title: Mosaic morphology in the thorax of Australopithecus sediba.
abstract: The shape of the thorax of early hominins has been a point of contention for more than 30 years. Owing to the generally fragmentary nature of fossil hominin ribs, few specimens have been recovered that have rib remains complete enough to allow accurate reassembly of thoracic shape, thus leaving open the question of when the cylindrical-shaped chest of humans and their immediate ancestors evolved. The ribs of Australopithecus sediba exhibit a mediolaterally narrow, ape-like upper thoracic shape, which is unlike the broad upper thorax of Homo that has been related to the locomotor pattern of endurance walking and running. The lower thorax, however, appears less laterally flared than that of apes and more closely approximates the morphology found in humans.
authors.affiliation: Anthropological Institute and Museum, University of Zurich, Zurich, Switzerland. smidi@aim.uzh.ch
authors.forename: Peter
authors.initials: P
authors.lastname: Schmid
authors.forename: Steven E
authors.initials: SE
authors.lastname: Churchill
authors.forename: Shahed
authors.initials: S
authors.lastname: Nalla
authors.forename: Eveline
authors.initials: E
authors.lastname: Weissen
authors.forename: Kristian J
authors.initials: KJ
authors.lastname: Carlson
authors.forename: Darryl J
authors.initials: DJ
authors.lastname: de Ruiter
authors.forename: Lee R
authors.initials: LR
authors.lastname: Berger
mesh_terms: D000818:Animals; D005075:Biological Evolution; D005260:Female; D005580:Fossils; D015186:Hominidae / Q000033:anatomy & histology* / Q000502:physiology*; D006801:Humans; D008124:Locomotion; D008297:Male; D012119:Respiration; D012272:Ribs / Q000033:anatomy & histology*; D013019:South Africa; D013909:Thorax / Q000033:anatomy & histology*