|Perturbation analysis of longevity|
Longevity is a fundamental demographic property. Human demographers are fascinated by it partly because it describes how long human demographers (among others) live, and partly because it has undergone historically unprecedented increases in the last 200 years. Evolutionary demographers are fascinated by it because it reflects, at least partly, the action of senescence, which for more than half a century has been the canonical problem of life history evolution. Population ecologists are at least mildly interested in it because it summarizes mortality patterns and influences population growth, recovery, and introductions.
My research on longevity uses Markov chain theory to develop new indices of longevity, especially for complex stage-structured (or age x stage-structured) life cycles. Given the indices, I then use matrix calculus to explore the sensitivity and elasticity of longevity to demographic parameters.