DISSERTATION RESEARCH: PHENOTYPIC RESPONSES TO URBAN HABITATS: A POTENTIAL ROLE FOR DNA METHYLATION

城市地区正在迅速扩大，这给野生动物带来了机遇和挑战。虽然一些物种在城市地区表现不佳，但其他物种却表现良好。以前的研究已经记录了同一物种的城市和农村个体之间的许多差异，但对这些差异是如何产生和维持的知之甚少。一种可能的机制是DNA甲基化，这是一种在不改变潜在遗传密码的情况下影响基因表达的过程。DNA甲基化模式可以遗传，但也可能在个体一生中因环境刺激而改变。由于DNA甲基化能够使生物体的外部特征发生快速、稳定和可遗传的变化，因此它是解释物种如何适应新的栖息地和环境（包括城市化）的主要候选者。这项研究将比较城市和农村鸣禽的DNA甲基化模式，并将这些模式与之前观察到的差异联系起来，特别是这些相同群体之间的攻击性行为和应激激素水平。预测了城市和农村鸟类在DNA甲基化水平和位置上的差异，以及甲基化模式与观察到的行为和生理差异之间的关系。这项研究的结果将具有广泛的适用性，因为DNA甲基化是一个在从真菌到植物到动物，包括人类的分类群中发现的过程。这项研究将增加对城市栖息地如何影响生活在其中的当代和后代生物的理解，随着城市地区的不断发展，这一知识尤为重要。最后，两名本科生将参与这项研究，给他们宝贵的研究经验，将推动他们走向科学事业。此外，将为当地自然中心创建探索城市化对动物和人类影响的活动，让更广泛的公众意识到这项研究的重要性。

Urban areas are rapidly expanding and present both opportunities and challenges for wild animals. While some species do poorly in urban areas, others do well. Previous research has documented many differences between urban and rural individuals of the same species, but little is known about how these differences are created and maintained. One possible mechanism is DNA methylation, a process that affects gene expression without changing the underlying genetic code. Patterns of DNA methylation can be inherited, but may also change within an individual's lifetime in response to environmental stimuli. Because DNA methylation enables rapid yet stable and heritable changes of an organism's outward characteristics, it is a prime candidate for explaining how species adapt to novel habitats and situations, including urbanization. This study will compare DNA methylation patterns of urban and rural songbirds and relate these patterns to previously observed differences, specifically aggressive behavior and stress hormone levels, between these same groups. Differences between urban and rural birds in DNA methylation levels and locations are predicted, as is a relationship between methylation patterns and observed differences in behavior and physiology. The results of this research will be broadly applicable, as DNA methylation is a process found in taxa ranging from fungi to plants to animals, including humans. This study will increase understanding of how urban habitats can affect current and future generations of organisms living in them, knowledge that is especially important as urban areas continue to grow. Finally, two undergraduate students will participate in this study, giving them valuable research experience that will advance them towards a career in science. In addition, activities exploring the impacts of urbanization on animals and humans will be created for the local nature center giving the broader public an awareness of why this research is important.