Choosing the fittest as a speciation mechanism

TL;DR

This paper presents a model showing that preference for high-fitness mates can promote genetic clustering and facilitate sympatric speciation in populations inhabiting inhomogeneous environments.

Contribution

It introduces a novel model where mate preference for high fitness drives genetic clustering, advancing understanding of mechanisms behind sympatric speciation.

Findings

Preference for high-fitness mates leads to genetic clustering.

Model shows rapid fixation of advantageous alleles.

Supports sympatric speciation through non-random mating.

Abstract

When a population inhabits an inhomogeneous environment, the fitness value of traits can vary with the position in the environment. Gene flow caused by random mating can nevertheless prevent that a sexually reproducing population splits into different species under such circumstances. This is the problem of sympatric speciation. However, mating need not be entirely random. Here, we present a model where the individually advantageous preference for partners of high fitness can lead to genetic clustering as a precondition for speciation. In simulations, in appropriate parameter regimes, our model leads to the rapid fixation of the corresponding alleles.