Dissertation Research: Evolutionary and Ecological Determinants of Incubation Strategies in Three Sympatric Nuthatches

马丁9701116 父母照顾策略的演变被认为是由提供照顾的健身成本和收益决定的。鸟类孵化是一种父母照顾的形式，能量限制被认为是孵化策略中种内和种间变异的基础。然而，这些结论几乎完全是基于单一物种的研究，可能反映表型而不是遗传差异。巢捕食是另一种解释，已被提出作为一个潜在的选择压力，导致不同的孵化策略，但缺乏关键的测试。PI建议实验测试的能量约束和巢捕食风险假说在三个同域物种的属Sitta。这些物种提供了一个模型系统来测试这些假设，因为它们在相反的方向上不同的精力充沛的限制和巢捕食风险。能量约束假说将通过实验来测试修改巢微气候使用温暖和寒冷的空气泵入巢。巢捕食风险假说将通过捕食者演示实验进行测试。这种实验和比较的实地工作的理解负责内部和种间变异的因素在父母的照顾。 L J

Martin 9701116 Evolution of parental care strategies is thought to be determined by fitness costs and benefits associated with providing care. Avian incubation is a form of parental care and energetic constraints are thought to underlie intra- and interspecific variation in incubation strategies. However, these conclusions are based almost exclusively on single species studies which may reflect phenotypic rather than genetic differences. Nest predation is an alternative explanation that has been proposed as a potential selection pressure leading to different incubation strategies, but critical tests are lacking. The PIs propose to experimentally test the energetic constraint and nest predation risk hypotheses in three sympatric species in the genus Sitta. These species provide a model system to test these hypotheses because they differ in opposite directions with respect to energetic constraints and nest predation risk. The energetic constraint hypothesis will be tested by experimentally modifying the nest microclimate using warm and cold air pumped into nests. The nest predation risk hypothesis will be tested through predator presentation experiments. This experimental and comparative field work advances understanding of the factors responsible for intra and interspecific variation in parental care. l J