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I am broadly interested in both how selective pressures have shaped behavioral traits and the underlying physiological mechanisms that lead to individual differences in behavior.


The focus of my research is the effects of hormones and social interactions on spatial cognition and adult neurogenesis (new nerve growth), using rats as a model system. We have shown that low testosterone levels impair adult neurogenesis and we have begun to test how other hormones (e.g., prolactin) and social interactions (e.g., sexual and agonistic) influence neurogenesis. The function of these new neurons remains controversial, and we have begun to examine the effects of testosterone on spatial learning and memory using a variety of maze tasks. We have shown that elevated testosterone can improve spatial memory, but the link to neurogenesis remains to be demonstrated. Finally, we are also examining levels of neurogenesis in wild populations of meadow voles. Research in my laboratory has implications for the treatment of a variety of neurodegenerative diseases, and students working with me gain practical experience conducting research projects involving a wide range of techniques: behavioral testing, surgical techniques, immunohistochemistry, hormone assays, and microscopy. The courses I teach involve hands-on laboratory exercise and a variety of discussion and lecture approaches to explore the biological complexity of animals: Animal Physiology, Comparative Vertebrate Biology, Sexual Selection, Endocrinology, and Animal Behavior.