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Adaptive Patterns in Aquatic Amniote Bone Microanatomy-More Complex than Previously Thought.
Alexandra Houssaye1, P Martin Sander2, Nicole Klein3
1*Département Ecologie et Gestion de la Biodiversité, UMR 7179 CNRS/Muséum National d'Histoire Naturelle, 57 rue Cuvier CP-55, Paris 75000, France; houssaye@mnhn.fr.
Integrative and Comparative Biology
|October 31, 2016
Summary
Amniotes adapting to aquatic life show diverse bone microanatomy for buoyancy and swimming. This review highlights varied adaptations in extinct and extant species, linking bone structure to lifestyle.
Area of Science:
- Paleontology
- Comparative Anatomy
- Functional Morphology
Background:
- Amniotes exhibit diverse adaptations to aquatic environments, leading to convergent evolution in morphology and physiology.
- Aquatic amniotes display varied traits based on habitat (shallow vs. open marine) and locomotion (surface vs. deep diving).
- Bone microanatomy is crucial for understanding biomechanics and inferring function in extinct species.
Purpose of the Study:
- To review and synthesize knowledge on bone microanatomical adaptations in semi-aquatic and aquatic amniotes.
- To explore the diversity of microanatomical patterns and their functional implications.
- To link skeletal adaptations to habitat, swimming abilities, and evolutionary pressures.
Main Methods:
- Review of existing literature on bone microanatomy in extant and extinct aquatic amniotes.
- Analysis of microanatomical patterns in long bones, vertebrae, and ribs.
- Comparative study across a wide range of (semi-)aquatic species.
Main Results:
- Two main microanatomical specializations exist: bone mass increase and spongious organization, related to buoyancy and swimming.
- A wide spectrum of intermediate patterns between these extremes was observed.
- Significant diversity in microanatomical patterns and their combinations within single skeletons was identified.
Conclusions:
- Bone microanatomy in aquatic amniotes is highly diverse, reflecting varied functional requirements.
- Specific microanatomical features correlate with habitat, swimming mode, and evolutionary adaptations.
- Understanding bone structure provides insights into the functional ecology of extinct aquatic amniotes.
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