性别选择的可能性。

This project examines extra-pair mating in birds from the female perspective. The research asks whether females that mate with more than one male benefit directly, by producing more offspring than they would if they mated with just one male, or indirectly, by producing offspring of higher quality. Conclusions will be based on DNA samples collected over 18 years from more than 4000 individuals and on long-term records of population dynamics and reproductive success. The study species, the dark-eyed junco, is a socially monogamous songbird. Males and females form a long-term pair bond and jointly raise offspring, but ~25% of all offspring are sired by a male other than the socially bonded male. Extra-pair mating is easily understood from the male?s perspective; a male?s reproductive success will increase if he mates with multiple females. Less clear is why females participate in this behavior, and past research has not resolved the question. The duration and scope of this study provide a unique opportunity to examine the influence of mating patterns on lifetime reproductive success of females. Results will clarify the potential for sexual selection in a species with a complex mating system.