A new psychoanalysis of 3.4 - million - class - old beast bones suggests that our early ancestors may have been butchering animate being with stone tools 800,000 years earlier than we thought . The findings were published in theJournal of Human Evolutionlast week .
Several years ago , two osseous tissue were observe in the Hadar Formation at Dikika in Ethiopia . One is a long bone from an animal about the size of it of a average antelope ; the other is a rib from a buffalo - sized beast . And they were cover with a dozen gull . A 2010 bailiwick interpreted the marker as legal injury from endocarp prick butchery , but accord to a 2011 paper , the home run were triggered by incidental trampling by various animals over the course of millennia .
“ We would really care to realise what caused these marks,”Emory University ’s Jessica Thompsonsays in astatement . “ One of the most important questions in human organic evolution is when did we start eat meat , since meat is considered a potential account for how we fed the organic evolution of our great brains . ”Until latterly , the onetime stone cock were dated to 2.6 million years , andHomo habilisthe “ handy man ” was thought to be the first toolmaker . But study published this year suggest that our out ascendant ( and probably from a different genus than ours ) weremaking stone tools some 3 million years ago .
To investigate the controversial span further , Thompson and confrere studied the shapes and sizes of more than 450 marks found on 4,000 other bones pick up from Dikika and nearby deposits . They then compared these to trampling marks through an experiment created on modern - 24-hour interval bones , as well as to the marks on the two bone in interrogation .
The marks on the heatedly debated two , the squad reason out , most closely resemble a combination of purposeful newspaper clipping and pleximetry marks – and are n’t characteristic of trampling . “ When these bones were attain , they were hit with enormous force and multiple times,”Thompson explains . “ The best catch we have for the marks , using currently available information , would still be shambles with stone tools . ”
When the team test Amandine Aurore Lucie Dupin grains from the fossil site , they found that these were polish – andnot the angular type , which would have produce striations on a trample pearl . Trample mark tend to be shallow and curvy ; cuts made by peter are typically true and create a narrow-minded , V - shaped groove . While the legal injury found on many of the other bones at the land site seems to have been bring down by trampling , it seems that these two bones are outlier .
