Natural selection is a potentially powerful force of evolutionary change and yet, how an animal's traits influence its action is poorly understood. This is surprising, as being armed with this knowledge will allow researchers to better understand many aspects of basic population biology. This study, on the relationship between sexual behavior and natural selection (a mechanism of adaptive evolution) on genes of the Major Histocompatibility Complex (the genes underlying vertebrate immune function), will relate vastly different sexual behaviors (monogamy versus promiscuity) to striking differences in genes. This study tests the hypothesis that the increased rate of infection by parasites and pathogens in promiscuous species leads to adaptive evolution at genes that control immune function. One specific class of pathogen hypothesized to be underlying this relationship is harmful bacteria transferred during mating. This study uses wild animals (deer mice) and genetic techniques such as PCR (targeted amplification of DNA), cloning (a technique to separate different DNA sequences), and DNA sequencing to identify differences. Vaginal bacteria will be collected using a swabbing technique. Individual bacterial species will be identified using molecular techniques. Undergraduate training opportunities will be available for both lab and field components of the project. The fundamental relationships between animal behavior, pathogen transfer, and adaptive evolution of genes of the immune system is poorly understood, yet is critical to understanding many aspects of population biology. This study will allow for a better understanding of these relationships, and in the process, integrate several distinct scientific disciplines and provide opportunity for undergraduate training.
