image: The figure illustrates evolution on a rugged fitness landscape. Once reaching a local peak, improving fitness necessitates gaining a deleterious mutation (leading, initially, to lower fitness), followed by a beneficial one. In the work of Guo et al. such dynamics are shown to lead to dramatically slow evolutionary trajectories, where fitness constantly increases but with an ever decreasing rate. This material relates to a paper that appeared in the July 31st, 2019, issue of Science Advances, published by AAAS. The paper, by Y. Guo at Harvard University in Cambridge, MA, and colleagues was titled, "Stochastic tunneling across fitness valleys can give rise to a logarithmic long-term fitness trajectory." view more
Credit: Equinox Graphics