Hominin stone tool: Accidental or Intentional Innovation

For a long time, the use of tools was considered as one of the basic hominin characteristics. But now it is ascribed to nonhuman primates as well such as chimpanzees, macaques and capuchin monkeys. These primates use the tools to obtain food using twigs to collect ants and insects, and stone tools to break open the nuts to get the edible parts. Our earliest ancestors used flake stone tools to cut animal skin and meat and break the bones for marrow. Making stone tools was considered to be an intentional activity and a necessary step in the human evolutionary process.

But this theory of intentionally making stone tools by our ancestors has been challenged by Lydia Luncz and TomosProffitt of the Max Planck Institute for Evolutionary Biology, Leipzig, Germany.They propose that in the earliest stages of human evolution, tool making could be accidental and not intentional. In support of this idea, they cite the behavior of tool use by long-tailed macaques in the Phang Nga National Park of Thailand. These monkeys have been using stones to crack open the nuts. While doing so, they have been accidentally breaking stones resulting in a large assemblage of broken stones and flake stones. Examination of these broken stones and flakes made accidentally by macaques, and those obtained from the archaeological evidences of hominin tools considered to be madeintentionally by earlier hominins quite often resemble in nature and shapes with each other.

Evolutionary history of man is replete with examples that many new discoveries and inventions were accidental in nature. This point compels us to think that the early man must have accidentally broken the stones into pieces and flakes while crushing the nuts to get the kernel, and the bones of the animals to obtain marrow. Therefore the first discovery of stone tools could be accidental and thereafter when the broken stones and flakes proved useful, the early man may have started making tools intentionally. The further progress of tool making became more and more sophisticated and useful. More research on the tool using behavior of nonhuman primates would unlock this puzzle whether earlier man intentionally made the tools or stumbled upon the accidentally made flakes for being useful for his activities.