Ecology and evolutionary biology of stress in birds

我的总体目标是从生活史的角度研究鸟类应激的原因和后果。压力在动物的生活中无处不在，对它们的健康有无处不在的后果。个体如何感知、应对和应对应激源，对动物的生理、行为和生态至关重要。生理机制如何调节动物与其环境之间的关系，有助于我们更好地理解生活史的多样性，即优化有限资源配置的策略。当动物暴露在应激源下时，生活史的权衡尤其值得注意，因为它们必须在处理应激源和维持状况的相互竞争的需求之间分配有限的资源(如能量、类胡萝卜素等营养物质、免疫功能)。可检验的假设是，最优策略应该随着个体状况和压力源的性质的成本而变化。我使用野生鸟类和圈养鸟类来研究在繁殖努力、性装饰以及鸟类如何应对人为干扰方面的压力。虽然我会用很多方法来评估条件、健康和压力，但我会特别使用我开发的一种新技术来量化羽毛中的皮质酮(应激激素)，这种技术允许对应激生理学进行长期评估(几天到几个月)。我将操纵寄生虫载量、饮食、食物供应和环境温度等应激源，以调查压力在调节父母努力与条件、数量与后代质量等权衡中的作用。同样，我将通过实验研究皮质酮和睾酮如何在使用类胡萝卜素着色性装饰品和免疫功能之间进行权衡。我还通过植入物直接控制荷尔蒙水平，并从药理学上测试下丘脑-垂体-肾上腺(压力)轴组件的能力，这可能有助于解释物种内部和物种之间对压力的反应和后果的巨大差异。我的方法的新颖性将把压力研究领域带入新的方向，对基础科学、兽医学、畜牧业、保护生物学和野生动物管理产生影响。

My general objective is to study causes and consequences of stress in birds from a life history perspective. Stress is ubiquitous in the lives of animals with pervasive consequences to their well being. How individuals perceive, respond to and cope with stressors is crucial to an animal's physiology, behaviour and ecology. How physiological mechanisms mediate the relationship between the animal and its environment help us better understand the diversification of life histories, i.e., strategies to optimize the allocation of limited resources. Life history trade offs are particularly notable when animals are exposed to stressors for they must allocate limited resources (e.g. energy, nutrients such as carotenoids, immune function) between the competing demands of dealing with the stressor and maintaining condition. The testable hypothesis is that the optimal strategy should vary with the cost to individual condition and nature of the stressor. I use both wild and captive birds to study stress in the context of reproductive effort, sexual ornamentation and how birds deal with anthropogenic disturbances. Although I will assess condition, health and stress in many ways, I will especially use a novel technique I developed for quantifying corticosterone (stress hormone) in feathers that allows for a long-term evaluation (days to months) of stress physiology. I will manipulate such stressors as parasite loads, diet, food supply and environmental temperature to investigate the role of stress in mediating such trade offs as parental effort vs condition, and number vs quality of offspring. Similarly, I will investigate experimentally how corticosterone and testosterone mediate trade offs between the use of carotenoids for coloration of sexual ornaments vs. immune function. I also directly manipulate hormone levels with implants, and pharmacologically test the capacity of components of the hypothalamic-pituitary-adrenal (stress) axis that may help explain the great variation within and among species in their response to, and consequences of, stress. The novelty of my approach will take the field of stress research in new directions, with impacts in basic science, veterinary medicine, animal husbandry, conservation biology and wildlife management.