Adaptation in simple and complex fitness landscapes

TL;DR

This paper reviews deterministic mutation-selection models for asexual populations, exploring simple and complex fitness landscapes, error thresholds, and evolutionary dynamics, with connections to statistical physics and experimental observations.

Contribution

It provides a comprehensive overview of mutation-selection models, including recent extensions to rugged landscapes and evolutionary dynamics, integrating theoretical and experimental perspectives.

Findings

Analysis of error threshold phenomena in simple landscapes

Discussion of fitness correlations in rugged landscapes

Overview of experimental studies on evolutionary dynamics

Abstract

This is an introductory review of deterministic mutation-selection models for asexual populations (i.e., quasispecies theory) and related topics. First, the basic concepts of fitness, mutations, and sequence space are introduced. Different types of mutation-selection dynamics are defined and their relation to problems of statistical physics are outlined. Then the stationary population distribution in simple, single peak fitness landscapes is discussed at length, with particular emphasis on the error threshold phenomenon. Extensions of the theory covering e.g. epistatic interactions, diploid organisms, semiconservative replication and time-dependent fitness peaks are briefly described. A further section is devoted to randomly rugged fitness landscapes, which may display fitness correlations of various degree as well as extended neutral networks. The final two sections address evolutionary dynamics in both rugged and smooth fitness landscapes, and provide a brief overview of pertinent experiments.