Changing the pace of evolution

In biological evolution, the rate of mutations is ''encoded'' by enzymes which can be mutated like any other gene. Inspired by this feature, we present a simple Brownian motion model, in which the temperature itself is a dynamical variable. Intrawell and interwell relaxations occur at different ''temperatures'' and have different dynamics, and the Kramers time becomes asymptotically linear in the barrier height for large heights.