As a scientist, I have always been interested in how animals use and acquire space where they live and breed. Since most animals must compete for space with others of their species, my interest has led naturally to study of animal aggression and competition. My PhD focused on how the social rank of a white-throated sparrow (Zonotrichia albicollis) in a winter dominance hierarchy affected its local movements and likelihood of survival. I have also investigated aggression and breeding among male stripe-backed wrens (Campylorhynchus nuchalis) in Venezuela. But since 1993, my work has focused on territory defense, habitat selection, and breeding behavior of loons. In recent years, I have noticed that my study animals and I have both aged, so my interests have expanded to looking at the impact of aging on behavior (the loons’, not mine). My curriculum vitae (below) givesspecific details regarding my professional career.