Nicole M. Gerlach, Ph.D.
E-mail: nmgerlac AT indiana DOT edu
Why do some but not all females engage in extra-pair behavior?
My research involves extra-pair behavior in female dark-eyed juncos (Junco hyemalis). Extra-pair behavior in songbirds has been well-studied from the perspective of male behavior, but much less so from the female perspective. About a quarter of all junco offspring are produced by extra-pair mating, although individual females vary from highly faithful (no EPO) to highly unfaithful (all EPO). My research is aimed at understanding the sources of this individual variation from both ultimate and proximate perspectives, as well as the effects that extra-pair behavior has on fitness.
To this end, I have genotyped samples from almost 2400 nestlings and adults from 1997-2011, and used these genotypes to determine the paternity of more than one thousand nestlings. I have also compiled a long-term database based on almost 30 years of research on free-living juncos from Mountain Lake Biological Station in Giles County in southwest Virginia. The database contains information on the demography, morphology, and reproduction of over 15,000 individual birds, including more than 2,000 nestlings whose genetic paternity is known.