For many years, my research programs focused on learning and cognition in an evolutionary context. Most experiments were carried out in laboratory settings designed to simulate problems animals face in nature. In one line of work, we used operant conditioning techniques to investigate cryptic prey detection. Publications in this program have demonstrated that apostatic effects of predation can produce balanced polymorphism and promote the appearance of new morphs, and background heterogeneity can also play a significant role. In a second set of experiments, we investigated the remarkable spatial memory abilities of Clark's nutcrackers when recovering their cached pine seeds. In our third line of work, Alan Bond and I looked at the evolution of learning in social species, comparing highly social pinyon jays with much less social scrub jays and nutcrackers. Our research has integrated psychological and ecological approaches to behavior to develop a comprehensive picture of how the cognitive abilities of animals function adaptively in the context of their natural history.
I have retired from the University of Nebraska and am no longer involved in teaching or research. Now I have time to return to my interest in photography -- particularly nature photography, including macro and landscape.
PDF copies of my publications are available through the