When Senescence is Optimal and When it is Not

Annette Baudisch, Max Planck Institute for Demographic Research

The age-trajectories of fertility and mortality are the two basic schedules in demography and the two fundamental functions in life-history biology and evolutionary theory. Understanding the evolutionary-demographic forces that shape the age-trajectories of fertility and mortality is therefore a topic of the most profound interest and importance in demography and biology. The main purpose of this research is to investigate the conditions that differentiate between the evolution of senescent versus non-senescent life-history strategies. A senescent strategy is associated with increasing mortality and decreasing fertility with age. A non-senescent strategy is associated with constant or decreasing mortality and constant or increasing fertility with age.