Senescence–the progressive age-dependent decline in performance–occurs in most
organisms. There is considerable variation in the onset and rate of senescence between
and within species. Yet the causes of this variation are still poorly understood, despite being
central to understanding the evolution of senescence. Long-term longitudinal studies on wild
animals are extremely well-suited to studying the impact of environmental and individual
characteristics (and the interaction between the two) on senescence, and can help us to …