The basic problem confronting theoretical ecology (like any theoretical science) is to hypothesize structures, processes, and interactions, and to derive their consequences. We focus on ecological patterns related to population and community dynamics, starting from a conceptual basis that asks how the individual processes of birth, death, and development determine population growth, distribution, and interactions with the environment. These individual-level processes ultimately determine population increase or decline, stability or instability, persistence or extinction, and at a larger scale the structure of entire communities. We consider cases where individuals are characterized by age, body size, developmental stages, infection status, genotype, or spatial location.
We utilize a variety of mathematical models and methods, from stochastic processes, bifurcation theory, matrix algebra, and sensitivity analysis. An important contribution of our research is the development of new analytical and computational methods for the analysis of population dynamics, including sensitivity analyses for population projection models and ecological and evolutionary bifurcation analysis for physiologically structured models. Our research is not taxonomically restricted, and includes plants, animals, and humans.
As always, our theoretical research is inspired by, and provides insight into, applied and empirical problems. Our network of collaborations addresses such problems as the effects of climate change on Antarctic seabirds, how genetic variability and plasticity affects the spread of malaria, how the harvesting of marine fish communities affect population persistence and harvesting yield, and how changes in population structure affect healthy longevity in contemporary human populations.
Individual stochasticity and population heterogeneity in plant and animal demography. An ERC Advanced grant that addresses the role of individual stochasticity and inter-individual heterogeneity in plant and animal demography. The project is developing new models, extending the techniques of demographic analysis, and analysing field and laboratory data.
A NWO Open funded project. Lifetime reproductive output is an important fitness component and reflects the entire life history of the organism (growth, development, survival, and reproduction). This project is developing new theoretical models for lifetime reproduction and applying them to data on plants, animals, and humans.
Eco-evolutionary dynamics of community self-organization through ontogenetic asymmetry. An ERC Advanced grant that investigates the evolutionary and ecological consequences of differences among individuals associated with the differences in their life history stage for population dynamics and life history evolution. Such individual differences translate into asymmetric interactions between individuals in different stages of their life history, for example, asymmetric competition for resources between juveniles and adults. In turn, these asymmetric interactions play important roles in the self-organization of ecological communities and the evolution of life cycle complexity.