Life histories and Cope's rule from an explicit resource–consumer model based on metabolic theory

Abstract

We explore the consequences of metabolic theory for life histories and life history evolution. We use a mathematical model for an iteroparous species and its resources, taking into account the allometric scaling of consumption, metabolism, and mortality with consumer body mass. Mortality is assumed to be density-dependent, and the dynamics of resources are modeled explicitly. By evaluating life history features in equilibrium populations, we find that in populations that use more or faster growing resources the individuals have a shorter lifespan and a higher mortality, and that individuals in populations with a larger adult body mass have a longer lifespan, a larger number of offspring per female, and a higher biomass density. When we allow the adult body mass to evolve, it increases in time without limits. When we allow the offspring body mass to evolve independently from adult body mass, it becomes smaller. However, when we take into account that larger individuals have larger offspring, both body masses evolve to larger values. These trends result from the allometric scaling of mortality and can be kept in limits by trade-offs other than those included in our model.