While Olduvai has been picked over before, most notably by the pioneering scientists L. Now, under the organizational umbrella of the Olduvai Geochronology Archaeology Project, an international team of scientists composed of a consortium of researchers and institutions is focusing on reconstructing the picture of the early human transition from the simple "chopper" stone tool technology of the Oldowan industry (see image below), the world's first technology discovered at Olduvai, to the Acheulean, the more sophisticated technology represented most by the well-known bifacial "handaxe" (see image below), some of the first examples of which were found at Saint- Acheul in France, and later at Olduvai.The Oldowan is considered to have been made and used during the Lower Paleolithic, from 2.6 to 1.7 million years ago, whereas the Acheulean emerged about 1.76 million years ago and was used by early humans up to about 300,000 years ago or later."We hypothesized that a soft-tissue mechanism might enable such extreme dorsiflexion," wrote the authors in their study report.They tested their hypothesis by conducting ultrasound imaging of the fibers of the large calf muscles of individuals in all four groups.It demonstrated that a foot and ankle bone structure adapted primarily for walking upright on land does not necessarily exclude climbing as a behaviorally habitual means of mobility for survival.The implications for our possible early human ancestors, such as the species Australopithecus afarensis, are significant.Australopithecus afarensis is an extinct hominid that lived between 3.9 and 2.9 million years ago.
These beds reveal a record of a very important time period (1.79 - 1.15 million years ago), a record that contains evidence of critical changes in the area's fauna, stone tools and climate, such as the disappearance of Homo habilis, a very early hominin and possible human ancestor, and the emergence of Homo erectus, a later hominin considered to be the earliest human ancestor to exit Africa and spread across Eurasia.The findings have implications for some of our earliest possible ancestors, including the 3.5 million-year-old species Australopithecus afarensis, thought by many scientists to be the first known possible human predecessor to have forsaken arboreal life in the trees and live a life walking upright (bipedalism) on the ground.Associate professor of anthropology Nathaniel Dominy of Dartmouth College, along with colleagues Vivek Venkataraman and Thomas Kraft, compared African Twa hunter-gatherers to agriculturalists living nearby, the Bakiga, in Uganda.A chopping tool from Olduvai Gorge, 1 - 2 million years old.GFDL CC-BY-SA, Wikimedia Commons A handaxe from Olduvai Gorge, over 1 million years old."Australopithecus afarensis possessed a rigid ankle and an arched, nongrasping foot," wrote Dominy and his co-authors in the report published in the Proceedings of the National Academy of Sciences (PNAS)."These traits are widely interpreted as being functionally incompatible with climbing and thus definitive markers of terrestriality." But now, the research shows that bone structure alone is not an indisputable indicator that an ancient hominid was exclusively terrestrial.More specifically, they observed that the climbers "walked" up small trees by applying the soles of their feet directly to the trunk and progressing upward, with arms and legs advancing alternately.To do this successfully, they said, required extreme dorsiflexion, or bending the foot upward toward the shin to a degree not normally possible among most modern humans.Researchers involved in a new study led by Oxford University have found that between three million and 3.5 million years ago, the diet of our very early ancestors in central Africa is likely to have consisted mainly of tropical grasses and sedges.The findings are published in the early online edition of Proceedings of the National Academy of Sciences.