London, Aug 21: Hominins developed a strong grip comparable to modern human hands at least 500,000 years ago, revealing a study of ancient stone tools.
The findings showed that without the ability to perform very powerful precision handling, our ancestors would not have been able to produce advanced types of stone tools such as spearheads.
The technique involves preparing a conspicuous area on a tool to remove specific stone flakes and form the tool into a pre-designed design.
This research is the first to link a stone tool production technique known as "platform preparation" to the biology of human hands, according to researchers at the Britian's University of Kent.
Platform preparation is essential for making many different types of advanced prehistoric stone tools, the earliest known event of which was observed at the 500,000 year old site of Boxgrove in West Sussex (UK).
"Handbones from before 300,000 years ago are rare, especially compared to other human fossils such as teeth, so the fact that we can study the manipulation skills of our early ancestors of the stone tools they produced is incredibly exciting," said lead author Alastair Key of the varsity.
For the study, described in the journal PeerJ, the team investigated how hands are used in the production of different types of early stone technology.
Using sensors that were confirmed by experienced flint knives (producers of stone implements), the researchers were able to establish that platform preparation behavior forced the hand to exert considerably more pressure through the fingers compared to all the other stone tools studied.
The study shows that the Boxgrove hominins (early people) required significantly stronger grades compared to previous populations that did not perform this behavior.
It further suggests that highly modified and shaped stone tools, such as the handles, discovered at Boxgrove and stone spearheads found in later prehistoric times, could not be produced until humans developed the ability to perform particularly powerful grips, the researchers said.