Exploring morphological generality in the Old World monkey postcranium using an ecomorphological framework.

Area of Science:

• Primate Paleontology
• Functional Morphology
• Ecomorphology

Background:

• Primates, despite ecological dependence on trees, inhabit diverse environments.
• A generalized primate skeleton facilitates locomotor flexibility and other functions.
• Understanding skeletal adaptations to habitat and locomotion is key to primate evolution.

Purpose of the Study:

• To explore associations between habitat, locomotion, and forelimb morphology in cercopithecids (Old World monkeys).
• To contextualize primate skeletal ecomorphological patterns with other mammals.
• To investigate modifications of the ancestral arboreal 'bauplan' for terrestrial or varied arboreal substrates.

Main Methods:

• Functional morphological analyses of primate forelimbs.
• Phylogenetic comparative techniques.
• Ecomorphological variation analysis in guenons (Chlorocebus and Cercopithecus).
• Comparison of cercopithecid humerus morphology with felids, suids, and bovids.

Main Results:

• Terrestrial Chlorocebus species retain general guenon form with species-specific terrestrial modifications.
• Cercopithecus species show adaptation to different arboreal modes.
• Forelimb variation in guenons is largely stochastic, with fewer traits having strong functional signals.
• Cercopithecid humerus morphology shows habitat signals but with considerable overlap between groups.
• Phylogenetic correction reduced model discriminatory power, indicating phylogeny's ecomorphological importance.

Conclusions:

• The generalized primate postcranium is crucial, with forelimb variation influenced by both stochastic and functional factors.
• Ecological dependence on trees, multiple forelimb functions, and geographic distribution contribute to morphological overlap.
• Phylogeny, like allometry, contains significant ecomorphological information and should be considered in analyses.