title: The probability of improvement in Fisher's geometric model: a probabilistic approach.
abstract: Fisher developed his geometric model to support the micro-mutationalism hypothesis which claims that small mutations are more likely to be beneficial and therefore to contribute to evolution and adaptation. While others have provided a general solution to the model using geometric approaches, we derive an equivalent general solution using a probabilistic approach. Our approach to Fisher's geometric model provides alternative intuition and interpretation of the solution in terms of the model's parameters: for mutation to improve a phenotype, its relative beneficial effect must be larger than the ratio of its total effect and twice the difference between the current phenotype and the optimal one. Our approach provides new insight into this classical model of adaptive evolution.
authors.affiliation: The Department of Molecular Biology and Ecology of Plants, The George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel. Electronic address: yoavram@post.tau.ac.il.
authors.forename: Yoav
authors.initials: Y
authors.lastname: Ram
authors.affiliation: The Department of Molecular Biology and Ecology of Plants, The George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel.
authors.forename: Lilach
authors.initials: L
authors.lastname: Hadany
mesh_terms: D019143:Evolution, Molecular; D005828:Genetics, Population; D008957:Models, Genetic; D008962:Models, Theoretical; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D011336:Probability
keywords: Fitness landscape; Mathematical models; Mutations; Population genetics