|Document Type:||Journal Article|
|Title:||Life history traits and effective population size in species with overlapping generations revisited: the importance of adult mortality|
|Author:||Robin S. Waples|
|Keywords:||effective populaton size,adult survival,generation length,age at maturity,variance in reproductive success|
The relationship between life-history traits and the key eco-evolutionary parameters Ne and Ne/N is revisited for iteroparous species with overlapping generations, with a focus on the annual rate of adult mortality (d). Analytical methods based on populations with arbitrarily long adult lifespans are used to evaluate the influence of d on Ne, Ne/N, and the factors that determine these parameters: adult abundance (N), generation length (T), age at maturity (alpha), the ratio of variance to mean reproductive success in one season by individuals of the same age (phi), and lifetime variance in reproductive success of individuals in a cohort (Vk*). Although the resulting estimators of N, T, and are upwardly biased for species with short adult lifespans, the estimate of Ne/N is largely unbiased because biases in T are compensated for by biases in Vk* and N. For the first time, the contrasting effects of T and Vk* on Ne and Ne/N are jointly considered with respect to d and phi. A simple function of d and alpha based on the assumption of constant vital rates is shown to be a robust predictor (R2 = 0.78) of Ne/N in an empirical dataset of life tables for 63 animal and plant species with diverse life histories. Results presented here should provide important context for interpreting the surge of genetically-based estimates of Ne that has been fueled by the genomics revolution.
|Theme:||Recovery and rebuilding of marine and coastal species|
Develop methods to use physiological, biological and behavioral information to predict population-level processes.
Characterize the population biology of species, and develop and improve methods for predicting the status of populations.
Waples, R.S. 2016. Life history traits and effective population size in species with overlapping generations revisited: the importance of adult mortality. Heredity (published online 8 June 2016; doi:10.1038/hdy.2016.29).