Chimpanzee hand grips
![chimpanzee hand grips chimpanzee hand grips](http://4.bp.blogspot.com/-GBAA225nXHM/Uye76RTvlTI/AAAAAAAAH2w/WH0JB2QrlUY/s1600/handle+42.jpg)
For example, the production techniques of the earliest stone tools in the hominin lineage (early knapping techniques) for which there is robust data (the Oldowan) have been variously argued to have been socially learned (e.g. Stone tools are available in much larger number, though even then the inferences that are drawn from stone tools remain limited. Bone-based types of data are however extremely rare. Outside of a large number of stone tools from the Early Pleistocene, the only other interpretable evidence is bone tools, bone structures of the hominins themselves, and marks left on bone by tools 2, 3, 4, 5. Neither tool making behavior nor its underlying cognition fossilizes, and so must be inferred from artefacts themselves 1.
#CHIMPANZEE HAND GRIPS FREE#
However, the ability to combine free hand hitting with the force, precision, and accuracy needed to facilitate conchoidal fracture in free hand percussion may still have been a critical watershed for hominin evolution.Ī large body of information on the evolution of human behavior and cognition is inferred from the archeological record.
#CHIMPANZEE HAND GRIPS FOR FREE#
This study helps to shed light on the morphofunctional and cognitive requirements for the emergence of stone tool production as it shows that a prerequisite for free hand percussion (namely, free hand hitting) is part of the spontaneous behavioral repertoire of one of humans’ closest relatives (gorillas). Gorillas are therefore the second non-human lineage primate showing free-hand hitting behavior in the wild, and ours is the first report for free hand hitting behavior in wild apes. We report on five observations of free hand hitting behavior in two wild western gorillas, using stone-like objects (pieces of termite mound). Holding a stone core in hand and hitting it with another in the absence of flaking, free hand hitting, has been considered a requirement for producing sharp stone flakes by hitting stone on stone, free hand percussion. Flaked stone tools have been observed to be accidentally produced when wild monkeys use handheld stones as tools. The earliest stone tool types, sharp flakes knapped from stone cores, are assumed to have played a crucial role in human cognitive evolution.