The evolution of social interactions changes predictions about interacting phenotypes

Area of Science:

• Evolutionary biology
• Quantitative genetics
• Behavioral ecology

Background:

• Social interactions shape many traits, including courtship and aggression.
• Interacting phenotypes are traits influenced by a social partner's phenotype.
• Existing models treat the interaction rule as a fixed coefficient (ψ).

Purpose of the Study:

• To extend quantitative genetic models of interacting phenotypes.
• To incorporate the interaction coefficient (ψ) as an evolvable trait.
• To investigate how the evolution of the interaction coefficient impacts social trait evolution.

Main Methods:

• Developed extended theoretical models for interacting phenotypes.
• Incorporated the interaction coefficient (ψ) as a variable trait subject to evolution.
• Analyzed the impact of an evolving interaction coefficient on evolutionary dynamics.

Main Results:

• The evolution of the interaction coefficient (ψ) can qualitatively alter predictions.
• The rate and direction of interacting phenotype evolution are sensitive to the evolution of ψ.
• Treating ψ as fixed may lead to inaccurate predictions.

Conclusions:

• The phenotypic response to social partners is not always a fixed rule.
• The evolvability of the interaction coefficient is critical for understanding social evolution.
• Accurate predictions require considering how social interaction rules themselves evolve.