Collaborative Research: Costs and Trade-offs of Phenotypically Flexible Responses to Winter Temperature Variability in Birds

全球气候变化正在导致冬季变暖，但也使冬季气温更加多变。这种变化包括更频繁的寒流。温度波动的增加可能会给鸟类和其他动物带来挑战。鸟类可以调整自己的生理机能来应对温度的波动。然而，目前还不确定鸟类是否能足够快地做出反应，以适应这些波动。这种不确定性使得冬季鸟类的保护计划变得困难。这个项目将研究鸟类如何应对冬季气温的波动。这项研究还将确定调整生理机能的成本，这可能会限制鸟类对温度波动的反应。自然研究和实验室研究都将用于回答鸟类如何能够适应温度波动的问题。这些研究还将确定哪些水平（组织、细胞、亚细胞）参与了这些调整。该项目将为鸟类应对未来气候变化下预期的温度波动的能力提供一个广泛的视角。该项目将涉及处于职业生涯不同阶段的早期和成熟的教师和学生。这些研究还将吸引土著和非裔美国大学生。该项目的另一个目标是让各种各样的人参与进来，帮助提高科学素养。该项目的目标是为中小学生和普通大众开展活动。该项目的数据还将有助于开发模型方法来预测鸟类对气候变化的反应，从而更好地评估保护影响。美国中北部的冬季平均气温正在迅速上升，但与此趋势相叠加的是更多的温度变化，包括更频繁的寒流。这种间断的寒冷期需要鸟类灵活地调整体温调节生理以适应环境条件，并可能导致生理-环境不匹配。灵活的生理反应使鸟类能够更好地将代谢表型与变化的气候相匹配，并能产生健康益处。然而，人们对这种灵活性的代价知之甚少，这是未来研究的建议目标，也是了解生物对气候变化模型预测的日益增加的气候变化作出反应的能力的关键因素。该项目研究了鸟类在有机体、细胞和分子水平上对温度波动的反应，包括研究对自然季节和季节内温度变化的反应，以及对温暖、寒冷和寒冷波动温度的实验温度适应研究。这些综合研究将为未来气候变化情景下鸟类对温度变化的灵活代谢反应的机制、成本、权衡和适应性后果提供前所未有的视角。该合作项目将涉及高级和初级教师、博士后、研究生和本科生。该项目还将吸引土著和非裔美国本科生，并将让K-12学生和普通公众参与与项目目标有关的科学活动，以帮助提高科学素养。该项目的数据还有望通过促进将生理灵活性和温度变化纳入下一代鸟类对气候变化的反应模型中，从而使其受益。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。

Global climate change is producing winter warming but also more variable winter temperatures. This variability includes more frequent cold snaps. This increase in temperature fluctuation may create challenges for birds and other animals. Birds can adjust their physiology to respond to fluctuating temperatures. It is uncertain, however, if birds can respond fast enough to match these fluctuations. This uncertainty makes conservation planning for winter birds difficult. This project will study how birds respond to fluctuations in winter temperatures. The study will also identify costs of adjusting physiology that might limit how well birds can respond to fluctuating temperatures. Both natural and laboratory studies will be used to answer questions about how birds are able to adjust to temperature fluctuations. These studies will also determine what levels (tissues, cells, sub-cellular) are involved in these adjustments. The project will provide a broad view of the ability of birds to respond to temperature fluctuations expected under future climate change. The project will involve early-career and established faculty and students at various stages in their careers. The studies will also engage Indigenous and African-American college students. Another goal of the project is to involve a diversity of people to help improve scientific literacy. The project targets activities for elementary and high school students and the general public for this purpose. Data from the project are also expected to assist development of modeling approaches to predict bird responses to climate change to better assess conservation impacts. Mean winter temperatures are increasing rapidly in the north-central U.S. but superimposed on this trend is more temperature variability, including more frequent cold snaps. Such punctuated cold periods will require flexible adjustments of thermoregulatory physiology of birds to match environmental conditions and could lead to physiology-environment mismatches. Flexible physiological responses allow birds to better match metabolic phenotypes to variable climates and can produce fitness benefits. The costs of such flexibility, however, are poorly known, are recommended targets of future research, and are critical elements to understand the capacities of organisms to respond to increasing climatic variability projected by climate change models. This project examines avian metabolic flexibility in response to fluctuating temperatures at organismal, cellular and molecular levels, including studies examining responses to natural seasonal and within-season temperature variation and experimental temperature acclimation studies with warm, cold, and fluctuating cold temperatures. These integrative studies will provide an unprecedented view of the mechanisms, costs, trade-offs, and fitness consequences of flexible metabolic responses of birds to increasing temperature variability expected under future climate change scenarios. The collaborative project will involve senior and junior-level faculty, a postdoctoral fellow, graduate and undergraduate students. The project will also engage Indigenous and African-American undergraduate students and will involve K-12 students and the general public in scientific activities related to project goals to help improve scientific literacy. Data from the project are also expected to benefit next-generation models of bird responses to climate change by facilitating incorporation of physiological flexibility and temperature variability into such models.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.