title: The amniote temporal roof and the diapsid origin of the turtle skull.
abstract: Fossils provide a glimpse into the architecturally complex origins of modern vertebrate body plans. One such origin that has been long debated is that of turtles. Although much attention has been directed toward the origin of the shell, the enigmatic evolution of the turtle skull and its anapsid temporal region has long clouded our understanding of reptile phylogeny. Two taxa, Eunotosaurus africanus and Pappochelys rosinae, were recently and independently described as long-anticipated stem turtles whose diapsid skulls would cement the evolutionary link between turtles and other modern reptile lineages. Detailed μCT analysis of the stratigraphically older and phylogenetically stemward of the two, Eunotosaurus, provides empirical insight into changing developmental trajectories that may have produced the anapsid cranial form of modern turtles and sets the stage for more comprehensive studies of early amniote cranial evolution.
authors.affiliation: Department of Anatomy, New York Institute of Technology, College of Osteopathic Medicine, Old Westbury, NY 11568, USA; Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, P.O. WITS, Johannesburg 20150, South Africa. Electronic address: gbever@nyit.edu.
authors.forename: G S
authors.initials: GS
authors.lastname: Bever
authors.affiliation: Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, P.O. WITS, Johannesburg 20150, South Africa; Department of Earth Sciences, Denver Museum of Nature and Science, 2001 Colorado Boulevard, Denver, CO 80205, USA.
authors.forename: Tyler R
authors.initials: TR
authors.lastname: Lyson
authors.affiliation: Department of Geology & Geophysics and Peabody Museum of Natural History, Yale University, New Haven, CT 06520, USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Field
authors.affiliation: Department of Geology & Geophysics and Peabody Museum of Natural History, Yale University, New Haven, CT 06520, USA.
authors.forename: Bhart-Anjan S
authors.initials: BS
authors.lastname: Bhullar
mesh_terms: D000818:Animals; D005075:Biological Evolution; D005580:Fossils; D012886:Skull / Q000033:anatomy & histology*; D014426:Turtles / Q000033:anatomy & histology* / Q000235:genetics
keywords: Amniote cranial evolution; Anapsid skull; Cranial anatomy; Reptile phylogeny; Testudines