Hybridization can promote adaptive radiation by means of transgressive segregation

Authored by Kotaro Kagawa, Gaku Takimoto

Date Published: 2018

DOI: 10.1111/ele.12891

Sponsors: Japanese Society for the Promotion of Science (JSPS)

Platforms: Java

Model Documentation: Other Narrative Mathematical description

Model Code URLs: https://datadryad.org/resource/doi:10.5061/dryad.4cf2p

Abstract

Understanding the mechanisms of rapid adaptive radiation has been a central problem of evolutionary ecology. Recently, there is a growing recognition that hybridization between different evolutionary lineages can facilitate adaptive radiation by creating novel phenotypes. Yet, theoretical plausibility of this hypothesis remains unclear because, for example, hybridization can negate pre-existing species richness. Here, we theoretically investigate whether and under what conditions hybridization promotes ecological speciation and adaptive radiation using an individual-based model to simulate genome evolution following hybridization between two allopatrically evolved lineages. The model demonstrated that transgressive segregation through hybridization can facilitate adaptive radiation, most powerfully when novel vacant ecological niches are highly dissimilar, phenotypic effect size of mutations is small and there is moderate genetic differentiation between parental lineages. These results provide a theoretical basis for the effect of hybridization facilitating adaptive radiation.

Tags

Individual-based model Evolution selection population sympatric speciation Extinction Colonization Ecological speciation Adaptive radiation Cichlid fish Evolutionary simulation Hybridization Transgressive segregation Homoploid hybrid speciation Genetic architecture Darwins finches