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Updated: Jun 25, 2026
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Two-step Approach to Explore Early- and Late-stages of Organ Formation in the Avian Model: The Thymus and Parathyroid Glands Organogenesis Paradigm
Published on: June 17, 2018
The theropod furcula
Sterling J Nesbitt1, Alan H Turner, Michelle Spaulding
1Division of Paleontology, American Museum of Natural History, New York, New York 10024, USA. nesbitt@ldeo.columbia.edu
Journal of Morphology
|February 12, 2009
Summary
The furcula, a fused clavicle unique to theropods, appeared early in their history. Its morphology, though variable in birds, is conserved in non-avian theropods, offering phylogenetic insights.
Area of Science:
- Paleontology
- Evolutionary Biology
- Comparative Anatomy
Background:
- The furcula, formed by fused clavicles, is a key skeletal element in theropod dinosaurs.
- It is considered crucial for understanding the evolutionary link between non-avian theropods and modern birds.
Purpose of the Study:
- To review the development, function, and morphology of the furcula across Theropoda.
- To describe furcular morphology in various non-avian theropods and analyze its phylogenetic significance.
Main Methods:
- Examination of new theropod specimens from the Early Cretaceous of China.
- Detailed analysis of previously collected theropod specimens.
- Review of existing literature on furcular anatomy and terminology.
Main Results:
- The furcula is present in nearly all major theropod clades, indicating its early origin.
- Furcular morphology is highly conserved among non-avian theropods but variable in avian dinosaurs.
- New specimens provide insights into early furcula evolution and phylogenetic character distribution.
Conclusions:
- The furcula likely originated very early in theropod evolution.
- Furcular morphology provides valuable phylogenetic characters for understanding theropod relationships.
- Careful consideration of taphonomic effects is necessary when analyzing furcular morphology.
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