Dresden 2011 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
DY: Fachverband Dynamik und Statistische Physik
DY 32: Statistical Physics in Biological Systems III (organised by BP)
DY 32.7: Talk
Thursday, March 17, 2011, 12:15–12:30, ZEU 260
How to cross a fitness valley - A network approach — •Hinrich Kielblock1, Marc Timme1,2, and Stefan Grosskinsky3 — 1Network Dynamics Group, Max Planck Institute for Dynamics and Self-Organization, Göttingen, Germany — 2Bernstein Center for Computational Neuroscience Göttingen, Germany — 3Centre for Complexity Science, University of Warwick, Conventry, UK
How fast does a population evolve from one fitness peak to another in a fitness landscape? This question has recently received much attention as the answer may strongly affect the speed of evolution.
Here we analyze the problem in the stochastic tunneling regime, where almost always almost all individuals are found near one fitness peak but once in a while the population switches to another peak. We derive an analytical expression for this switching time considering finite polulation sizes. We first analyze the dynamics of a population existing in only two different genotypes. The results of such a simple system enable us to derive a formula for an effective mutation rate between the peaks of a fitness valley. This effective rate makes it possible to determine the mean switching times in more complex setups, as e.g. multiple fitness valleys or other structures.