CAREER: Integrating Evolutionary and Mechanistic Investigation of Variation in Cooperation and Life History

合作是许多复杂动物社会的关键组成部分，但即使在紧密结合的群体中，一些个体也比其他个体更合作。我们现在知道，个人可以从几个方面的合作中受益，但合作决策的潜在机制和合作数量的变化仍然不完全清楚。矛尾侏儒鸟提供了一个绝佳的机会来研究为什么个体在合作行为上存在差异，以及合作行为和非合作行为如何共存。这种热带鸟类的雄性与非亲属合作进行协调的求爱表演，但只有占统治地位的阿尔法配偶。一些雄性会长期（6年以上）作为非繁殖的beta，而另一些则会在没有成为beta的情况下成为alpha。高度合作和非合作的雄性都只繁殖一次阿尔法，但平均合作年限的雄性的阿尔法成功率较低。该项目将评估领地质量、遗传变异、表型可塑性和下注对冲策略对贝塔雄性行为的作用。本科生、研究生和博士后学员都将参与美国和巴拿马的实验室和实地工作。这项工作通过以下方式将研究和教育结合起来：(1)为本科生实施一门国际实地课程，将参与长期研究与学生设计的项目结合起来；(2)接收巴拿马REU项目本科生3名；(3)开展4 -6年级拓展活动；(4)发布教育资源，建立相关网络摄像头；(5)在现场建立教育展示，每年接待游客8000- 10000人次。本项目研究了刺尾侏儒鸟合作行为变化的潜在机制。它评估了生态约束的作用，实验量化了领地质量对β行为的影响，并测试了解释破坏性选择发生的三个互补假设：遗传变异性、表型可塑性和不可预测环境中的下注对冲。该项目使用纯种雄性行为史的动物模型来量化合作中的加性遗传变异。通过测量条件、应激反应和端粒（染色体末端的重复核苷酸，作为生理状态的生物指标）之间的关系，研究了个体表型对生活史和合作的影响。对终生繁殖成功率的测量将有助于了解合作者是否减少了终生繁殖产出的差异。本项目将培养1名博士后研究员、至少1名研究生和15名野外、实验室和分析技术方面的研究生。该项目提供了对合作的延迟直接利益的功能和对行为表型的破坏性选择的潜在力量的见解。该研究的所有数据将在佛罗里达州立大学存档，与出版物相关的元数据将在Dryad.org上存档。此外，还将通过史密森尼博物馆的数据储存库访问数据库，该储存库是作为马纳金研究协调网络的一部分开发的。

Cooperation is a key part of many complex animal societies, but even within close-knit groups some individuals cooperate more than others. We now know individuals may benefit from cooperation in several ways, but mechanisms underlying decisions to cooperate and variation in the amount of cooperation remain incompletely understood. The lance-tailed manakin provides an excellent opportunity to investigate why individuals vary in cooperative behavior, and how cooperative and non-cooperative behaviors coexist. Males of this tropical bird cooperate with non-relatives in coordinated courtship displays, but only dominant alphas mate. Some males serve long terms (6+ years) as non-breeding betas, while others become alphas without ever being betas. Both highly cooperative and non-cooperative males breed once alpha, but males cooperating for the average number of years have low alpha success. This project will assess the role of territory quality, genetic variability, phenotypic plasticity and bet-hedging strategies on beta male behavior. Undergraduate and graduate students and postdoctoral trainees will all be involved in lab and field work in the U.S. and Panama. This work integrates research and education by (1) implementing an international field course for undergraduates that combines involvement in long-term research with student-designed projects; (2) hosting three undergraduates for REU projects in Panama; (3) developing outreach exercises for 4th-6th graders; (4) publishing educational resources and establishing an associated webcam; and (5) establishing an educational display on the field site, visited by 8000-10,000 tourists/yr. This project investigates mechanisms underlying behavioral variation in cooperation in the lance-tailed manakin. It assesses the role of ecological constraints, experimentally quantifying effects of territory quality on beta behavior, and tests three complementary hypotheses explaining the occurrence of disruptive selection: genetic variability, phenotypic plasticity, and bet-hedging in unpredictable environments. The project quantifies additive genetic variance in cooperation using animal models on behavioral histories of pedigreed males. Effects of individual phenotype on life history and cooperation are investigated by measuring the relationships of condition, stress responsiveness, and telomeres (repeated nucleotides on chromosome ends, implicated as bioindicators of physiological state). Measures of lifetime siring success will yield insights about whether cooperators reduce variance in lifetime reproductive output. The project will train one postdoctoral researcher, at least one graduate student, and 15 postgraduates in field, laboratory, and analytical techniques. This project provides insight into both the function of cooperation by delayed direct benefits and the forces underlying disruptive selection on behavioral phenotypes. All data from the study will be archived at the Florida State University, and metadata associated with publications will be archived on Dryad.org. Databases will furthermore be accessible through a data repository held at the Smithsonian developed as part of the Manakin Research Coordination Network.