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B.A., 1985, Cornell University (Biological Sciences) Ph.D., 1991, University of California at Berkeley (Zoology)
email: usavalli@earthlink.net |
Currently I am working with two species of seed beetles (Family Bruchidae), the cowpea weavil, Callosobruchus maculatus, and a desert seed beetle, Stator limbatus. I am investigating the roles of male-male competition, sperm competition and female choice in the evolution of male body size, ejaculate size and sexual dimorphism (males are larger than females in S. limbatus while the reverse is true for C. maculatus) and female reproductive strategies such as mate choice, multiple mating, and egg size decisions.
My dissertation research was a field project--at the Kakamega
National Reserve, Western Kenya--studying sexual selection in yellow-shouldered widowbirds, Euplectes macrourus . I investigated the evolution of the long tails of males. Using experimental manipulations of tail length, I demonstrated that tail length functions primarily in male-male competition for territories. On the other hand, I found no evidence for female choice of long-tailed males; instead, females seem to select males on the basis of territory attributes, particularly the number of "cock's nests" a male builds. In addition to examining the role of sexual selection, I also considered non-sexual selection alternatives (e.g. species recognition, aposematism/unprofitable prey, and genetic drift) to the evolution of long tails, using both field data and a comparative approach.
For a more detailed description of the widowbird research, click here.
Birdnet the master site for all of the North American Ornithological Societies, with many links.
Ornithology Web Site includes photos and links to a few research projects
Birding on the Web many links to bird related sites (not just bird watching)
Animal Behavior Society
Nebraska Behavioral Biology Group information about their own program plus links to many other relevant sites
Animal Behavior at Indiana University
Evolution Links
The Tree of Life
For additional links to more specific research sites, visit the widowbird or beetle pages
This page last modified on January 6, 2002, by Udo M.
Savalli (usavalli@earthlink.net)