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Dissection, MicroCT Scanning and Morphometric Analyses of the Baculum
Published on: March 19, 2017
An analysis of epipubic bone function in mammals using scaling theory
1Department of Biology, University of California, Los Angeles 90024.
Journal of Theoretical Biology
|August 9, 1989
Summary
Epipubic bones in marsupials and monotremes scale differently with mass, suggesting locomotion, not marsupial support, is a primary function influencing their form.
Area of Science:
- Comparative anatomy
- Functional morphology
- Evolutionary biology
Background:
- Epipubic bones are found in metatherians and monotremes.
- Their function, particularly in relation to marsupial support, is debated.
Purpose of the Study:
- To investigate the allometric scaling of epipubic bone dimensions in metatherians and monotremes.
- To test hypotheses regarding the functional significance of epipubic bone morphology.
Main Methods:
- Analysis of linear dimensions of epipubic bones across 61 species.
- Comparative analysis of scaling relationships between taxa with and without marsupia.
Main Results:
- Epipubic bone scaling differs between groups with and without marsupia.
- The scaling does not strongly support the hypothesis of epipubic bones primarily supporting the marsupium.
- Scaling is consistent with a role in locomotion, assisting pelvic limb protraction.
Conclusions:
- Epipubic bone form in marsupials may not be primarily determined by marsupial support.
- Locomotion and maintaining mechanical advantage with trunk muscles are likely key functions.
- Skeletal architecture can scale independently of mass-related stress within certain limits.
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