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Updated: Jun 10, 2026
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Assessing Species-specific Contributions To Craniofacial Development Using Quail-duck Chimeras
Published on: May 31, 2014
All About That Base: Dietary Plasticity, Basicranial Flexion and Sphenoid Form.
Elizabeth Jewlal1, Susan E Lad2, Matthew J Ravosa1,3
1Center for Functional Anatomy and Evolution, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
American Journal of Biological Anthropology
|June 9, 2026
Summary
Facial length does not impact basicranial flexion postnatally. However, diet-related plasticity affects sphenoid joints and pterygoid plates due to feeding and loading, influencing mammalian craniofacial development.
Area of Science:
- Evolutionary biology
- Developmental biology
- Paleontology
Background:
- The mammalian sphenoid bone is crucial for skull structure, linking the cranial vault and face.
- Its complex morphology and development are influenced by evolutionary and developmental factors.
- Understanding sphenoid development is key to studying mammalian skull form and function.
Purpose of the Study:
- Investigate factors influencing postnatal sphenoid development, particularly beyond brain growth.
- Examine the roles of facial length, cyclical loading, and feeding modality on basicranial flexion and sphenoid robusticity.
- Address gaps in knowledge regarding the adaptive significance of sphenoid phenotypic diversity.
Main Methods:
- Utilized microcomputed tomography (microCT) data from a rabbit model exhibiting dietary plasticity.
- Analyzed the relationship between postnatal facial length and basicranial flexion.
- Assessed osteogenesis in pterygoid plates and sphenoid joints in response to feeding modality and cyclical loading.
Main Results:
- Postnatal facial elongation did not correlate with decreased basicranial flexion, suggesting prenatal origins for flexion.
- Sphenoid joints and pterygoid plates demonstrated diet-related plasticity.
- Adaptive changes were observed in response to cyclical loading and feeding modality, varying by bone site.
Conclusions:
- Cyclical loading and feeding modality are critical drivers of postnatal craniofacial development in mammals.
- These factors must be considered when studying the structure and function of mammalian skulls, both living and extinct.
- Basicranial flexion is largely established during prenatal development, independent of postnatal facial growth.
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