Viviparity and Speciation: Testing the Alternatives

胎生和物种形成：测试替代方案

• 批准号: 0089945
• 负责人: Jeanne Zeh
• 金额: $ 27.6万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-01-01 至 2004-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0089945&HistoricalAwards=false
• 关键词: Viviparity; Speciation; Testing; Alternatives

New species arise when populations diverge sufficiently to become reproductively isolated. Is this isolation initiated by barriers to mating and fertilization or by post-fertilization genetic incompatibility? Recent theory suggests that reproductive mode may be a critical factor, with the intimate mother/fetus relationship characteristic of live-bearing (viviparous) species making them far more vulnerable to post-fertilization genetic incompatibility than species that lay eggs. This study will exploit unique reproductive features of a model viviparous invertebrate, the false scorpion Cordylochernes scorpioides, to investigate the role of reproductive mode in speciation. Using population pairs spanning a range of genetic divergence, the research will encompass interpopulation crosses, behavioral experiments, and molecular analyses designed to partition reproductive isolation into mating, gametic, and post-fertilization components to determine the precise sequence through which the various forms of reproductive isolation evolve. This research will represent the first comprehensive study of speciation mechanisms in a viviparous animal and will shed light on one of the most striking but poorly understood patterns in speciation, namely that lineages differ profoundly in the relative rates at which pre- and post-fertilization isolation evolve. An increased understanding of the evolutionary and mechanistic causes of reproductive isolation in live-bearing species promises to contribute not only to speciation theory but also to studies aimed at identifying and preserving biological diversity.

当种群分化到生殖隔离的程度时，就会出现新的物种。这种隔离是由交配和受精的障碍还是受精后的遗传不相容引起的？ 最近的理论表明，生殖模式可能是一个关键因素，与亲密的母亲/胎儿关系的特点活轴承（胎生）的物种，使他们更容易受精后的遗传不相容性比产卵的物种。本研究将利用一种胎生无脊椎动物--假蝎Cordylochernes scorpioides独特的生殖特征，探讨生殖方式在物种形成中的作用。使用跨越一系列遗传分歧的群体对，研究将包括群体间杂交，行为实验和分子分析，旨在将生殖隔离划分为交配，配子和受精后成分，以确定各种形式的生殖隔离进化的精确序列。这项研究将代表胎生动物物种形成机制的第一次全面研究，并将揭示最引人注目但知之甚少的物种形成模式之一，即谱系在受精前和受精后隔离进化的相对速率方面存在深刻差异。增加了解的进化和机制的原因，生殖隔离的活轴承的物种承诺，不仅有助于物种形成理论，而且研究旨在确定和保护生物多样性。