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Published on: March 16, 2014
Homoplasy and adaptation in the atelid postcranium
1Institute of Human Origins, Arizona State University, Tempe 85287-4101, USA. cal.iho@asu.edu
American Journal of Physical Anthropology
|May 6, 1999
Summary
Homoplasy, or similar traits evolving independently, is common in primate evolution. This study reveals parallel adaptations in atelid monkey postcrania, driven by positional behaviors and environmental pressures, overwhelming phylogenetic signals.
Area of Science:
- Primate Phylogenetics
- Evolutionary Biology
- Comparative Anatomy
Background:
- Homoplasy is a frequent occurrence in phylogenetic studies but seldom the primary focus.
- Understanding homoplasy is crucial for accurate evolutionary reconstructions, especially in diverse groups like primates.
Purpose of the Study:
- To investigate the patterns and underlying causes of homoplasy within the Atelidae family of New World monkeys.
- To analyze postcranial characters and their evolution across different phylogenetic hypotheses for atelids.
Main Methods:
- Mapping of postcranial characters from Ford's analyses onto alternative phylogenetic trees of Atelidae.
- Examination of phylogenetic signal in relation to parallel adaptations and behavioral regimes.
Main Results:
- Pitheciines do not form a monophyletic group due to shared traits with atelines resulting from hind limb suspensory postures.
- Homoplastic characters in postcranial data suggest parallel adaptations to climbing and suspensory behaviors, potentially overwhelming phylogenetic signals.
Conclusions:
- Parallel adaptations driven by positional behavior and South American environmental pressures are significant sources of homoplasy in atelid phylogeny.
- Homoplasy can dominate data partitions influenced by specific behavioral patterns, impacting evolutionary interpretations.
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