Graduate Student
Virginia Tech
Contact Information:
4098 Derring Hall
Mail: Dept. of Biological Sciences (0406)
Virginia Polytechnic Institute and State University
Blacksburg, VA 24061
Email: jcastner@vt.edu
Current Research: I am a graduate student in Dr. Ignacio Moore's lab examining the role of cultural divergence in population divergence in two allopatric populations of Rufous-Collared Sparrows (Zonotrichia capensis) in Ecuador.
A current hypothesis regarding tropical bird speciation states that when populations divide geographically, they assume asynchronous breeding cycles due to local abiotic factors, experience song drift, and subsequently rapid genetic divergence occurs. Among some allopatric bird populations, songs drift into different dialects, which upon secondary contact may serve as the primary isolating mechanism due to a lack of recognition as a conspecific. Further, non-local song dialects may fail to stimulate female reproductive physiology resulting in assortative mating. Therefore, differential response to song dialect may represent a behavioral mechanism whereby a culturally transmitted trait (song is learned) affects the genetic structure of populations. I am examining two behavioral factors that could lead to reproductive isolation by examining A) female preference of local dialects and B) stimulatory effects of non-local dialects on female reproductive condition.
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| Rufous-Collared Sparrow (Zonotrichia capensis) | Field site in Papallacta, Ecuador | Playback trials |
| Hawaii | Central America | Alaska |
Hawaii: Palia Restoration Project. A conservation project for the endangered Palila (Loxioides bailleui) bird.
| Julie with Palila | Mauna Kea's shadow | Ray and Julie banding |
Central America: examined agroecosystems and the affect on avian communities by comparing the fitness of Thryothorus wrens in Nicaragua.
| Thryothorus maculipectus | Tree fall gap | Santos, Ulda, Yasser (host family) |
Juneau, Alaska: performed all aspects of mist-netting, parasite sampling, nest searching, behavioral observations, and stream occupancy of American Dippers (Cinclus mexicanus).
Juvenile American Dipper (Cinclus mexicanus) |
Ray nest searching | Julie in Juneau forest |
Links:
"Viva la evolucion!"
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