|Title||Complete Fourth Metatarsal and Arches in the Foot of Australopithecus afarensis|
|Publication Type||Journal Article|
|Year of Publication||2011|
|Authors||Ward, CV, Kimbel, WH, Johanson, DC|
|Pagination||750 - 753|
|Keywords||A. afarensis, africa, bipedality, ethiopia, hadar, locomotion, pliocene|
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.
Complete Fourth Metatarsal and Arches in the Foot of Australopithecus afarensis
For years, I've worked on their bones. Now I'm working on their genes. Read more about the science studying these ancient people.
From a finger bone of an ancient human came the record of a completely unexpected population. My lab is working on the science of the Denisova genome.
The advent of agriculture caused natural selection to speed up greatly in humans. We're uncovering some of the ways that populations have rapidly changed during the last 10,000 years.