# How often does the ratchet click? Facts, heuristics, asymptotics

@article{Etheridge2007HowOD, title={How often does the ratchet click? Facts, heuristics, asymptotics}, author={Alison M. Etheridge and Peter Pfaffelhuber and A. Wakolbinger}, journal={arXiv: Probability}, year={2007} }

The evolutionary force of recombination is lacking in asexually reproducing populations. As a consequence, the population can su! er an irreversible accumulation of deleterious mutations, a phenomenon known as Muller’s ratchet. We formulate discrete and continuous time versions of Muller’s ratchet. Inspired by Haigh’s (1978) analysis of a dynamical system which arises in the limit of large populations, we identify the parameter ! = N" /(Ns · log(N" )) as most important for the speed of…

## 29 Citations

Fluctuations of Fitness Distributions and the Rate of Muller’s Ratchet

- BiologyGenetics
- 2012

This work shows analytically how fluctuations among the fittest individuals propagate to individuals of lower fitness and have dramatically amplified effects on the bulk of the population at a later time.

Dynamic Mutation–Selection Balance as an Evolutionary Attractor

- BiologyGenetics
- 2012

It is found that a surprisingly low fraction of beneficial mutations suffices to achieve stability, even in small populations in the face of high mutation rates and weak selection, maintaining a well-adapted population in spite of Muller’s ratchet.

The spatial Muller’s ratchet: surfing of deleterious mutations during range expansion

- BiologybioRxiv
- 2020

Using simulations, it is shown that the presence of an Allee effect reduces the rate at which clicks occur at the front, and thus reduces the expansion load.

A stochastic model for a single click of Muller's ratchet.

- BiologyJournal of theoretical biology
- 2010

Rare beneficial mutations cannot halt Muller's ratchet in spatial populations
(a)

- BiologyEPL (Europhysics Letters)
- 2018

Based on the relation between the spatial ratchet and directed percolation, a scaling theory incorporating both deleterious and beneficial mutations is developed that is verified by extensive simulations in one and two dimensions.

Sex, fitness decline and recombination – Muller’s ratchet vs. Ohta’s ratchet

- BiologybioRxiv
- 2020

It is asked whether the fitness decline can indeed be stopped if an asexual population turns sexual to become recombining, and whether the alternative explanations to be generally more compelling.

Asymptotic behavior of the rate of adaptation

- Biology, Mathematics
- 2007

If the genome is modeled as continuous, there is no limit to natural selection, that is, the rate of adaptation grows in $N$ without bound.

Joint Prediction of the Effective Population Size and the Rate of Fixation of Deleterious Mutations

- BiologyGenetics
- 2016

A set of equations for the joint prediction of the effective population size and the rate of fixation of deleterious mutations, which are applicable both to sexual and asexual species are provided, and predictions for sexual populations allow for outlining the general conditions where mutational meltdown occurs.

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