Pure Pedantry : Chimps have been cracking nuts for a long time

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Jake Young is a MD/PhD student at Mount Sinai School of Medicine focusing in Neuroscience. He is due to graduate in 2032. He received a BS and a MS in Biological Sciences from Stanford University -- where he spent most of his time drinking heavily and building vegetable catapults instead of learning information that would now be eminently useful. When he is not failing terrifically to perform his sworn duties, he enjoys watching bad movies, ethnic food, and running.

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Chimps have been cracking nuts for a long time

Category: Aminals • Evolution
Posted on: February 16, 2007 9:38 AM, by Jake Young

I know that a bunch of other people covered this story, but I managed to find a video of it so I thought I would post it anyway.

Researchers working in Ivory Coast have found remnants of a chimpanzee habitation from over 4,000 years ago, and these remnants include tools that chimps use to break open nuts:

Researchers have found evidence that chimpanzees from West Africa were cracking nuts with stone tools before the advent of agriculture, thousands of years ago. The result suggests chimpanzees developed this behaviour on their own, or even that stone tool use was a trait inherited from our common ancestor. Julio Mercader, Christophe Boesch and colleagues found the stones at the Noulo site in Cote d'Ivoire, the only known prehistoric chimpanzee settlement. The stones they excavated show the hallmarks of use as tools for smashing nuts when compared to ancient human or modern chimpanzee stone tools. Also, they found several types of starch grains on the stones; part of the residue derived from cracking local nuts. The tools are 4300 years old, which, in human terms, corresponds to the Later Stone Age (PNAS, February 2007).

Before this study, chimpanzees were first observed using stone tools in the 19th century. Now, thanks to this new archaeological find, tool use by chimpanzees has been pushed back thousands of years. The authors suggest this type of tool use could have originated with our common ancestor, instead of arising independently among hominins and chimpanzees or through imitation of humans by chimpanzees.
This study confirmed that chimpanzees and human ancestors share for thousands of years several cultural attributes once thought exclusive of humanity, including transport of raw materials across the landscape; selection and curation of raw materials for a specific type of work and projected usage; habitual reoccupation of sites where garbage and debris accumulate; and the use of locally available resources. Nut cracking behaviour in chimpanzees is transmitted socially, and the new discoveries presented in this study shows that such behaviour has been transmitted over the course of many chimpanzee generations.

The article is published in the February issue of PNAS (although I can't manage to find the abstract at the moment).

They have some cool videos of this behavior on their site, one of which is below: