Aging is among the most profound of biological phenomena. It potentially influences the biology of animals at all levels; and the deleterious aspects of aging raise intriguing theoretical, empirical, medical, and social problems. Not surprisingly, aging has become a major focus of research. However, most studies have focused on aging in laboratory stocks of inbred animals, and very few studies have attempted to determine whether the resulting findings apply to animals in natural populations. This proposal investigates aging in natural populations of lizards. Huey and Dunham will gather information on how the physiology and behavior of these lizards change as they grow old. Then they will determine whether declining performance of old lizards leads to increased risk of death. By comparing patterns of aging in two populations, they will also test an evolutionary hypothesis on the timing of aging. This will be the first comprehensive study of aging in any natural population. This multidisciplinary approach will be a useful advance and further a general understanding of the biology of aging.
