Stone butchery before Homo appeared? (Introduction)

by David Turell , Tuesday, August 18, 2015, 17:01 (3384 days ago)

Marks from 3.4 million years ago are suggestive:-http://www.sciencedaily.com/releases/2015/08/150813171207.htm-"Marks on two 3.4 million-year-old animal bones found at the site of Dikika, Ethiopia, were not caused by trampling, an extensive statistical analysis confirms. The results of the study developed new methods of fieldwork and analysis for researchers exploring the origins of tool making and meat eating in our ancestors. -***-"The 12 marks on the two specimens -- a long bone from a creature the size of a medium antelope and a rib bone from an animal closer in size to a buffalo -- most closely resemble a combination of purposeful cutting and percussion marks, Thompson says. "When these bones were hit, they were hit with enormous force and multiple times."-The paper supports the original interpretation that the damage to the two bones is characteristic of stone tool butchery, published in Nature in 2010. That finding was sensational, since it potentially pushed back evidence for the use of stone tools, as well as the butchering of large animals, by about 800,000 years.-***-"'We would really like to understand what caused these marks," Thompson says. "One of the most important questions in human evolution is when did we start eating meat, since meat is considered a likely explanation for how we fed the evolution of our big brains."-"Evidence shows that our genus, Homo, emerged around 2.8 million years ago. Until recently, the earliest known stone tools were 2.6 million years old. Changes had already been occurring in the organization of the brains of the human lineage, but after this time there was also an increase in overall brain size. This increased size has largely been attributed to a higher quality diet.-"While some other apes are known to occasionally hunt and eat animals smaller than themselves, they do not hunt or eat larger animals that store abundant deposits of fat in the marrow of their long bones. A leading hypothesis in paleoanthropology is that a diet rich in animal protein combined with marrow fat provided the energy needed to fuel the larger human brain.-"The animal bones in the Dikika site, however, have been reliably dated to long before Homo emerged. They are from the same sediments and only slightly older than the 3.3-million-year-old fossils unearthed from Dikika belonging to the hominid species Australopithecus afarensis."