Natural and sexual selection on many loci

Area of Science:

• Population Genetics
• Evolutionary Biology
• Quantitative Genetics

Background:

• Understanding the interplay of selection, mating systems, and recombination is crucial for predicting evolutionary trajectories.
• Existing models often focus on specific scenarios, limiting comprehensive analysis of complex genetic systems.

Purpose of the Study:

• To develop a unified mathematical framework for analyzing the effects of selection, nonrandom mating, and recombination on multiple autosomal loci.
• To provide accurate approximations for allele frequency and linkage disequilibrium dynamics, particularly under weak selection.
• To investigate the coevolution of male traits and female preferences within this framework.

Main Methods:

• Development of exact recursions to model the dynamics of allele frequencies and linkage disequilibria.
• Derivation of simplified approximations for linkage disequilibria under weak selection relative to recombination.
• Application of the framework to analyze existing models of natural and sexual selection.

Main Results:

• The developed method accurately describes the effects of selection, nonrandom mating, and recombination on an arbitrary number of autosomal loci.
• Weak-selection approximations provide valuable insights into linkage disequilibria among multiple loci.
• New results on the coevolution of male traits and female preferences reveal that indirect selection forces are generally weak.

Conclusions:

• The new method offers a versatile tool for studying complex evolutionary processes in population genetics.
• Indirect selection acting on preference loci is unlikely to be a dominant force in the evolution of mating preferences.
• The findings contribute to a deeper understanding of the genetic basis of sexual selection and trait evolution.