OF MATHEMATICAL & STATISTICAL SCIENCES
UNIVERSITY OF ALBERTA
MONDAY, January 19, 2004
Dr. Erik Noonburg
Department of Biological Sciences
University of Alberta
Resource allocation in variable environments
Dynamic energy budget models describe the allocation of resources by an individual organism to growth, maintenance, development, and reproduction. These models provide a mechanistic link from individual-level processes to population dynamics and life history evolution. However, allocation priorities can not be observed directly—only the results (e.g. change in mass, maturation time) can be measured empirically. One way to probe the allocation rules of a species is to observe the responses of individuals to variation in the environment and compare them to model predictions. I will present a combination of modelling and empirical results from two studies. First, I will use growth and fecundity data from the waterflea Daphnia pulex to distinguish alternative models for allocation priorities under variable food conditions. Second, I will use a life history model to predict the optimal allocation response to changing food and predation risk, and compare the predictions with empirical data from the aquatic midge Chironomus tentans. The tests of model predictions against empirical observations suggest generalizations and limitations of simple allocation models in ecological theory.