Dissertation Research: Climate Change, Range Limits and Adaptive Potential: Latitudinal variation in thermal tolerance in the copepod Tigriopus californicus?

快速的气候变化威胁着许多物种的灭绝。如果一个物种能够1)改变其地理分布以适应不断变化的环境，或者2)进化出更强的适应新环境的能力，它就可以避免灭绝。一个物种适应不断变化的环境的能力将取决于基因变异的数量，比如对极端温度的耐受性。然而，人们对这些性状在自然界中存在多少变异知之甚少。pi将使用虾状的潮汐动物加利福尼亚虎爪作为代表性研究生物来解决这些问题。这种微小的海洋甲壳类动物生活在北美太平洋沿岸的上游潮汐池中。pi正在从横跨900英里的8个地点收集Tigriopus，以建立30个实验室种群。他们的实验将把这些种群暴露在不断升高的温度下，持续数代，以追踪种群对环境变化的反应过程。这些实验将测量温度耐受性的遗传变异，并将测试对变暖温度的进化反应能力。学生PI在指导本科生方面非常成功，并将继续让他们参与研究。这个项目将增加对进化在物种面对气候变化时避免灭绝的能力中所起作用的理解。通过描述一个重要特征的地理变异，这个项目的结果也将为管理者提供一个有价值的决策工具，当优先考虑栖息地和种群保护时。

The rapid pace of climate change threatens many species with extinction. A species may avoid extinction if it is able to either 1) shift its geographic distribution to track the changing environment, or 2) evolve greater tolerance of new conditions. The ability of a species to adapt to a changing environment will depend on the amount of genetic variation for traits like tolerance of extreme temperatures. However, very little is known about how much variation exists for these kinds of traits in nature. The PIs will address these issues using the shrimp-like tidepool animal, Tigriopus californicus, as a representative study organism. This tiny marine crustacean lives in upper shore tidepools along the Pacific coast of North America. The PIs are collecting Tigriopus from eight sites spanning over 900 miles to establish 30 laboratory populations. Their experiments will expose these populations to increasing temperatures for multiple generations, to track the course of population changes in response to environmental change. These experiments will measure genetic variation for temperature tolerance and will test the capacity for an evolutionary response to warming temperatures. The student PI has been very successful in mentoring undergraduates and will continue to involve them in the research. This project will add to the understanding of the role of evolution in contributing to a species' ability to avoid extinction in the face of climate change. By describing geographic variation in an important trait, the results of this project will also provide managers with a valuable decision-making tool when prioritizing habitats and populations for conservation.