Chimps would cook - if they had the tools

Chimps in the kitchen might sound like a Pixar movie plot, but researchers have figured out that the primates could do if it wasn't for one big problem. Our nearest evolutionary cousins, chimpanzees have already been shown to have ambitious problem-solving skills, not to mention more comedic talents in line with our own, but a new study explored one of the biggest gulfs between us and them: our progression to cooking food rather than eating it raw.

It's an important transition in evolutionary terms. Some scientists believe that getting to grips with using fire to cook meat and vegetables – and thus gain extra nutritional value from them, among other things – was instrumental in propelling the early predecessors to modern humans to their next stage of development.

The question, therefore, was whether chimps had the same capacity, though testing it required more than just putting one in a chef's hat and apron.

Instead, Harvard psychologists Felix Warneken and Alexandra Rosati pieced together a total of nine different trials for the animals to go through. Each was intended to demonstrate whether or not the chimps had the cognitive chops to recognize the value of food: understanding the process of going from raw to cooked, for instance.

Turns out, the hairy sous chefs were surprisingly quick learners. Warneken and Rosati showed that not only did the chimps – from Tchimpounga Chimpanzee Sanctuary in the Republic of Congo – prefer cooked food to raw, but they could grasp the idea of cooking: the psychologists replicated it in concept, putting raw sweet potato or carrots into a box and then, with some sleight of hand, switching them for the cooked equivalent.

Impressively, the chimps also demonstrated willingness to wait for their food to be cooked, not to mention overcoming the urge to eat whatever they had and instead put it into the faux-cooker. The animals would even save raw food with the expectation that there'd be an opportunity to make the preferred cooked version later on.

"Together, our results indicate that several of the fundamental psychological abilities necessary to engage in cooking may have been shared with the last common ancestor of apes and humans, predating the control of fire," Warneken and Rosati conclude.

The big omission in the chimps' culinary toolbox, of course, is fire. Without any ability to create it for themselves, the method of cooking is out of reach, even if the ambition and understanding of concept is there.

Still, it's not quite as clean-cut, perhaps. Chimpanzees will go hunting for roasted seeds in the aftermath of forest fires, the researchers point out, raising questions about opportunistic versus exploitative use of cooking possibilities.

"Some opportunistic use of natural fires – underpinned by the types of cognitive capacities examined in the current studies – may have played an important role in bootstrapping the emergence of more complex cooking behaviors that required the active control and maintenance of fire," the pair suggest.

SOURCE Proceedings of the Royal Academy B