Multilevel selection 1: Quantitative genetics of inheritance and response to selection

Area of Science:

• Evolutionary Biology
• Quantitative Genetics
• Behavioral Ecology

Background:

• Individual interactions are universal in nature and agriculture, influencing population evolution and artificial selection.
• Classical quantitative genetics lacks a comprehensive theory for interactions and multilevel selection.
• Existing theories fail to explain differential trait responses to individual versus group selection.

Purpose of the Study:

• To develop a quantitative genetic framework incorporating interactions and multilevel selection.
• To provide expressions for predicting the response to multilevel selection.
• To explain previously unexplained patterns of trait evolution.

Main Methods:

• Development of a novel quantitative genetic framework.
• Derivation of equations for the response to selection across multiple levels.
• Comparison with classical quantitative genetic theory.

Main Results:

• Individual interactions generate substantial, previously hidden heritable variation.
• Higher levels of selection effectively utilize this hidden variation, yielding positive responses.
• Individual selection can lead to responses in the opposite direction of group selection.

Conclusions:

• The new framework accurately predicts responses to multilevel selection.
• It reconciles discrepancies between individual and group selection outcomes.
• The framework is applicable to both natural and domestic populations.