Environmental, Endocrine and Epigenetic Drivers of Sociality in Birds

影响动物形态、生理和行为特征变化的机制很重要，因为它们决定了生物体如何应对环境挑战，因为这些反应会影响生命后期的行为。最近的证据表明，所谓的表观遗传机制可以影响动物对环境变化的反应。表观遗传机制是基因表达的可遗传变化，不编码在DNA序列中。当表观遗传变化发生在生命早期时，可能会对生理和行为产生长期影响。例如，在发育过程中控制应激激素受体的机制中增加的DNA甲基化（表观遗传控制的一种形式）会损害成年人对压力的生理反应。因为应对压力是人类和非人类应对环境变化的一种核心方式，所以确定发育压力源是否以及如何在整个生命过程中对生物体产生负面影响将是很重要的。通过对肯尼亚超椋鸟（Lamprotornis superbus）的长期研究，该项目将(1)探索环境压力源对应激激素受体机制以及整个基因组中DNA甲基化的发育影响，随后(2)通过长期DNA收集、应激激素样本和实验操作确定发育过程中的DNA甲基化如何影响成年应激生理、生殖行为和适应性。这项工作将为在非模式生物中使用表观遗传工具的研究创造新的途径，从中吸取的经验教训可以应用于包括人类在内的其他模式系统。这项研究将通过实地课程、研讨会以及实地和实验室的研究项目对美国和肯尼亚学生进行培训。研究人员还将与肯尼亚的一个基层保护组织密切合作，向农村学校的儿童传授保护濒危生物和生态系统以及气候变化的知识。

The mechanisms that influence variation in the morphological, physiological, and behavioral characteristics of animals are important because they determine how organisms cope with environmental challenges, and because these responses can affect behavior in later stages of life. Recent evidence suggests that so-called epigenetic mechanisms can affect how animals respond to environmental change. Epigenetic mechanisms are heritable changes in gene expression that are not encoded in the DNA sequence. When epigenetic changes occur early in life, there can be long-term consequences for physiology and behavior. For example, increased DNA methylation (a form of epigenetic control) in the machinery that controls the receptor for stress hormone during development can impair an adult's physiological response to stress. Because coping with stress represents a central way in which both humans and non-humans respond to environment change, it will be important to determine if and how developmental stressors might negatively affect organisms throughout their lives. Using a long-term study of superb starlings (Lamprotornis superbus) in Kenya this project will (1) explore the developmental effects of environmental stressors on DNA methylation in the stress hormone receptor machinery, as well as in the entire genome, and subsequently (2) determine how DNA methylation during development affects adult stress physiology, reproductive behavior, and fitness using a long-term DNA collection, stress hormone samples, and experimental manipulations. This work will create new avenues of research using epigenetic tools in non-model organisms, where the lessons learned can be applied back to other model systems including humans. This study will train American and Kenyan students through field courses, workshops, and research projects in the field and lab. Researchers will also work closely with a grassroots conservation organization in Kenya to educate rural school children about conservation and wildlife of threatened organisms and ecosystems and about climate change.