LONG-TERM CORRELATED RESPONSE, INTERPOPULATION COVARIATION, AND INTERSPECIFIC ALLOMETRY

Area of Science:

• Evolutionary biology
• Quantitative genetics

Background:

• Understanding evolutionary processes requires models of correlated trait evolution.
• Selection can be partitioned into stabilizing and directional components.

Purpose of the Study:

• To analyze a model of long-term correlated evolution for multiple quantitative characters.
• To investigate how short-term and long-term selection responses differ.

Main Methods:

• Developed a model partitioning selection into stabilizing and directional components.
• Assumed stabilizing selection is less variable than directional selection among populations.
• Derived formulas for interpopulation covariation and interspecific allometry.

Main Results:

• Short-term trait responses to selection depend on genetic correlations.
• Long-term trait responses are determined by fitness functions, independent of genetic and phenotypic correlations.
• Formulas for covariation and allometry depend on the stabilizing selection intensity matrix.

Conclusions:

• Selection's impact on trait evolution differs significantly between short and long timescales.
• Genetic and phenotypic correlations are crucial for short-term adaptation but not long-term evolutionary trajectories.
• The stabilizing selection intensity matrix is key for understanding interpopulation and interspecific patterns.