Dissertation Research: Did predation Drive Micro- and Macroevolutionary Diversification in Mosquitofish?

该项目将测试的假设，不同的自然选择之间的捕食者政权驱动了适应性分化种群内的物种（微观进化）和物种之间的属（宏观进化）。使用生物力学方法，该研究将测试预测不同捕食者制度中的自然选择如何有利于食蚊鱼属（食蚊鱼）的不同体型和游泳能力。 该项目将使用比较分析来评估与低捕食和高捕食环境殖民化相关的体形、长时间游泳性能和快速启动游泳性能的进化变化。该研究将进一步研究性状差异的遗传基础，并测试物种内部和物种之间形态-性能关系的生物力学预测（揭示体型和游泳之间的因果关系）。本研究的方法论应揭示自然选择和随机遗传漂变在微观和宏观进化尺度上的相对重要性，定量研究了进化生物学中的一个基本问题--驱动微观进化分歧的过程是否可以解释宏观进化模式。这项工作应提供一个重要的贡献，适应性进化的研究，特别是捕食在进化多样化的作用和效用的生物力学方法在理解适应性分歧的功能基础。该项目将进一步帮助培训几名学生进行实验室和实地研究，并向科学界和广大公众广泛传播。

This project will test the hypothesis that divergent natural selection between predator regimes has driven adaptive divergence between populations within a species (microevolution) and between species within a genus (macroevolution). Using a biomechanical approach, the study will test predictions of how natural selection in different predator regimes should favor different body forms and swimming capabilities in livebearing fish of the genus Gambusia (mosquitofishes). The project will use comparative analyses to assess evolutionary changes in body shape, prolonged swimming performance, and fast-start swimming performance associated with colonization of low- and high-predation environments. The study will further examine the genetic basis of trait differences, and test biomechanical predictions of morphology-performance relationships within and between species (revealing the causal connections between body form and swimming). The methodological approach of the study should reveal the relative importance of natural selection and random genetic drift in the evolution of traits at the micro- and macroevolutionary scales.The study quantitatively examines a fundamental question in evolutionary biology-whether processes driving microevolutionary divergence can explain macroevolutionary patterns. The work should provide an important contribution to the study of adaptive evolution, particularly the role of predation in evolutionary diversification and the utility of a biomechanical approach in understanding the functional basis of adaptive divergence. The project will further help train several students in both laboratory- and field-based research, and be widely disseminated to the scientific community, as well as the broader public.