Research Article

The Silent Cooperator: An Epigenetic Model for Emergence of Altruistic Traits in Biological Systems

Figure 1

Silent genes: gene expression is often dependent on environmental factors. At their absence, the gene will stay unexpressed, although it can still be inherited and, in certain cases, spread in a population. The initial and terminal states here could represent low/high temperature, pH, or any combination of environmental triggers required for the activation of the gene in hand.
(a) Appearance of a cooperative gene (C) in the population that is always expressed, at any environmental condition
(b) Appearance of a gene (S) that requires a future state of the environment to be expressed. Till then, the gene carriers act as defective (D)