Using DNA sequences to study population history is growing in popularity, but many methods assume the DNA studied is not influenced by natural selection. Thus, scientists often focus on DNA that does not code for proteins and is assumed to be free from selection. However, this assumption may be faulty. This project will examine the influence of selection on non-coding DNA and will evaluate the sensitivity of various methods to this problem. Sequences from twenty independent regions of DNA sampled from six co-distributed species of Holarctic ducks will be compared to data simulated without selection.
Results from this study will be broadly applicable, as non-coding DNA is often used for setting conservation and management priorities, studying species' responses to climate change, and understanding ecology and natural history. Also, the six species have a circumpolar distribution, and our project includes many birds from Arctic Alaska and Russia. Results will provide baseline data for examining responses to changing environments; for example, climate change may be contributing to the decline of one species and the expansion of two. Finally, this project will provide opportunities for postdoctoral training, undergraduate research, secondary education outreach, and expansion of a long-term collaboration between US and Russian scientists.