Documenting homoploid hybrid speciation.

Area of Science:

• Evolutionary Biology
• Speciation Research
• Genetics

Background:

• Homoploid hybrid speciation is difficult to confirm due to diverse hybridization outcomes.
• Establishing homoploid hybrid speciation requires demonstrating that reproductive barriers originate from hybridization.
• This criterion is challenging to meet, necessitating robust methodologies for validation.

Purpose of the Study:

• To describe a common pipeline for identifying candidate genes involved in reproductive isolation in homoploid hybrid speciation.
• To present applications of this pipeline across various plant and animal species.
• To discuss implications for understanding the frequency and duration of homoploid hybrid speciation.

Main Methods:

• A standardized pipeline was utilized to identify candidate genes associated with reproductive isolation barriers in hybrid lineages.
• The pipeline's efficacy was demonstrated through its application to several case studies in plants and animals.
• Functional validation of identified genes was attempted in at least one instance.

Main Results:

• The described pipeline successfully identified candidate genes underlying reproductive isolation in homoploid hybrid species.
• The study provides evidence from multiple plant and animal taxa, showcasing the pipeline's broad applicability.
• Findings suggest that the genetic basis of reproductive isolation in hybrids is often polygenic.

Conclusions:

• Homoploid hybrid speciation may be more frequent and protracted than previously estimated, given the prevalence of admixture.
• The described pipeline offers a valuable tool for future research into the genetic mechanisms of hybrid speciation.
• Further research is warranted to fully elucidate the evolutionary dynamics of homoploid hybrid speciation.