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

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

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Asexual populations experiencing random genetic drift can accumulate an increasing number of deleterious mutations, a process called Muller's ratchet. We present here diffusion approximations for the
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An analysis of mutation accumulation in finite, asexual populations shows that by modeling discrete individuals, a necessary condition for mutation-selection balance is often not met and under this condition, a sexual population may be able to survive longer, than previously estimated.
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