The Evolution of Sexual Dimorphism in Recently Established Populations: An Ontogenetic Perspective

140年前，查尔斯·达尔文提出了自然选择进化论。这一理论在解释动植物物种的多样性以及生物与其环境之间错综复杂的契合方面非常成功。对于进化生物学家来说，最大的难题之一是两性二态性的进化——同一物种的雄性和雌性在大小、形状和颜色上的差异。性别二态性的群体分化不能用标准的进化理论来解释。提出的研究将检验成人二态性的变化是男性和女性生长发育（个体发生）变化的结果的假设。为了验证这一观点，研究人员将研究最近建立的一种小型鸣禽家雀（Carpodacus mexicanus）种群的性别特异性生长模式。这将是首次研究生长发育在脊椎动物自然种群两性异形进化中的作用。最终，这项工作将为我们理解雄性和雌性的形态如何进化提供重要的新数据和见解。更一般地说，这些数据将增加我们对入侵物种快速殖民的过程的理解，从而有助于保护工作。

One hundred and forty years ago Charles Darwin proposed the theory of evolution by natural selection. This theory has been remarkably successful in explaining both the diversity of species of plants and animals and the intricate fit between organisms and their environment. One of the great puzzles remaining for evolutionary biologists is the evolution of sexual dimorphism - differences between males and females of the same species in size, shape, and coloration. Divergence of populations in sexual dimorphism cannot be explained by standard evolutionary theory. The research proposed will test the hypothesis that change in dimorphism of adults is the result of changes in the growth and development (ontogeny) of males and females. To test this idea the investigators will study sex-specific growth patterns of recently established populations of the house finch (Carpodacus mexicanus), a small songbird.This will be the first study of the role of growth and development in evolution of sexual dimorphism in natural populations of vertebrates. Ultimately, this work will provide significant new data and insight into our understanding of how the morphologies of males and female evolve. More generally, these data will increase our understanding of the processes that enable rapid colonization by invasive species and, thereby, aid conservation efforts.