My research philosophy has several major themes. First, I construct theories and test them by conducting observational and experimental field studies. Second, I apply a reductionist approach to understand higher level processes, e.g., can community ecology be understood by population process and population processes in turn be understood by behavioral/physiological processes. Finally, I attempt to employ my studies of ecological principles to address applied problems (e.g. conservation) and provide insights in other disciplines (e.g., anthropology/archeology).

I have particularly focused on foraging theory as it relates to population dynamics, interspecific competition, predator-prey dynamics and nutrient cycling in ecosystems. I have studied a variety of animals and habitats: mammals, birds, grasshoppers, spiders and brine shrimp in grasslands (Montana), desert shrubland (Australia), boreal forest (Michigan), rainforest (Puerto Rico), tundra (Alaska) and saline lakes (Utah).

Results have furthered conservation and sustainable harvesting. By studying a diversity of herbivores and predators, ecological patterns related to body mass have been explored in varying environments. Findings from these studies have been applied to examine population viability for conservation, pest control programs of herbivores that may be reducing nutrient cycling and thereby, plant production in ecosystems, and prehistoric human hunter-gatherers and how they influenced their environment. Understanding how ecosystems function is of scientific interest. But in a world where human activity threatens ecosystems, understanding their operation is also critical for managing and protecting.