Evolution of genetic potential

Abstract

Organisms empSoy a multitude of strategies to cope with the dynamical environments in which they Save. Homeostasis and physiological plasticity buffer changes within the lifetime of an organism, whiie stochastic developmental programs and hypermutabilaty track changes on longer tamescafes. Ars alternative forag-term mechanism is "gesietie potential"-a heightened sensitivity to the effects of mutation that facilitates rapid evolution to nove! states. Using a transparent mathematica! modeS, we iHustrate the concept of gersetic potential and show that as envirorsmersta! vadabiuty decreasesf the evolving population reaches three distinct steady state conditions: (1) organSsmai fiexibiiity, 2 genetic patesiiia!, arsd (3j genetic robustrsess. As a specific exampie of this concept we examirse ffwctyating selection for hydrophobicsty in a single amirao acid. We see the same three stages, suggesting that envirosirnerstaS fiuctuatkms can produce auele distributions that are distinct not only from those found ynder constant conditions, but also from the transient aHele distributions that arise ursder isoiated selective sweeps. Copyright: ©2005 Meyers et. al.