Ecological and Geographic Scaling of Bioenergetic Adaptation

自然种群遗传变异的空间模式可以为生物适应其栖息地的方式提供重要线索。但模式本身可以由不同的原因产生(例如，当地条件的自然选择、具有不同特征的生物的迁徙模式、历史文物等)。这项研究试图解释一种有趣的变异模式的原因，在这种模式中，尽管在栖息地之间进行了广泛的迁徙，但生活在邻近栖息地类型的个体群体之间的相似性低于生活在数百公里外类似栖息地类型的个体群体的相似性。这项研究将集中在昆虫属Colias，并将重点放在支持昆虫在野外飞行的能量处理系统中的关键酶-磷酸葡萄糖异构酶(PGI)的变异。之前在野生Colias的选择和能量学方面的广泛工作，以及这种昆虫在山地地区的分布模式，使其成为解决这些问题的理想系统。研究人员将测试对这一现象的几种可选的看似合理的解释，研究生物特征地理变异的多种潜在原因。这些测试将包括研究酶的分子结构变化、酶功能、生物性能和其他影响种群遗传学的因素之间的机制联系。这些结果将阐明对栖息地的局部适应与更普遍和更长期的问题之间的关系，这些问题包括物种之间的适应专业化如何不同，不同种类的生物如何以相同或平行的方式适应共同的环境压力。它们还将有助于了解保护遗传学、农业遗传学以及潜在的全球变化对生物的影响，如当地栖息地类型的变化等方面的重要问题。

IBN-0117754, Ward WattSpatial patterns of inherited variation in natural populations can give important clues to the means by which living creatures adapt to their habitats. But patterns alone can result from different causes (e.g., natural selection by local conditions, migration patterns of organisms with different traits, historical artifacts, etc.). This study attempts to elucidate causes of an interesting pattern of variation in which, despite extensive migration among habitats, groups of individuals living in adjacent habitat types are less similar to each other than they are to groups living in a similar habitat types hundreds of kilometers away. This research will focus on in the insect genus, Colias, and will focus on variation in a key enzyme in the energy-processing system that supports the insects' flight in the wild, phosphoglucose isomerase (PGI). Extensive previous work on selection and energetics on Colias in the wild and the insect's distribution patterns in montane areas make it an ideal system for addressing these questions.The investigators will test several alternative plausible explanations for this phenomenon, examining the multiple potential causes of geographical variation in organismal traits. These tests will include studies of the mechanistic links between variation in molecular structure of enzymes, enzyme function, organismal performance, and other factors that influence population genetics. The results will illuminate the relationship between local adaptations to habitat and more general and longer-term questions of how adaptive specialization varies among species and how different kinds of organisms may or may not adapt to common environmental stresses in the same or parallel ways. They will also help inform important issues in the genetics of conservation, the genetics of agriculture, and the biological impacts of potential global change as manifested in changes of local habitat types.