TY - JOUR
T1 - Osteological description of an embryonic skeleton of the extinct elephant bird, aepyornis (palaeognathae
T2 - Ratitae)
AU - Balanoff, Amy M.
AU - Rowe, Timothy
N1 - Funding Information:
We are indebted to Ms. Nancy Beers of National Geographic Society’s Explorer’s Hall for loan of the specimen. Thanks to Chris Bell, Gabe Bever, and Matt Colbert for reading drafts of the manuscript and providing many useful comments. Julia Clarke and an anonymous reviewer also provided insightful commentary. We thank Bob Rainey for his patience and assistance in the reconstruction of the embryonic skull. Wann Langston, Ernie Lundelius, and Ron Tykoski also assisted in the reconstruction process. Also thanks to Matt Colbert, Jessie Maisano, John Mai-sano, Julian Humphries, and Rich Ketcham for help in many different technical capacities. We thank the National Science Foundation (grants IIS-0208675, and AToL 0531767) and the Geology Foundation of the Jackson School of Geosciences, The University of Texas at Austin, for helping to fund this project.
PY - 2007/12
Y1 - 2007/12
N2 - The embryonic skeleton of the most massive bird ever discovered, the extinct elephant bird Aepyornis, has remained until this time essentially unknown. This state is due, in large part, to the reluctance to open complete, unbroken eggs. However, the advent of high-resolution X-ray computed tomography (HRCT) provides a non-destructive means of looking inside such eggs to observe the contents that they conceal. This study uses HRCT technology to digitally extract an embryonic skeleton from a complete Aepyornis egg and subsequently to aid in the systematic description of this specimen. Skeletal elements digitally retrieved from the egg include portions of the braincase, palate, rostrum, vertebral column, and both the fore- and hindlimbs. Because this specimen is at a relatively early stage of ontogenetic development, the bones that were recovered reveal morphology that typically is obliterated in the adult due to the highly fused state of the skeleton, especially seen in the skull. The usefulness of this information, however, is limited unless a level of ontogenetic maturity can be assigned to the specimen. Therefore, we use an extant phylogenetic bracket in a novel analysis comparing the morphological developmental of living ratites and chickens with this specimen of Aepyornis to assess its level of ontogenetic maturity.
AB - The embryonic skeleton of the most massive bird ever discovered, the extinct elephant bird Aepyornis, has remained until this time essentially unknown. This state is due, in large part, to the reluctance to open complete, unbroken eggs. However, the advent of high-resolution X-ray computed tomography (HRCT) provides a non-destructive means of looking inside such eggs to observe the contents that they conceal. This study uses HRCT technology to digitally extract an embryonic skeleton from a complete Aepyornis egg and subsequently to aid in the systematic description of this specimen. Skeletal elements digitally retrieved from the egg include portions of the braincase, palate, rostrum, vertebral column, and both the fore- and hindlimbs. Because this specimen is at a relatively early stage of ontogenetic development, the bones that were recovered reveal morphology that typically is obliterated in the adult due to the highly fused state of the skeleton, especially seen in the skull. The usefulness of this information, however, is limited unless a level of ontogenetic maturity can be assigned to the specimen. Therefore, we use an extant phylogenetic bracket in a novel analysis comparing the morphological developmental of living ratites and chickens with this specimen of Aepyornis to assess its level of ontogenetic maturity.
UR - http://www.scopus.com/inward/record.url?scp=38049010411&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=38049010411&partnerID=8YFLogxK
U2 - 10.1671/0272-4634(2007)27[1:ODOAES]2.0.CO;2
DO - 10.1671/0272-4634(2007)27[1:ODOAES]2.0.CO;2
M3 - Article
AN - SCOPUS:38049010411
SN - 0272-4634
VL - 27
SP - 1
EP - 53
JO - Journal of Vertebrate Paleontology
JF - Journal of Vertebrate Paleontology
ER -