Trait Evolution in Adaptive Radiations: Modeling and Measuring Interspecific Competition on Phylogenies

Area of Science:

• Evolutionary biology
• Ecological modeling
• Phylogenetics

Background:

• Species interactions are crucial drivers of trait evolution.
• Existing models lack the ability to incorporate interspecific competition.
• Analytical challenges hinder the development of such models.

Purpose of the Study:

• To develop phylogenetic models of trait evolution that incorporate interspecific competition.
• To provide a framework for understanding how competition shapes evolutionary trajectories.
• To test the model's ability to detect competition using comparative data.

Main Methods:

• Development of phylogenetic models of trait evolution including interspecific competition.
• Modeling competition as a force promoting divergence between sympatric species.
• Utilizing approximate Bayesian computation (ABC) for parameter estimation.

Main Results:

• The model predicts trait overdispersion, high phylogenetic signal, elevated trait variance, and slower evolutionary rates.
• Competition reduces correlations between traits.
• The model demonstrates power to detect competition in trees with over 20 species.

Conclusions:

• Interspecific competition significantly impacts trait evolution, leading to divergence.
• The developed model offers a valuable tool for studying the evolutionary effects of competition.
• Evidence suggests competition influenced the evolution of Darwin's finches' bill morphology.