COMPENSATING FOR OUR LOAD OF MUTATIONS: FREEZING THE MELTDOWN OF SMALL POPULATIONS

• DOI: 10.1111/j.0014-3820.2000.tb00693.x
• Publication Date: 2007-05-09T17:20:26Z
• Authors: Art Poon; Sarah P. Otto
• Keywords: Genetic load; Extinction (optical mineralogy); Mutation Accumulation; genetic model; Small population size; Effective population size; Pleiotropy

Abstract We have investigated the reduction of fitness caused by fixation new deleterious mutations in small populations within framework Fisher's geometrical model adaptation. In model, a population evolves an n‐dimensional character space with adaptive optimum at origin. The allows us to investigate compensatory mutations, which restore losses incurred other context‐dependent manner. conducted moment analysis supplemented numerical results computer simulations. mean (i.e., expected load) scaled one is approximately n/(n + 2Ne), where Ne effective size. reciprocal relationship between load and implies that unlikely cause extinction when there broad scope for except very populations. Furthermore, dependence on n pleiotropy plays large role determining risk Differences similarities our those previous study effects are explored. That predictions this qualitatively different from studies ignoring we must be cautious predicting evolutionary fate additional data nature critical importance.