Montane Biogeography Revealed by Quirks of the Evolutionary Process: Integrative Respiratory Phenotypes for Andean Birds

高海拔地区的动物利用各种机制来获取足够的氧气，尽管大气压力很低。单个动物可以实时改变它们的呼吸策略，就像人类在高海拔训练中增加红细胞的浓度和大小一样。另外，高海拔地区的人口可以通过世代的自然选择在基因上适应，有效地优化呼吸系统以适应低环境氧压。这个项目将描述几十种野生鸟类的高海拔呼吸策略。研究类群由不同进化分化水平的高海拔种群和低海拔种群对组成。国际团队将沿着安第斯山脉的海拔梯度对鸟类进行采样，以评估关键呼吸系统成分的结构和性能，包括心脏、肺、血液、血红蛋白和缺氧诱导的基因表达级联。有了这些数据，本项目将(1)建立一个高海拔适应的时间过程模型，(2)描述这种常见生理挑战的解决方案的多样性。这种新的模型和比较数据将有助于通过整合生理和系统发育信息来推断生物地理历史。研究结果将揭示呼吸特化对安第斯鸟类的独特性和多样性的贡献。美国和秘鲁学生将在该项目的研究考察期间建立国际伙伴关系。标本和相关数据将在博物馆收藏和在线数据库中存档。安第斯鸟类谱系与高海拔地区的人类种群相似，由于缺氧在人类病理中的深刻作用，它们的缺氧防御机制受到广泛关注。

Animals at high altitudes use a variety of mechanisms to acquire sufficient oxygen despite low atmospheric pressure. Individual animals can shift their respiratory strategies in real time, just as humans increase the concentration and size of red blood cells during high-altitude training. Alternatively, high-altitude populations can genetically adapt by natural selection over generations, effectively optimizing their respiratory systems for low ambient oxygen pressure. This project will characterize the high-altitude respiratory strategies of dozens of wild bird species. Study taxa comprise pairs of related high-altitude and low-altitude populations at different levels of evolutionary divergence. International teams will sample birds along elevational gradients in the Andes to evaluate the structure and performance of critical respiratory system components, including heart, lungs, blood, hemoglobin, and the hypoxia-induced gene-expression cascade. With these data, this project will (1) develop a model of the time-course of high-altitude adaptation and (2) describe the diversity of solutions to this common physiological challenge. This new model and comparative data will facilitate inference of biogeographic history through integration of physiological and phylogenetic information. The results will reveal the contribution of respiratory specialization to the uniqueness and diversity of the Andean avifauna.American and Peruvian students will develop international partnerships during the project's research expeditions. Specimens and linked data will be archived in museum collections and online databases. Andean bird lineages provide analogues to high-altitude human populations and their hypoxia defense mechanisms are of broad interest due to the profound role of hypoxia in human pathology.