Dissertation Research: Cooperation and the Covariance between Genetic Monogamy and Limited Dispersal

论文研究：遗传一夫一妻制与有限扩散之间的合作与协变

• 批准号: 1601425
• 负责人: David Westneat
• 金额: $ 1.9万
• 依托单位: University of Kentucky Research Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-05-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1601425&HistoricalAwards=false
• 关键词: Dissertation; Research; Cooperation; Covariance; between

Many animals, including humans, live in extended family groups where both parents and mature offspring share the responsibility of caring for young. This type of social system, called cooperative breeding, is frequently associated with monogamy across a diversity of animal groups. This association is thought to result from the fact that helpers in monogamous groups share on average 50% of their genes with their full siblings - the same proportion they share with their own offspring. Therefore, from a gene's eye view, helping can be as good a strategy as reproducing independently when helpers can assist in rearing full siblings. Although staying near home to help can be beneficial in some circumstances, the benefits of cooperating could be reduced or even cancelled out if helpers find themselves competing with close relatives for resources when they do not disperse from the area where they were born. This project investigates the contexts in which cooperation and competition occur to determine if animals can balance these costs and benefits through dispersal behavior. This proposal also tests a novel alternative explanation for the observed association between monogamy and cooperation, asking whether this relationship could be due to environmental factors that similarly influence both mate fidelity and helping behavior. The role of sibling relatedness in the evolution of cooperation is of major interest in the field of behavioral evolution, and the studies proposed here could have profound influences on our understanding of family-based cooperative societies, such as our own. The project will also provide multiple training opportunities for graduate and undergraduate students in a range of modern scientific skills, including the use of the most cutting edge DNA sequencing techniques. The work will be shared with the public through a community science festival and scientific illustration classes.This research investigates the relationship between mating systems and social systems using cooperative bess beetles as a model organism. First, fine-scale population structure will be assessed to test the hypothesis that beetles cooperate locally within their highly related family group before dispersing to compete globally with unrelated individuals, allowing them to avoid the costs of competing with kin while maximizing the benefits of cooperating with relatives. The second objective in this study will test the novel hypothesis that certain environments may favor both monogamy and cooperation simultaneously, leading to a correlation between mating and social system that is consequential rather than causal. Conceptually, this hypothesis suggests that the terms in Hamilton's Rule (rB-C0) may covary in certain environments. Specifically, this study will test whether a single ecological factor, low resource density, reduces the costs (C) of helping (by increasing the costs of dispersal) while simultaneously increasing the relatedness between helpers and their siblings (r) by reducing extra-pair paternity. To assess this possibility, paternity and dispersal will be investigated in response to resource density in both natural and experimental populations of bess beetles. The results of this study could suggest that the terms in Hamilton?s Rule are not modular, but rather covary under certain conditions, changing the way we understand both the correlated evolution of social and mating systems as well as the association between relatedness and cooperation.

包括人类在内的许多动物都生活在大家庭中，父母和成熟的后代共同承担照顾后代的责任。这种类型的社会系统，称为合作育种，通常与多种动物群体的一夫一妻制有关。这种关联被认为是由于一夫一妻制群体中的帮手与他们的同胞兄弟姐妹平均共享50%的基因-与他们与自己的后代共享的比例相同。因此，从基因的角度来看，当帮助者可以帮助抚养完整的兄弟姐妹时，帮助可以是与独立繁殖一样好的策略。虽然在某些情况下，留在家附近帮忙可能是有益的，但如果帮助者发现自己在不离开出生地的情况下与近亲竞争资源，合作的好处可能会减少，甚至被抵消。该项目调查了合作和竞争发生的背景，以确定动物是否可以通过分散行为平衡这些成本和收益。这个提议也测试了一个新的替代解释观察到的一夫一妻制和合作之间的关联，问这种关系是否可能是由于环境因素，同样影响配偶的忠诚和帮助行为。兄弟姐妹关系在合作进化中的作用是行为进化领域的主要兴趣，这里提出的研究可能会对我们理解以家庭为基础的合作社会产生深远的影响，比如我们自己。该项目还将为研究生和本科生提供多种现代科学技能培训机会，包括使用最先进的DNA测序技术。这项工作将通过社区科学节和科学插图课程与公众分享。本研究以合作的碧甲虫为模式生物，探讨交配系统和社会系统之间的关系。首先，精细规模的人口结构将进行评估，以测试的假设，甲虫合作本地高度相关的家庭群体之前，分散到全球竞争与无关的个人，使他们能够避免与亲属竞争的成本，同时最大限度地提高与亲属合作的好处。本研究的第二个目的是检验新的假设，即某些环境可能同时有利于一夫一妻制和合作，导致交配和社会系统之间的相关性是因果关系而不是因果关系。从概念上讲，这一假设表明，在汉密尔顿的规则（rB-C 0）的条款可能在某些环境中的协变。具体来说，这项研究将测试是否一个单一的生态因素，低资源密度，降低成本（C）的帮助（通过增加分散成本），同时增加之间的相关性的帮助者和他们的兄弟姐妹（r）通过减少额外的对父子关系。为了评估这种可能性，父权和传播将调查在自然和实验种群的碧甲虫的资源密度。这项研究的结果可能表明，在汉密尔顿？的规则不是模块化的，而是在一定条件下的协变，改变了我们理解社会和交配系统的相关进化以及相关性和合作之间的关联的方式。