English

A stochastic model of evolution

Probability 2010-11-09 v2 Populations and Evolution

Abstract

We propose a stochastic model for evolution. Births and deaths of species occur with constant probabilities. Each new species is associated with a fitness sampled from the uniform distribution on [0,1]. Every time there is a death event then the type that is killed is the one with the smallest fitness. We show that there is a sharp phase transition when the birth probability is larger than the death probability. The set of species with fitness higher than a certain critical value approach an uniform distribution. On the other hand all the species with fitness less than the critical disappear after a finite (random) time.

Keywords

Cite

@article{arxiv.0909.2108,
  title  = {A stochastic model of evolution},
  author = {Herve Guiol and Fabio P. Machado and Rinaldo B. Schinazi},
  journal= {arXiv preprint arXiv:0909.2108},
  year   = {2010}
}

Comments

6 pages, 1 figure, TeX, Added references, To appear in Markov Processes and Related Fields

R2 v1 2026-06-21T13:45:15.505Z