Chimpanzees given a false "microwave" quickly learned to use it to cook raw food. Further, the chimps preferred cooked food and would carry around raw food (such as potatoes) until they were granted access to the microwave.
For those of you wondering about safety, the "microwave" was actually a box with a false bottom; thus, it "magically" transformed raw food into cooked food, rather than actually using heat to do so. This study shows that chimpanzees intuitively understand that food can be cooked, and indeed prefer cooked food over raw food! Of course, for the behaviour to actually originate in the wild, chimps would have to gain control over fire- and that certainly has not happened.
When did humans first learn to cook? The first direct evidence-- hearths-- come into existence about 250,000 years ago, but some paleoanthropologists argue that our ancestors got cookin' as early as 2.3 million years ago. In Catching FIre: How Cooking Made Us Human, Richard Wrangham argues that the ability to cook increased food efficiency, freeing up energy for brain development and thus advanced cognition in Homo erectus. (The most common alternate hypothesis is that early humans were scavengers, thus increasing food efficiency by avoiding the need to hunt).
Further direct evidence of cooking will help settle this argument, but it is worth concluding with yet another reminder that Neanderthals were far from the brutes they are often depicted to be: pollen grains in Neanderthal teeth demonstrated that Neanderthals cooked and ate vegetables around 36-46 million years ago.
Researchers created a “chimpanzee microwave” and placed it in a wildlife sanctuary. The device isn’t actually a microwave. In fact, it doesn’t cook food at all. Rather, chimps put uncooked food into a bowl with a false bottom, where it was swapped out with cooked food, much like a magic trick. When the chimpanzees realized they could cook food in the “oven,” Hamilton reports, half of them started using it regularly. To determine whether chimpanzees understood the concept of raw and cooked food in the first place, scientists gave chimpanzees cooked and raw foods. Hamilton writes that chimps immediately put raw foods in the device and even held on to raw foods until they could get to the cooking tool.