Dissertation Research: Evolvability of Sensory Systems in the Bluefin Killifish, Lucania goodei

Travis0073896这个项目将辨别蓝鳍剑鱼视觉系统进化的不稳定性。雄鸟会表现出几种不同的颜色图案之一。光照条件(如水的清晰度、树木的盖度)可以很好地预测种群内雄性变色体的相对丰度。因为这些颜色模式被用来向雌性发出信号，所以视觉系统可能会在不同的人群中有所不同，因此它减轻了每个人群中男性使用的颜色方案。该项目将量化具有不同光照制度的种群之间视觉生理学的变化模式，以及可归因于遗传、环境及其相互作用的种群内的变异量。实验将检验雄性颜色模式对动物行为的影响，以及视觉生理学对人工选择的反应。这项研究的最终目标是确定自然选择是否可以作用于感觉系统，或者感觉系统是否是不变的(因此，对自然选择起到了约束作用)。这个问题是生物学中许多争论的中心(例如衰老的进化、基因组大小、可塑性)。如果生理学可以很容易地对选择做出反应，就可以预测随着时间的推移种群应该发生什么，而模型由于缺乏遗传变异而几乎不涉及约束。然而，如果生理学是不变的，那么这些约束必须被纳入我们的模型--潜在地导致截然不同的预测。

Travis0073896This project will discern the evolutionary lability of the visual system in the bluefin killifish. Males exhibit one of several different color patterns. Lighting conditions (e.g. water clarity, tree cover) are good predictors of the relative abundance of male color morphs within a population. Because these color patterns are used in signaling females, the visual system might vary among populations so that it mitigates the color schemes used by males in each population. This project will quantify the pattern of variation in vision physiology across populations with different lighting regimes and the amount of variation within populations attributable to genetics, environment, and their interactions. Experiments will be performed which examine the effect of male color patterns on animal behavior and the response of vision physiology to artificial selection. The ultimate objective of this study is to determine whether natural selection can act on sensory systems or whether sensory systems are invariant (and, therefore acts as a constraint to natural selection). This question is central to many debates in biology (e.g. evolution of senescence, genome size, plasticity). If physiology can readily respond to selection, predictions can be made as to what should happen to populations over time with models involving few constraints due to a lack of genetic variation. If, however, physiology is invariant, then these constraints must be incorporated into our models - potentially resulting in drastically different predictions.