Behavior and Ethology Commons^™

The Major Histocompatibility Complex In Song Sparrows: Immunity, Signals, And Mate Choice, Joel W.G. Slade

Electronic Thesis and Dissertation Repository

In recent years, sexual selection theory has redefined genetic quality to consider not only additive genetic effects on fitness but also non-additive genetic effects, such as heterozygote advantage or disadvantage. In jawed vertebrates, the major histocompatibility complex (MHC) gene family has been shown to exhibit both additive and non-additive genetic effects on fitness. MHC gene products are involved in initiating adaptive immune responses, and MHC genotype determines the range of pathogens to which an individual can respond. Therefore, parasite-mediated selection at MHC may favour locally-adapted, rare, or particular combination of alleles. Because heterozygote advantage at MHC is widespread, sexual selection …