FACULTY SPONSOR: Paul W. Sherman STUDENT: Mark E. Hauber
Most birds and mammals are reared among family members. Therefore, learning the characteristics of siblings and parents results in appropriate species recognition. Because brood parasites lay their eggs in nests of other birds, imprinting on foster parents would lead their young to misidentify their own species. How does recognition develop in parasites? This project investigates species recognition in the brown-headed cowbird (Molothrus ater), a common brood parasitic bird of North America. By combining continuous observations at naturally parasitized nests, selective removals of female parasites to limit early social experience of fledgling cowbirds, DNA parentage analyses, playbacks of conspecific vocalizations throughout parasitic offspring development, and plumage manipulations of hand-reared juveniles, this study evaluates the relative importance of social learning and self-referent phenotype matching in the development of cowbird species recognition. This study will be informative for research on species-, kin-, and mate-recognition mechanisms in general. In addition, because species recognition is a poorly known aspect of the biology of most host-parasite systems, findings from this work will also increase our understanding of host- and self-recognition.
