Sergio Vallina

Sergio Vallina

Postdoctoral Fellow

Marine Biologist

The self-organized structure, evolutionary dynamics, and stability to climatic fluctuations of marine food webs are the main focus of my current research. Oceanographers have only recently started to address these key aspects of theoretical ecology, with a more rigorous and mathematically formal approach, to marine ecosystems. Until very recently, most of the effort has been mainly directed towards more general biogeochemical modelling based on simple ecosystem models.

Simple biogeochemical models are not always capable of resolving the complex dynamics observed in real food web networks. The level of species diversity, the sign and strength of interaction between the species, the adaptive evolution of species-traits and interactions, are all going to affect the structure, functioning, productivity, and stability of ecosystems. My research aims at studying these fundamental aspects of the dynamics of marine ecosystems by using food web models of several degrees of complexity, built on first principles and trade-off rules.

My research is structured along 3 complementary lines of ecological theory. First, how marine ecosystems self-organize due to biophysical constrains and niche partitioning, and how the resulting food web structure affects the functioning and overall production of the ecosystem. Second, how changes in food web complexity will affect ecosystem stability to climatic perturbations. Third, how the evolution and adaptation of species-traits affects the fitness of the species present (or newcomers) in the community, and therefore to asses the impact of adaptive dynamics on food web structure, functioning and stability.

I am currently a Marie Curie Fellow in a joint project between the Massachusetts Institute of Technology (MIT) and the Marine Sciences Institute of Barcelona (CSIC). Previously, I was a postdoc at the University of East Anglia (UK). I did my PhD at the Instituto de Ciencias del Mar (CSIC).