Assessing when chromosomal rearrangements affect the dynamics of speciation: implications from computer simulations

Area of Science:

• Evolutionary genetics
• Speciation genomics

Background:

• Inversions are studied for their role in speciation, with recent models highlighting their adaptive significance and recombination suppression.
• The impact of inversions on genome-wide divergence dynamics during speciation remains incompletely understood.

Purpose of the Study:

• To review the framework of "genome-wide congealing" in speciation.
• To examine how inversions, through genetic hitchhiking, can hasten genome-wide congealing.
• To use simulation models to assess conditions and magnitudes of inversion-driven speciation.

Main Methods:

• Review of speciation genomics frameworks.
• Development and application of simulation models to study inversions' effects on genome-wide divergence.

Main Results:

• Inversions most effectively promote speciation when fixed early between populations, followed by adaptation involving numerous genes with minor fitness effects.
• Simulation results quantify the conditions and magnitudes under which inversions accelerate genome-wide congealing.
• The study identifies key aspects of inversions' roles in speciation, including geographic context, facilitation of divergence, and biased divergence patterns.

Conclusions:

• Inversions can significantly accelerate speciation with gene flow under specific conditions.
• Further research is needed on the influence of underdominance and epistasis within inversions.
• Empirical validation of inversions' central role in facilitating speciation presents significant challenges.