Publication Date:
2011-02-12
Description:
The transition to full-time terrestrial bipedality is a hallmark of human evolution. A key correlate of human bipedalism is the development of longitudinal and transverse arches of the foot that provide a rigid propulsive lever and critical shock absorption during striding bipedal gait. Evidence for arches in the earliest well-known Australopithecus species, A. afarensis, has long been debated. A complete fourth metatarsal of A. afarensis was recently discovered at Hadar, Ethiopia. It exhibits torsion of the head relative to the base, a direct correlate of a transverse arch in humans. The orientation of the proximal and distal ends of the bone reflects a longitudinal arch. Further, the deep, flat base and tarsal facets imply that its midfoot had no ape-like midtarsal break. These features show that the A. afarensis foot was functionally like that of modern humans and support the hypothesis that this species was a committed terrestrial biped.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Ward, Carol V -- Kimbel, William H -- Johanson, Donald C -- New York, N.Y. -- Science. 2011 Feb 11;331(6018):750-3. doi: 10.1126/science.1201463.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Pathology and Anatomical Sciences, M263 Medical Sciences Building, University of Missouri, Columbia, MO 65212, USA. wardcv@missouri.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21311018" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Biological Evolution
;
Biomechanical Phenomena
;
Ethiopia
;
Foot/*anatomy & histology/physiology
;
*Fossils
;
Gait
;
Hominidae/*anatomy & histology
;
Humans
;
Locomotion
;
Metatarsal Bones/*anatomy & histology
;
Tarsal Joints/anatomy & histology/physiology
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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