André de Roos

External Professor

I received my PhD from the University of Leiden where I was supervised by Hans Metz and Odo Diekmann. After post-doctoral positions in Canada (University of Calgary) and Scotland (Strathclyde University, Glasgow) I moved to the University of Amsterdam.

My research includes more mathematical as well as more ecological studies using a class of models, known as physiologically structured population models. The basic characteristic of these models is that state concepts are introduced at both the individual and the population level and that model formulation is entirely restricted to individual-level, life history processes. The dynamics of the population simply result from keeping book of all individual-level changes. Initially I primarily focused on developing numerical tools to analyse these models, moving on to applying these models to solve ecological questions later on. At present, my interests still span a broad variety of topics, ranging from on the one hand gaining a deeper understanding about ecological communities in which size structure plays a role to developing mathematical concepts for modelling biological populations and analysing biological models.

In particular I have used physiologically structured population models to study the relationship between processes at the level of individual life history and the dynamic patterns at the population level, probing the validity of classical, population dynamic theory, which is based on unstructured models. An important topic concerns the consequences of individual energetics, such as size-dependent feeding, growth and reproduction for population and community dynamics and in particular the feedback of these dynamics on the realised life history of individual organisms. I have collaborated with experimental and field ecologists to test the theoretical predictions on, among others, zooplankton and fish. The results of my research often seem counter-intuitive, like for example the finding that recovering piscivorous fish stocks may be best promoted by harvesting the piscivore’s main prey species. Together with Lennart Persson I published in 2013 a Princeton Monograph in Population Biology on the relationship between ontogenetic development and community dynamics.

More recently I have also broadened my studies to include more evolutionary questions, for example, about the evolution of life cycle complexity and the factors that promoted the evolution of metamorphosis in animal species.