Sam Houston State University
Director of the Texas Research Institute for Environmental Studies
Department of Biological Science
My main research focuses on ectothermic vertebrates and their unique physiologies as they are influenced by temperature and other environmental factors. These studies have a central theme in comparative physiology in which behavioral and physiological responses and tolerances to temperature are investigated. I am currently working on species-specific difference in temperature dependent physiological rate processes and how these differences may correlate with macroecological patterns of distribution among related species.
Correlates between environmental factors and physiological tolerances are central to an understanding of species distribution and adaptation. An organism's geographic distribution largely results from its range of physiological tolerances and its ability to adjust physiological "set-points" to maximize survival, growth, and reproduction. The idea that species have differential survivorship due to differences in their basic physiological and ecological requirements offers an interesting theoretical context to Invasive Species Biology. Liebig's law of the minimum states that “the distributions of species are governed by the environments factor for which a species has the narrowest tolerance range or least adaptability”. This concept defines my research interests in evaluating the potential success an invasive species may have in exploiting new environmental and out competing endemic species. It is only through such investigation that researchers may offer empirical data and gain a theoretical understanding for the tolerance limits of various plants and animals and how these limits will influence the ecology and distribution of invasive species.