A general framework for the analysis of phenotypic trajectories in evolutionary studies

Area of Science:

• Evolutionary biology
• Quantitative genetics
• Paleontology

Background:

• Understanding phenotypic change is crucial for evolutionary studies.
• Existing methods for analyzing phenotypic variation are limited to pairwise comparisons.
• A need exists for methods to compare evolutionary sequences across multiple levels.

Purpose of the Study:

• To present a general analytical procedure for quantifying and comparing patterns of phenotypic evolution.
• To define phenotypic evolution as a trajectory in multivariate phenotype space.
• To statistically assess the concordance and repeatability of evolutionary patterns across taxa.

Main Methods:

• Quantifying attributes of phenotypic trajectories (size, direction, shape).
• Statistically comparing these trajectories across taxa.
• Using a summary statistic to determine concordance across multiple taxa.

Main Results:

• The approach provides a quantitative description of differing phenotypic evolution patterns.
• It offers a statistical assessment of the repeatability of evolutionary responses to selection.
• The method is applicable to various evolutionary processes like plasticity, selection, and adaptation.

Conclusions:

• The developed procedure offers a robust framework for analyzing complex phenotypic evolution.
• It enhances the ability to compare evolutionary trajectories and understand convergence or divergence.
• The method was illustrated using fossil lineages of Globorotalia, demonstrating its practical application.