Comparative Social Biology of Sponge-Dwelling Snapping Shrimp (Synalpheus)

海绵栖息地捕捉的比较社会生物学埃米特·达菲海洋科学学院威廉和玛丽海洋学院的特点是大多数成员牺牲个体繁殖的合作群体，长期以来一直是行为和进化生态学的基本悖论。根据汉密尔顿规则，社会行为可以理解为通过相互作用者的遗传相关性来应对环境施加的挑战的解决方案。因此，对社会进化的充分理解需要考虑群体成员之间的遗传关系，对种群的基本生态制约，以及评估它们相互作用的进化后果的一些手段。这一建议使用互补的遗传、行为和比较方法来评估亲缘结构和社会生物学之间的相互作用及其一些宏观进化后果，以促进物种丰富和社会多样性的海绵栖息虾(Synalpheus)的社会进化，Synalpheus是一种稀有动物群体，在密切相关的物种之间反复出现共生现象。该项目有两个主要目标：(1)评估繁殖系统和随之而来的群体遗传结构对两个独立进化的、在人口统计学上存在差异的对虾物种Synalpheus regalis和S.chacei的行为动态和极端生殖偏差的维持的影响。这将通过在8个微卫星座位上对野外收集的每个物种的群体中的个体进行基因分型，并在实验室通过实验评估圈养群体中个体之间的冲突和合作水平来实现。这项研究将描述群体内个体之间的亲缘关系、攻击性优势、交配成功和亲子关系的分布，以及群体内与群体间的亲缘关系。(2)在最近完成的海绵栖息支系的系统发育重建的基础上，通过利用联会菌属物种之间的社会多样性，将在比较框架内探讨这些社会动态的较长期进化后果。通过对群居昆虫的理论和经验研究，系统学上独立的对比将检验群居大小、生殖偏差和种姓分化之间的联系。这项研究将提供一个新的窗口，在一个独特的，社会多样化的非昆虫无脊椎动物分支的起源，适应意义，和宏观进化的后果，并将有助于评估在广泛的分类水平的理论的普遍性，高级动物社会的进化主要基于社会昆虫的数据。

COMPARATIVE SOCIOBIOLOGY OF SPONGE-DWELLING SNAPPING SHRIMPSJ. Emmett DuffySchool of Marine ScienceThe College of William and Mary Eusociality, characterized by cooperative colonies in which most members sacrifice individual reproduction, has long presented a fundamental paradox for behavioral and evolutionary ecology. According to Hamilton's rule, social behaviors can be understood as solutions to challenges imposed by the environment mediated through the genetic relatedness of interactants. A full understanding of social evolution thus entails an accounting of the genetic relationships among group members, the basic ecological constraints on populations, and some means of assessing the evolutionary consequences of their interplay. This proposal employs complementary genetic, behavioral, and comparative approaches to assess the interplay between kin structure and social biology, and some of its macroevolutionary consequences, in fostering social evolution in the species-rich and socially diverse sponge-dwelling shrimps (Synalpheus), one of the rare animal groups in which eusociality has arisen repeatedly among closely related species. The project has two principal objectives:(1) Assess the influence of breeding system, and consequent genetic structure of colonies, on behavioral dynamics and the maintenance of extreme reproductive skew in two independently evolved, and demographically divergent, eusocial shrimp species Synalpheus regalis and S. chacei. This will be accomplished by genotyping individuals from field-collected colonies of each species at eight microsatellite loci, and experimentally assessing levels of conflict and cooperation among individuals in captive colonies in the laboratory. This research will characterize the distributions of relatedness, aggressive dominance, mating success, and parentage among individuals within colonies, and of relatedness within vs. among colonies. (2) The longer-term evolutionary consequences of these social dynamics will be approached in a comparative framework by exploiting the social diversity among species of Synalpheus, building on the recently completed phylogenetic reconstruction of the sponge-dwelling clade. Phylogenetically independent contrasts will test the association, predicted by theory and empirical studies of social insects, among colony size, reproductive skew, and caste differentiation. This research will provide a new window on the origin, adaptive significance, and macroevolutionary consequences of eusociality in a unique, socially diverse clade of non-insect invertebrates, and will contribute to evaluating the generality at a broad taxonomic level of theories for the evolution of advanced animal societies based primarily on data from social insects.