Evolutionary Ecology

Another of my primary interests is understanding the relationship between an organism's phenotypic traits and the environment. How organisms adapt and diversify in their habitat is a long-standing question in biology. My work has predominately focused on lizards, specifically Liolaemus from South America and the Australian agamid radiation, Amphibolurinae. I am certainly not restricted to these groups and have a broad interest in understanding ecomorphological patterns across such disparate groups as herps, birds, mammals, plants, and insects. Identifying general patterns among these important groups will greatly increase our understanding of the natural world.

Liolaemus ecomorphology

Liolaemus or South American swifts are the second most species rich genus of lizards in the world. They occupy almost every habitat available in southern South America and are quite diverse morphologically making them an ideal candiate for a detailed study of the relationship between ecology and morphology.
Liolaemus gracilis, Chubut, Argentina
Liolaemus fitzingeri, Chubut, Argentina
Liolaemus chacoensis, Anillaco, Argentina
Liolaemus tenuis, Altos del Lircay, Chile
Liolaemus kingii, Chubut, Argentina
Liolaemus manueli, Diego de Almagro, Chile

My recent work has demonstrated that Liolaemus species exhibit a unique relationship between ecobehavior and morphology. Fabian Jaksic and colleagues in 1980 found there was no consistent relationship between habitat and morphology among 12 species of central Chilean species of Liolaemus. Numerous previous studies on squamate reptiles have demonstrated a relationship between morphology and structural microhabitat characteristics. Among 25 species of Liolaemus sampled throughout their range indicates that there is a significant relationship between predator escape behavior and morphology, and not structural habitat variables. These results suggest that alternative behaviors used by different species essentially greatly reduces the impact of selective forces acting to change morphology, a phenomenon recently described by Huey et al. (2003) as the "Bogert effect". Additional taxon sampling and performance data are critical to further test these evolutionary hypothesis and are the subject of future studies.