DISSERTATION RESEARCH: Temperature-Dependent Phylogeography and Limits of Thermal Tolerance in Anolis carolinensis

该项目旨在了解限制陆生外温（“冷血”）动物（如爬行动物，两栖动物和昆虫）耐热性的生理压力，以及这些限制如何影响物种在气候变化中生存的能力。极端温度阻止所有的外温物种有效地利用氧气的假设已被广泛应用于解释热耐受性的限制。然而，这一假设已经在水生物种中得到了大量的验证，这就提出了一个问题：同样的生理压力会影响呼吸空气的物种吗？利用绿色变色蜥蜴（Anolis carolinensis），研究人员试图通过将生理实验与基因组测序相结合来直接比较极端温度下的基因反应与已知的缺氧遗传反应来回答这个问题。通过这种方法，研究人员试图阐明陆生外温动物生存、发挥功能和适应新的热生态位的生理机制和进化过程。为了充分了解气候变化如何影响生物多样性，必须将环境变化信息与物种缓冲、适应、并通过生理和遗传机制适应这种变化。该项目旨在通过将物种范围内的热差异信息与蜥蜴热生物学和基因组资源的丰富知识相结合来实现这一目标。结合这些工具将有助于更好地预测气候变化将如何影响世界各地物种的分布范围和丰度。这项研究还将导致一个研究生的培训，并将提供研究经验的几个本科生。

This project aims to understand the physiological stresses that limit thermal tolerance in terrestrial ectothermic ("cold-blooded") animals (such as reptiles, amphibians and insects) and how those limitations affect a species' ability to survive changes climate. The hypothesis that extreme temperatures prevent all ectothermic species from effectively using oxygen has been widely applied to explain the limits of thermal tolerance. However, this hypothesis has been most heavily tested in aquatic species, raising the question: Does the same physiological stress effect air breathing species? Using the green anole lizard (Anolis carolinensis), the investigators seek to answer this question by combining physiological experimentation with genome sequencing to directly compare gene response under extreme temperatures to known genetic responses to hypoxia. Through this approach, the investigators seek to shed valuable light on the physiological mechanisms and evolutionary processes that allow terrestrial ectotherms to survive, function, and adapt to novel thermal niches.In order to fully understand how climate change will affect biodiversity it is essential to integrate information about environmental change with data about species' ability to buffer, acclimate, and adapt to that change via physiological and genetic mechanisms. This project serves to accomplish this by combining information about thermal differences within the range of a species with the wealth of knowledge on the thermal biology of lizards and genomic resources only made available within the last few years. Combining these tools will allow for better predictions of how changes in climate will affect species' ranges and abundances around the world. This research will also result in the training of a graduate student and will provide research experiences for several undergraduates.