Self-destructive cooperation mediated by phenotypic noise

Nature. 2008 Aug 21;454(7207):987-90. doi: 10.1038/nature07067.


In many biological examples of cooperation, individuals that cooperate cannot benefit from the resulting public good. This is especially clear in cases of self-destructive cooperation, where individuals die when helping others. If self-destructive cooperation is genetically encoded, these genes can only be maintained if they are expressed by just a fraction of their carriers, whereas the other fraction benefits from the public good. One mechanism that can mediate this differentiation into two phenotypically different sub-populations is phenotypic noise. Here we show that noisy expression of self-destructive cooperation can evolve if individuals that have a higher probability for self-destruction have, on average, access to larger public goods. This situation, which we refer to as assortment, can arise if the environment is spatially structured. These results provide a new perspective on the significance of phenotypic noise in bacterial pathogenesis: it might promote the formation of cooperative sub-populations that die while preparing the ground for a successful infection. We show experimentally that this model captures essential features of Salmonella typhimurium pathogenesis. We conclude that noisily expressed self-destructive cooperative actions can evolve under conditions of assortment, that self-destructive cooperation is a plausible biological function of phenotypic noise, and that self-destructive cooperation mediated by phenotypic noise could be important in bacterial pathogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biological Evolution
  • Cooperative Behavior
  • Disease Models, Animal
  • Enterocolitis / microbiology
  • Mice
  • Models, Biological*
  • Phenotype
  • Salmonella Infections / microbiology*
  • Salmonella typhimurium / pathogenicity*
  • Salmonella typhimurium / physiology*
  • Stochastic Processes
  • Virulence Factors / physiology


  • Virulence Factors