Environmental Biology, General Biology, Population Biology, Evolutionary Ecology
My primary research focus is the impact of the environment (physical, biotic, or social) on mate choice and sexual selection. Currently, my wife, Ann Pratt, my Ph.D. advisor, Donald J. Shure, and I have two study insect systems that we have now studied for over 30 years (work on each began in 1979). These are (1) mate choice and the evolution of ethological isolation in the soldier beetle, conducted every autumn in the foothills and mountains of northern Georgia (Cornelia, Helen, Hiawassee, Clayton), and (2) territorial behavior of the seed bug on the granite outcrop, Arabia-Davidson Mountain, near Lithonia, Georgia. Currently, we are addressing questions that require multi-year data sets. For instance, in the soldier beetle we are documenting the repeated appearance and disappearance of assortative mating by wing spot length (i.e., beetles with a locality behaving as two species for a few years then reverting to behaving as a single species). In the seed bug, we are looking at the impact of climate variability on the abundance of the bug and in turn how abundance affects mating dynamics and interspecific competition for host plant seeds. Ann and I continue to work on a variety of fiddler crabs species in the Virgin Islands, Bahamas, and along the Atlantic coast from the Florida Keys to Cape Cod. We are especially interested in factors that favor smaller or larger claws (the mass of the single male claw can be 60% of that of the rest of the body). We have identified habitat, density, and presence of competing fiddler crab species as important factors possibly affecting the development and level of selection on claw size and shape.