Posted by: Craig Woolheater on April 12th, 2013
Composite reconstruction of Au. sediba based on recovered material from MH1, MH2 and MH4 and based upon the research presented in the accompanying manuscripts. As all individuals recovered to date are approximately the same size, size correction was not necessary. Femoral length was established by digitally measuring a complete femur of MH1 still encased in rock. For comparison a male common chimpanzee on right. (Credit: Photo by Lee Berger, courtesy of the University of the Witwatersrand)
Australopithecus walked like Sasquatch?
According to a new study, our Australopithecus ancestors may have used different approaches to getting around on two feet. The new findings, co-authored by Boston University researchers Jeremy DeSilva , assistant professor of anthropology, and Kenneth Holt, assistant professor of physical therapy, appear in the latest issue of the journal Science in an article titled “The Lower Limb and Mechanics of Walking in Australopithecus sediba.” The paper is one of six published this week in Science that represent the culmination of more than four years of research into the anatomy of Australopithecus sediba (Au. sediba). The two-million-year-old fossils, discovered in Malapa cave in South Africa in 2008, are some of the most complete early human ancestral remains ever discovered.
The locomotion findings are based on two Malapa Au. sediba skeletons. The relatively complete skeletons of an adult female and juvenile male made possible a detailed locomotor analysis, which was used to form a comprehensive picture of how this early human ancestor walked around its world.
The researchers hypothesize this species walked with a fully extended leg (like humans do), but with an inverted foot (like an ape), producing hyperpronation of the foot and excessive rotation of the knee and hip during bipedal walking. These bipedal mechanics are different from those often reconstructed for other australopiths and suggest that there may have been several forms of bipedalism throughout human evolution.
Australopithecus sediba has a combination of primitive and derived features in the hand, upper limb, thorax, spine, and foot. It also has a relatively small brain, a human-like pelvis, and a mosaic of Homo- and Australopithecus-like craniodental anatomy. The foot in particular possesses an anatomical mosaic not present in either Au. afarensis or Au. africanus, supporting the contention that there were multiple forms of bipedal locomotion in the Plio-Pleistocene. (The recent discovery of an Ardipithecus-like foot from 3.4-million-year-old deposits at Burtele, Ethiopia, further shows that at least two different forms of bipedalism coexisted in the Pliocene.)
Might these findings have an impact on Bigfoot’s bipediality?
The hypothesized style of walking described for Australopithecus sediba sounds very similar to what was shown in Sasquatch: Legend Meets Science.
Jeff Meldrum had this to say regarding this article:
I haven’t seen the original paper in Science yet, but this is a significant specimen adding not only to the taxonomic diversity of early hominins, but to the locomotor diversity as well. The emergence of traits for bipedalism was clearly mosaic in fashion in various hominin lineages. As for A. sediba’s bearing on sasquatch, the combination of traits in the sasquatch foot — non-divegent hallux (big toe), flat flexible midfoot, relatively long digits and heel — are in principle to be found analogously among the diversity of other primate bipeds.Jeff Meldrum