title: Distinct growth of the nasomaxillary complex in Au. sediba.
abstract: Studies of facial ontogeny in immature hominins have contributed significantly to understanding the evolution of human growth and development. The recently discovered hominin species Autralopithecus sediba is represented by a well-preserved and nearly complete facial skeleton of a juvenile (MH1) which shows a derived facial anatomy. We examined MH1 using high radiation synchrotron to interpret features of the oronasal complex pertinent to facial growth. We also analyzed bone surface microanatomy to identify and map fields of bone deposition and bone resorption, which affect the development of the facial skeleton. The oronasal anatomy (premaxilla-palate-vomer architecture) is similar to other Australopithecus species. However surface growth remodeling of the midface (nasomaxillary complex) differs markedly from Australopithecus, Paranthropus, early Homo and from KNM-WT 15000 (H. erectus/ergaster) showing a distinct distribution of vertically disposed alternating depository and resorptive fields in relation to anterior dental roots and the subnasal region. The ontogeny of the MH1 midface superficially resembles some H. sapiens in the distribution of remodeling fields. The facial growth of MH1 appears unique among early hominins representing an evolutionary modification in facial ontogeny at 1.9 my, or to changes in masticatory system loading associated with diet.
authors.affiliation: Dept. Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY 10010, USA.
authors.forename: Rodrigo S
authors.initials: RS
authors.lastname: Lacruz
authors.affiliation: Dept. Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY 10010, USA.|Depts. of Biomaterials &Biomimetics, New York University College of Dentistry, New York, NY 10010 USA.
authors.forename: Timothy G
authors.initials: TG
authors.lastname: Bromage
authors.affiliation: Centre for Anatomical and Human Sciences, Hull York Medical School, University of York, York, YO10 5DD, UK.
authors.forename: Paul
authors.initials: P
authors.lastname: O'Higgins
authors.affiliation: Centre for Anatomical and Human Sciences, Hull York Medical School, University of York, York, YO10 5DD, UK.|Facultad de Ondontología and Facultad de Medicina, Universidad de Chile.
authors.forename: Viviana
authors.initials: V
authors.lastname: Toro-Ibacache
authors.affiliation: Dept. Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY 10010, USA.
authors.forename: Johanna
authors.initials: J
authors.lastname: Warshaw
authors.affiliation: Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3,Wits 2050, South Africa.
authors.forename: Lee R
authors.initials: LR
authors.lastname: Berger
mesh_terms: D000818:Animals; D005075:Biological Evolution; D005145:Face / Q000502:physiology*; D020342:Finite Element Analysis; D005580:Fossils; D015186:Hominidae / Q000033:anatomy & histology* / Q000254:growth & development; D006801:Humans; D008445:Maxillofacial Development / Q000502:physiology; D008855:Microscopy, Electron, Scanning; D009295:Nasal Bone / Q000033:anatomy & histology; D012886:Skull / Q000033:anatomy & histology*; D014057:Tomography, X-Ray Computed