Collaborative Research: Energetic consequences of rain and nest structure for ecology and evolution of songbirds in tropical rainforests

合作研究：降雨和巢结构对热带雨林鸣禽生态和进化的能量影响

• 批准号: 1656273
• 负责人: Blair Wolf
• 金额: $ 30.04万
• 依托单位: University of New Mexico
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-15 至 2021-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1656273&HistoricalAwards=false
• 关键词: Collaborative; Research; Energetic; consequences; rain

Rainfall varies extensively among biomes and over time with weather cycles like El Niño. Lab studies have shown that warm-blooded organisms lose heat at a more rapid rate when wet and must spend more energy to regulate body temperature. Effects of rainfall on energy expenditure in the wild is unstudied, but may critically affect reproduction and survival of organisms. Energy is often most limited to animals when trying to raise offspring, with the latter especially vulnerable to increased energy costs of wetting because of poorly developed fur or feathers. This project examines energy costs of rainfall to parents and their offspring in tropical songbirds. Tropical organisms provide an important test because they are thought to be sensitive to heat loss and thermal conditions due to the narrow temperature variation in the tropics. Also, rain is a prevalent feature in tropical rain forests (often 2 m per year). Investigations will examine energy expenditure of both parents and offspring on dry versus wet days and at nests where rainfall is experimentally modified. Measurements will be conducted across diverse species that differ in their behaviors, nest types and potential exposure to rain to advance understanding of the energetic costs and differential population vulnerabilities of species as a result of variation in rainfall. This work has important conservation implications because it identifies population sensitivities of endemic species in a biodiversity hotspot. In addition, many students from a variety of disciplines, including those outside of biology will be trained in the conduct of field work and scientific principles. Ecological and evolutionary influences of precipitation are poorly studied. Proposed work will significantly advance understanding of the energetic (field metabolic rates) and demographic consequences of variation in rainfall on coexisting songbirds in a tropical rainforest. These costs may be strongly expressed in tropical rainforests where rain is prevalent, thermal tolerances are narrow, and temperatures are often below thermoneutral levels. Yet, studies of the effects of rainfall and wetting on energetics, behavior and demography across diverse tropical species are lacking. The proposed work will use novel experimental and observational approaches to advance understanding of how nest structure affects energy use of parents due to heat loss under wet versus dry conditions. The proposed work will also elucidate how rain, temperature, nest structure, and parental behavior combine to affect energy expenditure of offspring and how energy is allocated to differing body components during growth. Finally, it will reveal demographic ramifications of the physiological costs of rain and nest structure to gain new insight into fitness consequences. Ultimately, this work will provide a new understanding of the influences of climate and nest structure upon heat balance and evolution of parental and growth strategies among diverse species. This work will also identify relative demographic sensitivities of species as a function of their nest types, ecologies and behaviors to aid prioritization schemes for conservation. A large number of undergraduate and graduate students, as well as a post-doctoral scholar, will receive training in diverse field methodologies and scientific principles.

降雨量在生物群落之间变化很大，并随着时间的推移而变化，如厄尔尼诺现象。实验室研究表明，温血生物在潮湿时以更快的速度失去热量，必须花费更多的能量来调节体温。降雨对野外能量消耗的影响尚未研究，但可能严重影响生物体的繁殖和生存。当动物试图养育后代时，能量通常最有限，后者特别容易受到由于毛发或羽毛发育不良而增加的润湿能量成本的影响。这个项目研究了热带鸣禽父母和他们的后代在降雨中的能量消耗。热带生物提供了一个重要的测试，因为它们被认为是敏感的热损失和热条件，由于在热带地区的温度变化很小。此外，降雨是热带雨林的普遍特征（通常每年2米）。 调查将检查能量消耗的父母和后代在干燥与潮湿的日子，并在巢降雨实验修改。测量将在不同的物种，不同的行为，巢类型和潜在的暴露于雨，以促进能源成本和物种的差异人口脆弱性的理解，由于降雨量的变化。这项工作具有重要的保护意义，因为它确定了生物多样性热点地区特有物种的种群敏感性。此外，许多来自不同学科的学生，包括生物学以外的学生，将接受实地工作和科学原则的培训。降水对生态和进化的影响研究甚少。拟议的工作将显着推进的精力充沛的理解（现场代谢率）和人口的变化，降雨对共存的鸣禽在热带雨林中的后果。这些成本可能在热带雨林中表现得很明显，那里雨水充沛，耐热性很窄，温度通常低于热中性水平。然而，降雨和湿润对不同热带物种的能量，行为和人口统计学的影响的研究还很缺乏。拟议的工作将使用新的实验和观察方法，以促进了解巢结构如何影响父母的能量使用，由于在潮湿与干燥条件下的热量损失。拟议的工作还将阐明如何雨水，温度，巢结构，和父母的行为联合收割机结合起来，影响后代的能量消耗和如何在生长过程中的能量分配给不同的身体组成部分。最后，它将揭示人口的生理成本的雨水和巢结构，以获得新的洞察健身的后果。最终，这项工作将提供一个新的理解气候和巢结构的影响后，热平衡和不同物种之间的父母和生长策略的演变。这项工作还将确定物种的相对人口敏感性，作为其巢穴类型，生态和行为的函数，以帮助优先保护计划。大量的本科生和研究生，以及博士后学者，将接受不同领域的方法和科学原理的培训。