Van der Waals-Zeeman Colloquium
Tuesday, 17 Apr 2007, 16:00h
Darwinian walks in empirical fitness landscapes
Dr. Sander Tans
FOM Instituut AMOLF, Amsterdam
Despite its theoretical simplicity, and decades of revolutionary genetic and molecular progress, the process of evolution still presents many mysteries. How can complex systems arise step-by-step? What are the required conditions? What limits the rate? Motivated by these open questions we aim to develop approaches that are both reductionist and experimental. We have started by empirically reconstructing fitness landscapes, which in turn allow us to evaluate the multitude of mutational paths towards a novel cellular function. I will discuss two key functional classes: a new catalytic activity, and a new molecular interaction. The resulting landscapes reveal both constrained and adaptive paths, and also uncover underlying mechanisms. Whether the observed dynamics break down when the systemís complexity is further increased can only be determined through future studies.