Indivdual reproductive decisions: Behavioral mechanisms and adaptive significance

该奖项是根据2009年美国复苏和再投资法案(公法111-5)资助的。了解产生和维持基因变异的过程是现代生物学的一个重要目标。在许多可能影响遗传变异的行为过程中，很少有像生育决定这样直接影响的。生殖伴侣的选择决定了哪些遗传信息会在几代人之间传播，并影响后代的健康和生殖成功。直到最近，人们才意识到，雌性个体在生殖决定上可能会有很大的差异，这种差异对于维持种群遗传变异和多样化的雄性求偶行为至关重要。这项研究调查了一种觅食的雀形目鸟类--长尾鸟(Chiroxiphia Lanceolata)--的雌性生殖决定。在LEK系统中，雌性主动评估并从展示的雄性中进行选择，但除了从它们选择的伴侣那里获得基因外，什么也得不到(没有父亲的照顾，雄性也不控制食物或筑巢资源的获取)。遗传亲子关系分析显示，雌性矛尾假人在不同的繁殖季节经常改变伴侣的选择，即使之前喜欢的伴侣仍然存在，并与其他雌性成功繁殖。雌性对相同的雄性进行评估，但做出不同的生殖决定。该项目结合了对行为的现场观察、对女性的自动无线电跟踪以及对亲子关系和变异的遗传分析，以(1)表征导致伴侣偏好变化的行为机制；(2)确定与这种变化相关的女性特征(例如，年龄、条件和生育经验)；以及(3)测试关于不同生殖决定对女性个体的益处的假设。这项工作将提供亟需的经验证据，以检验可变的雌性生殖选择影响野生种群性别选择过程的想法。此外，该项目将通过向美国和巴拿马的普通公众进行外联演示，为研究生和本科生提供培训机会，取得对大学教学有用的结果，并提供教育效益。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Understanding the processes that produce and maintain genetic variation is a critical goal of modern biology. Of the many behavioral processes that may influence genetic variation, few are as directly influential as reproductive decisions. Choice of a reproductive partner determines which genetic information is transmitted across generations and affects offspring health and reproductive success. Only recently has it been appreciated that individual females may vary considerably in their reproductive decisions and that this variability can be critical in maintaining population genetic variation and diverse male courtship behaviors. This study investigates female reproductive decisions in a lekking passerine bird, the lance-tailed manakin (Chiroxiphia lanceolata). In lek systems, females actively assess and choose from among displaying males, but receive nothing but genes from their chosen partner (there is no paternal care, and males do not control access to food or nesting resources). Genetic paternity analyses have revealed that female lance-tailed manakins frequently change their choice of partners in different breeding seasons, even when previously-favored partners are still available and reproduce successfully with other females. Females assess the same males, but make different reproductive decisions. This project combines field observations of behavior, automated radio-tracking of females, and genetic analyses of paternity and variation to (1) characterize the behavioral mechanisms that generate variation in partner preferences; (2) identify female characteristics associated with this variation (e.g. age, condition, and reproductive experience); and (3) test hypotheses about the benefits of variable reproductive decisions to individual females. This work will provide much-needed empirical evidence to test the idea that variable female reproductive choices influence the process of sexual selection in wild populations. Furthermore, the project will provide training opportunities for graduate and undergraduate students, results useful in university-level teaching, and educational benefits through outreach presentations to the general public in the US and Panama.