A COMPARATIVE ANALYSIS OF MORPHOLOGICAL VARIATION PATTERNS IN THE PAPIONINS

Area of Science:

• Evolutionary biology
• Primate morphology
• Quantitative genetics

Background:

• Comparative studies of intraspecific variation are crucial for understanding selection pressures on related species.
• Reconstructing past selection relies on the assumption of stable genetic variance and covariance patterns over time and across species.
• Theoretical models offer contrasting predictions regarding the stability versus lability of variation patterns.

Purpose of the Study:

• To investigate the stability of phenotypic variance and correlation patterns in facial morphology within seven papionin species.
• To determine if variation patterns are consistent across closely related primate species.

Main Methods:

• Utilized 3D coordinates of 12 bony facial landmarks for finite-element scaling analysis to measure local size variation.
• Calculated variances and correlations for local size metrics using pooled sex-specific values.
• Employed vector and matrix correlations with randomization tests to compare variation patterns across species.

Main Results:

• Facial morphology variation and correlation patterns were generally similar across the seven papionin species studied.
• The overall magnitude of correlations was consistent among species, with few significant interspecific differences.
• Similarity in correlation structures did not correlate with phylogenetic relationships among the species.

Conclusions:

• Patterns of variation and correlation in primate facial morphology have remained largely stable within this group.
• This stability supports the reconstruction of past differential selection pressures within the primate clade.
• The findings contribute to understanding evolutionary processes in primate facial development.