Physics Colloquium: Survival of the Fittest? The Biodiversity Puzzle

Abstract:

Random matrix theory was developed by Wigner and others to describe the horribly complicated interactions of nucleons.  Robert May (famous for his contributions to chaos, among other things) adapted this approach to describe the interactions of creatures in an ecosystem, and used it to prove that a system of randomly interacting creatures does not possess a stable steady-state, unless there are very few interacting species or the interactions are very weak.  This conclusion is in blatant contradiction to the existence of many ecosystems where hundreds of species coexist.  We show how letting the system evolve through species extinction and creation of new species through speciation drives the system to a structured hierarchical system of interactions that circumvents the May theorem and allows for a diverse stable ecocommunity.

Event Organizer: Prof. Ben Svetitsky