An former human ancestor from South Africa calledAustralopithecus sedibadidn’t have the teeth and jaws to subsist on a steady dieting of gruelling solid food like nuts and seeds . grant to trial on data processor models of a 2 - million - class - old skull key inNature Communicationsthis calendar week , A. sedibacouldn’t generate the high bite personnel take to be a nutcracker like other member of its genus .
Discovered in a cave 40 kilometers ( 25 miles ) Benjamin West of Johannesburg back in 2008,A. sedibais intellection to be a close congenator of our genus , Homo . Unlike other australopiths – who could process intellectual nourishment that were hard to crack open – this species had small grinder and bicuspid , and it also lack large brawniness markings and other feature that would have increased muscle leveraging and facial buttress . Yet , a 2012 analysis of microscopic clothing on the teeth surfaces of two individuals suggested that theA. sedibadiet consisted of hard nutrient mixed with fruits , leave , and bark . The dietary grounds seems to go against interpretations of their useable general anatomy .
University of New England’sJustin Ledogarand fellow wanted to see if the facial skeleton ofA. sedibais well configured ( or even adapted ) to consume hard intellectual nourishment . The squad created a 3D virtual reconstruction of the cranium of a keyA. sedibaspecimen know as MH1 , and then they subjected the computer model to a series of biomechanical tests to study the chewing mechanics .
The team discover thatA. sedibadidn’t have the jaw and tooth structure require to exist on severe foods . So while they might have deplete crackpot and cum , this limitation on their power to bite powerfully think of that they likely were n’t accommodate to consume such grueling foods . " If it had burn as firmly as possible on its molar tooth using the full force of its chewing muscles , it would have dislocated its jaw , " Ledogar says in astatement . The foods important for their selection must have been eaten relatively easy without high forces .
These finding could avail us better understand the environmental changes that play a role in the descent of our own genus . " Humans also have this limitation on biting forcefully and we suspect that earlyHomohad it as well , yet the other australopiths that we have examined are not nearly as determine in this regard,“Ledogar adds . " This means that whereas some australopith population were evolving adaptations to maximise their ability to bite powerfully , others ( includingA. sediba ) were evolve in the opposite focus . "
