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.
