The role of sex separation in neutral speciation

TL;DR

This paper extends a neutral speciation model to include separate sexes, showing that sex separation reduces the number of species formed but results in fewer, more abundant species.

Contribution

It introduces a sex-separated version of a topopatric speciation model, highlighting differences from hermaphroditic populations.

Findings

Speciation occurs under similar conditions with sex separation.

Number of species decreases compared to hermaphroditic models.

Fewer species tend to be more abundant.

Abstract

Neutral speciation mechanisms based on isolation by distance and sexual selection, termed topopatric, have recently been shown to describe the observed patterns of abundance distributions and species-area relationships. Previous works have considered this type of process only in the context of hermaphrodic populations. In this work we extend a hermaphroditic model of topopatric speciation to populations where individuals are explicitly separated into males and females. We show that for a particular carrying capacity speciation occurs under similar conditions, but the number of species generated decreases as compared to the hermaphroditic case. Evolution results in fewer species having more abundant populations.