Smithsonian National Zoological Park l Friends of the National Zoo



Becky Cramer

Postdoctoral Fellow / Migratory Bird Center

Research Focus

Birds have an incredible diversity of sexual displays, and my research focuses on understanding such sexual traits. During my PhD at Cornell University, I studied how house wren males use their songs to communicate with other males and with females. Because many house wren females copulate with multiple males, I also investigated whether sperm traits relate to how many chicks a male sires with a given female. During my first postdoc at the University of Oslo, I studied whether divergence in sperm characteristics between bird species causes sperm from one species to perform poorly in females of other species. That is, I investigated whether sperm might represent a reproductive barrier between species. In my current postdoc at the Migratory Bird Center, I’m returning to a within-species perspective and exploring a new methodological approach. Specifically, we’ll be testing whether social network analysis allows us to measure sexual selection more accurately, using a long-term dataset on black-throated blue warblers.