title: The foot and ankle of Australopithecus sediba.
abstract: A well-preserved and articulated partial foot and ankle of Australopithecus sediba, including an associated complete adult distal tibia, talus, and calcaneus, have been discovered at the Malapa site, South Africa, and reported in direct association with the female paratype Malapa Hominin 2. These fossils reveal a mosaic of primitive and derived features that are distinct from those seen in other hominins. The ankle (talocrural) joint is mostly humanlike in form and inferred function, and there is some evidence for a humanlike arch and Achilles tendon. However, Au. sediba is apelike in possessing a more gracile calcaneal body and a more robust medial malleolus than expected. These observations suggest, if present models of foot function are correct, that Au. sediba may have practiced a unique form of bipedalism and some degree of arboreality. Given the combination of features in the Au. sediba foot, as well as comparisons between Au. sediba and older hominins, homoplasy is implied in the acquisition of bipedal adaptations in the hominin foot.
authors: Institute for Human Evolution, University of the Witwatersrand, Post Office Wits, 2050 Wits, South Africa. bernhard.zipfel@wits.ac.za
authors: Bernhard
authors: B
authors: Zipfel
authors: Jeremy M
authors: JM
authors: DeSilva
authors: Robert S
authors: RS
authors: Kidd
authors: Kristian J
authors: KJ
authors: Carlson
authors: Steven E
authors: SE
authors: Churchill
authors: Lee R
authors: LR
authors: Berger
mesh_terms: D000818:Animals; D000842:Ankle / Q000033:anatomy & histology* / Q000502:physiology; D000843:Ankle Joint / Q000033:anatomy & histology / Q000502:physiology; D005075:Biological Evolution; D001696:Biomechanical Phenomena; D002111:Calcaneus / Q000033:anatomy & histology; D005260:Female; D005528:Foot / Q000033:anatomy & histology* / Q000502:physiology; D005529:Foot Bones / Q000033:anatomy & histology*; D033023:Foot Joints / Q000033:anatomy & histology / Q000502:physiology; D005580:Fossils; D015186:Hominidae / Q000033:anatomy & histology* / Q000502:physiology; D006801:Humans; D008124:Locomotion; D008297:Male; D008682:Metatarsal Bones / Q000033:anatomy & histology; D013019:South Africa; D013628:Talus / Q000033:anatomy & histology; D013639:Tarsal Bones / Q000033:anatomy & histology*; D013977:Tibia / Q000033:anatomy & histology