Collaborative Research: Determinants of male reproductive success in natural spawns

提案OCE 0117623 PI-保罗罗森，缅因大学标题：合作研究：男性生殖成功的决定因素在自然spawns.Summary：这项建议是以前的工作，旨在了解生殖生物学的影响，生活史进化模式的殖民海洋被囊动物，Botryllus schlosseri的延伸。 该项目将测试五个假设的因素，可能会决定男性生殖成功的自然产卵的殖民地无脊椎动物。 这五个假设的具体目的是探讨精子释放的时间，配偶的相关性，人口密度，并分配到男性功能的受精成功的领域和实验种群的葡萄球菌的影响。 以前的工作表明，受精可以产生一个有活力的胚胎的时间窗口很窄，并且可能存在配子不相容系统。 此外，精子通常是附近殖民地的产物;群体在精子生产方面表现出变异，当精子竞争发生时，高水平的精子生产只会增加局部的繁殖成功率。这一初步信息表明，自然群体中的雄性繁殖成功率是一个复杂的函数，与其他群体的繁殖周期有关的时间，配子相容性，精子生产，拟议的研究将包括实地和实验室研究，初步工作的重点是最大限度地提高一套9个多态性微卫星位点的信息产量。 这些遗传标记，然后将被用来分析自然产卵的父子关系，并测试一系列的五个假设的男性生殖成功的决定因素。

Proposal OCE 0117623PI - Paul Rawson, University of MaineTitle: Collaborative Research: Determinants of male reproductive success in natural spawns.Summary: This proposal is an extension of previous work aimed at understanding the effects of reproductive biology on patterns of life history evolution in a colonial marine tunicate, Botryllus schlosseri. The project will test five hypotheses about factors that may determine male reproductive success in natural spawns of this colonial invertebrate. The five hypotheses specifically aim to explore the effects of timing of sperm release, relatedness of mates, population density, and allocation to male function on fertilization success in field and experimental populations of Botryllus. Previous work has shown that there is a narrow temporal window in which fertilization can result in a viable embryo, and there may be a gametic incompatibility system. Furthermore, fertilizing sperm are generally the product of nearby colonies; colonies exhibit variation in sperm production, and high levels of sperm production only increase local reproductive success when sperm competition occurs.This preliminary information suggests that male reproductive success in natural populations is a complex function of timing relative to the reproductive cycles of other colonies, gametic compatibility, sperm production, and population density.The proposed research will consist of field and laboratory studies, with preliminary work focused to maximize the information yield of a suite of nine polymorphic microsatellite loci. These genetic markers will then be used to assay paternity in natural spawns and test the series of five hypotheses about the determinants of male reproductive success.