This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.
This award will support a twenty-four month research fellowship by Dr. Megan Wyman to work with Drs. Karen McComb and David Reby at the University of Sussex in the UK.
Hybridization with introduced species is an important but often overlooked threat to native species survival. Reproductive isolating mechanisms are integral to the process of speciation. These mechanisms often include species-specific signals in the context of mate attraction (to locate and identify appropriate mates) and mate competition (to identify and defend against potential mating competitors). When these isolating mechanisms are weak, hybridization may occur. Vocal communication in the context of sexual selection (mate choice/competition) is used extensively by many deer species and theoretically should present reproductive barriers to hybridization. However, in the UK, extensive hybridization and introgression between native red deer and introduced Japanese sika deer is currently threatening the red deer with genetic extinction. This project examines two behavioral mechanisms behind this hybridization by testing species discrimination in male-male competition and mate choice in the context of reproductive calls. The ?male-male competition hypothesis? states that males will act more aggressively towards conspecific calls and least aggressively towards heterospecific calls. The ?female mate choice hypothesis? states that females will be more attracted to conspecific calls and least attracted to heterospecific calls. These hypotheses are being tested using playback experiments that broadcast male reproductive vocalizations of red, sika, and hybrid deer to wild and captive red and sika deer while their behavioral reactions (attraction and aggression) are recorded. Differences in reactions between the sexes or species will point to weaknesses in reproductive barriers and potential sources of hybridization and introgression. Experiments are being run on wild deer in the UK and in controlled captive environments at deer farms in the UK, France, and New Zealand. Additionally, more fine-scale female choice decisions involved in hybridization are being examined in France using playbacks of synthetic calls to females with synchronized estrous periods. No species discrimination experiments of this type have been carried out on mammalian species and thus the study results will provide a baseline for understanding the role of vocalizations in mammal hybridization. The PI will bring this important knowledge back to the US where it can be applied both locally and globally to a wide variety of interspecific interactions and hybridizations. The goal is to use this knowledge to implement behavior-focused conservation efforts aimed at stemming hybridization. Additionally, after this fellowship the PI plans to teach and conduct research at a US university where her experience, skills, and collaborations will be shared with US colleagues and students.
