Crossing a fitness valley as a metastable transition in a stochastic population model

  title={Crossing a fitness valley as a metastable transition in a stochastic population model},
  author={Anton Bovier and Loren Coquille and Charline Smadi},
  journal={The Annals of Applied Probability},
We consider a stochastic model of population dynamics where each individual is characterised by a trait in {0,1,...,L} and has a natural reproduction rate, a logistic death rate due to age or competition and a probability of mutation towards neighbouring traits at each reproduction event. We choose parameters such that the induced fitness landscape exhibits a valley: mutant individuals with negative fitness have to be created in order for the population to reach a trait with positive fitness… 

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