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The theropod furcula
Sterling J. Nesbitt,
Alan H. Turner,
Michelle Spaulding,
Jack L. Conrad,
Mark A. Norell,
Corresponding Author
Sterling J. Nesbitt
Division of Paleontology, American Museum of Natural History, New York, New York 10024
Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964
Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024Search for more papers by this authorAlan H. Turner
Division of Paleontology, American Museum of Natural History, New York, New York 10024
Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964
Search for more papers by this authorMichelle Spaulding
Division of Paleontology, American Museum of Natural History, New York, New York 10024
Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964
Search for more papers by this authorJack L. Conrad
Division of Paleontology, American Museum of Natural History, New York, New York 10024
Search for more papers by this authorMark A. Norell
Division of Paleontology, American Museum of Natural History, New York, New York 10024
Search for more papers by this authorSterling J. Nesbitt,
Alan H. Turner,
Michelle Spaulding,
Jack L. Conrad,
Mark A. Norell,
Corresponding Author
Sterling J. Nesbitt
Division of Paleontology, American Museum of Natural History, New York, New York 10024
Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964
Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024Search for more papers by this authorAlan H. Turner
Division of Paleontology, American Museum of Natural History, New York, New York 10024
Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964
Search for more papers by this authorMichelle Spaulding
Division of Paleontology, American Museum of Natural History, New York, New York 10024
Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964
Search for more papers by this authorJack L. Conrad
Division of Paleontology, American Museum of Natural History, New York, New York 10024
Search for more papers by this authorMark A. Norell
Division of Paleontology, American Museum of Natural History, New York, New York 10024
Search for more papers by this authorAbstract
The furcula is a structure formed by the midline fusion of the clavicles. This is the element which is unique to theropods and is important for understanding the link between birds and other theropods. New specimens from basal theropods suggest that the furcula appeared very early in theropod history. We review furcula development, function, and morphology, as well as the anatomical terminology applied to it. Furcular morphology is highly variable in crown-group avians but is rather conserved among nonavian theropods. Here we review, or describe for the first time, the furculae in many nonavian theropods. Furculae occur in nearly all major clades of theropods, as shown by new theropod specimens from the Early Cretaceous of China and a close inspection of previously collected specimens. Informative phylogenetic characters pertaining to the furcula occur throughout Theropoda, though care should betake to consider taphonomic effects when describing furcular morphology. J. Morphol., 2009. © 2009 Wiley-Liss, Inc.
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