Interest in transient population dynamics is ironically not transient. The utilisation of transients is slowly gaining momentum in applied studies of conservation and management, leading hopefully to more effective strategies for attaining desired goals. Moving from a proximate to an ultimate understanding of transient dynamics requires looking through the lens of evolutionary demography. Transients are a consequence of structured life history, and enable populations to bounce back from certain disturbances. If population growth rate is a measure of fitness of an average life history, then one may reasonably expect that life histories evolve to rebound from disturbances experienced in their evolutionary past. We pick a universal character of life history – age – and explore how demographic quantities (survival and reproduction) over age characterise transient population dynamics of life histories, and how this compares to how they determine stable population growth. This includes new methodology for decomposing components of age as well as population dynamics.
Results/Conclusions
Distributions of survival and reproduction over age (the ‘shape’ of aging) are associated with magnitudes of transient dynamics of those life histories, but the same may not be said of longevity and reproductive lifespan (the ‘pace’ of aging). Life histories tend on average to ‘bounce back’ from exogenous disturbance, and the possibility that transient dynamics play a significant role in life history evolution should not be overlooked.