Well, no, but that's what they're claiming they found. What they actually found was that chimps can learn to play games involving trading things they like less for things they like more.
The device was actually just a bowl with a false bottom that held cooked food. The researchers didn't use fire because it could have injured the chimps, and because some chimps might have already seen how humans used it to cook food.So what we haven't learned is how early man came to control fire, or how he learned to cook -- let alone how he learned to build an oven! Fire's too dangerous for the chimps, and no oven construction is being observed.