Speciation as Pattern Formation by Competition in a Smooth Fitness Landscape

TL;DR

This paper models speciation as a pattern formation process driven by competition in a smooth fitness landscape, revealing conditions under which speciation occurs and demonstrating the importance of interaction range.

Contribution

It introduces an analogy between biological speciation and chemical pattern formation, providing analytical conditions for speciation in the Eigen model with competition.

Findings

Speciation occurs with short-range interactions

No speciation with normal diffusing inhibitors

Analytical conditions match numerical simulations

Abstract

We investigate the problem of speciation and coexistence in simple ecosystems when the competition among individuals is included in the Eigen model for quasi-species. By suggesting an analogy between the competition among strains and the diffusion of a chemical inhibitor in a reaction-diffusion system, the speciation phenomenon is considered the analogous of chemical pattern formation in genetic space. In the limit of vanishing mutation rate we obtain analytically the conditions for speciation. Using different forms of the competition interaction we show that the speciation is absent for the genetic equivalent of a normal diffusing inhibitor, and is present for shorter-range interactions. The comparison with numerical simulations is very good.