Research

The question that drives my research is, "how do chemicals control our social lives?" I am interested in how endocrine and exocrine chemical signals modulate social behavior in territorial animals, and I approach this research from an integrative and comparative perspective. My research integrates the fields of chemical and behavioral ecology with neuroendocrinology and I use lizards as an animal model. My current animal models include several species from the genus Sceloporus and Anolis carolinensis.

I examine the role of arginine vasotocin in mediating territorial and reproductive interactions through the chemical sensory system. My current work focuses on the neural processes involved in establishment and maintenance of dominant-subordinate relationships and acquisition of mating opportunities. My previous work demonstrated the important role of chemical signals in mediating territorial space use in the field, and emphasized species and individual differences in chemical signal composition. My research integrates behavioral assays in the field and lab with techniques from neuroethology and analytical chemistry (gas and liquid chromatography/mass spectrometry) to understand how dynamic changes in social relationships are chemically-mediated, either internally via neurotransmitters or externally via chemical communication.

Above photo: Sceloporus jarrovii, Yarrow's Spiny Lizard, in the Chiricahua Mountains of southern Arizona. This male is showing off the femoral pores on its left thigh. These femoral pores secrete chemical signals used in social and territorial communication. These are the chemical signals I study.

I research how chemical signals and specific elements within these signals impact competitive behavior and territorial space use using Sceloporus lizards.

A territorial encounter: two adult Sceloporus jarrovii males in a territorial bout of aggression

A mating encounter: an adult male Sceloporus undulatus engaged in a neck bite with a female.

I use behavioral playbacks in the field to ask about the impact of chemical signals on space use, and the relative roles of signaler or receiver physiology and environment in shaping chemical communication. I also combine techniques from chemical ecology in the field with chemical analyses in the lab using gas-chromatography/mass-spectrometry (GCMS) to examine the behavioral and functional significance of pheromone candidates that we recently found in Sceloporus femoral gland secretions, but were previously unknown to be produced by lizards.

Finally, I borrow phylogenetic comparative methods and analytical techniques from microbiology to ask about evolutionary constraints on chemical communication. These studies focus on the diverse habitats Sceloporus lizards live in, as well as the microbial communities inhabiting lizard scent glands.