CAREER: Physiological and Behavioral Determinants of Energy Use in Tropical Mammals

利用消耗大量能量的生理过程将体温维持在高于环境温度或恒温的水平，是哺乳动物的一个显著特征。恒温动物的进化使哺乳动物能够从温暖的季节性气候中多样化，并随着温度的下降而辐射到以前不适宜居住的环境中。然而，关于哺乳动物的温度调节和能量学的大部分已知知识都来自高纬度的北半球物种，这些物种的进化史受到温度和极端季节性的巨大变化的影响。为了弥补这一差距，PI将利用现有的合作，研究马来西亚婆罗洲热带森林中夜间和日间小型哺乳动物的生活成本。PI和她的团队将收集自由生活的小型哺乳动物的体温、代谢率和生活史特征的长期数据。一个新的，全面的哺乳动物生理和生活史特征数据库将产生，提供新的，真实的数据，作为气候对哺乳动物能量学影响的宝贵学习经验。教育活动将针对缅因大学的本科生和研究生，以及缅因州各地的K-12学生。通过对来自独特环境的新数据集的第一手体验，学生将学习温度调节生理学在理解动物如何对其环境做出反应方面的重要性。通过增加我们对热带哺乳动物功能能量学的了解，我们不仅可以了解当前物种分布的机制，而且还有助于提高我们对全球气候变化的生物反应的预测。这个早期职业项目的最终目标是建立一个框架，通过整合生理学、生态学和进化生物学，更好地了解哺乳动物的宏观生理学，更好地预测它们对全球变暖的潜在反应。高度的生物多样性、地方性以及印度-马来亚动物地理区域小型哺乳动物基本生理数据的几乎完全缺乏，为开展综合研究和教育的长期项目创造了理想的场所。PI和她的团队试图回答以下问题：1)夜间活动的小型哺乳动物是否比白天活动的同类动物有更灵活的体温；2)在持续炎热潮湿的环境中，夜间活动或白天活动会消耗更多的能源和水吗？ 3)这些差异将如何影响它们应对气候变化的能力。通过回答这些问题，这项研究将产生关于六种或更多热带小型哺乳动物生理和能量学的新数据集。当这些数据与温带哺乳动物的现有数据相结合时，这些数据将用于测试关于恒温进化的假设，以及能量学在哺乳动物生活史中的作用。最终，该研究将产生一个综合框架，利用哺乳动物热调节表型来模拟哺乳动物对气候的反应。该提案的研究目标将与教育活动相结合，该活动将针对缅因大学的本科生和研究生以及整个州的K-12学生。通过对来自独特环境的新数据集的第一手经验，将学习证明体温调节生理学在理解动物如何对其环境做出反应方面的重要性，同时为初级科学家和公众提供研究和推广机会。总之，热带哺乳动物的功能能量学知识将促进对控制当前物种分布机制的理解，但也有助于改善我们对全球气候变化的生物反应的预测。该职业建议得到了生物科学理事会综合有机体系统部综合生态生理学项目和综合活动办公室促进竞争性研究的既定项目（EPSCoR）项目的支持。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The ability to use energetically costly physiological processes to maintain body temperature at levels elevated above ambient temperature or endothermy, is a defining characteristic of mammals. The evolution of endothermy allowed mammals from warm, aseasonal climates to diversify and radiate into previously inhospitable environments as temperatures cooled. Much of what is known about temperature regulation and energetics in mammals, however, has been derived from high latitude, northern hemisphere species whose evolutionary history has been shaped by large changes in temperature and extreme seasonality. To address this gap, the PI will leverage an existing collaboration, to examine the costs of living for nocturnal and diurnal small mammals in the tropical forests of Malaysian Borneo. The PI and her team will collect long term data on the body temperatures, metabolic rates, and life history characteristics of free-living small mammals. A novel, comprehensive database of mammalian physiological and life history traits, will be generated providing access to new, real data as a valuable learning experiences for the impact of climate on mammalian energetics. Education activities will target University of Maine undergraduate and graduate students, and K-12 students throughout Maine. Through first-hand experience with novel datasets from a unique environment, students will learn the importance of thermoregulatory physiology in understanding how animals respond to their environment. By increasing our knowledge of the functional energetics of tropical mammals not only can we understand the mechanisms underpinning current species distributions, but also help to improve our predictions of organismal responses to changing global climates. The ultimate goal of this early career project is to build a framework to better understand the macrophysiology of mammals and better predict their potential responses to a warming world, by integrating physiology, ecology, and evolutionary biology. A high degree of biodiversity, endemism, and an almost complete lack of basic data physiological data available for small mammals from the Indo-Malayan zoogeographic region, creates an ideal arena in which to stage a long-term project of integrated research and education. The PI and her team seek to answer the following questions: 1) do nocturnal small mammals have more flexible body temperatures than their diurnal counterparts; 2) does it cost more (in terms of energy and water) to be nocturnal or diurnal in a consistently hot and humid environment and, 3) how will these differences affect their ability to respond to climate change. Through answering these questions, the research will generate novel datasets on the physiology and energetics of six or more species of tropical small mammals. When combined with existing data from temperate mammals, these data will be used test hypotheses on the evolution of homeothermy, and the role of energetics in the life history of mammals. Ultimately, the research will generate a comprehensive framework for using mammalian thermoregulatory phenotypes in modeling mammalian responses to climate. The research aims of this proposal will be integrated with education activities that will target undergraduate and graduate students at the University of Maine and K-12 students throughout the state. Through first-hand experience with novel datasets from a unique environments, will learn demonstrate the importance of thermoregulatory physiology in understanding how animals respond to their environment, while providing research and outreach opportunities for junior scientists and the general public. Together the knowledge of the functional energetics of tropical mammals will advance the understanding of mechanisms controlling current species distributions, but also help to improve our predictions of organismal responses to changing global climates.This CAREER proposal was supported by the Integrative Ecological Physiology Program within the Division of Integrative Organismal Systems within the Directorate for Biological Sciences and the Established Program to Stimulate Competitive Research (EPSCoR) Program within the Office of Integrative Activities.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.