Demographic noise can lead to spontaneous formation of species

Various theoretical ecologists have studied how competition and differing local conditions lead to speciation, that is, how an initially diverse population evolves into clusters of similar individuals. Past studies have neglected the effect of demographic fluctuations and focused on the effect of the exact way in which the effect of competition decays with (phenotypic) distance. In this paper, the authors show that including the effects of demographic noise leads to the formation of species even when the functional form of the competition is not enough to induce speciation.

References: T. Rogers, A. J. McKane and A. G. Rossberg, 2012 EPL 97 40008
Background: Szabó P, Meszéna G (2006) Limiting similarity revisited Oikos 112(3):612–619