Science Questions

Are we the only animals to cook our food?

Are we the only animals to cook food, why do we do it and does it give us an advantage over other animals? Kathleen, Oregon

We put this to:

Robert Foley, Professor of Human Evolution at the Leverhulme Centre for Human Evolutionary Studies, Cambridge.

Cooking is certainly unique to humans. There’s no other species that does it. There’s obvious reasons for that because we’re the only ones that can make fire which is a pre-requisite. In a away fire comes first and cooking becomes a process after it. It’s becoming clear that really cooking provides quite a number of advantages. Richard Wrangham from Harvard has been doing a lot of experiments looking at how cooking can change the nutritional value of food. What it seems is that the process of warming food up: in a sense denaturing it has a number of effects. One is that food is much more tender. That we know. If you eat a cooked carrot instead of a raw carrot it’s much easier. We can spend less time chewing, we can swallow it faster and we can digest it faster. It seems that it’s an extension of things we see in other animals. Animals who use techniques often in their stomachs to tenderise food seem to try and make it more easily absorbable. If we turn to the other question of when all this happened the real question is when do we first find evidence of fire? That seems to be about half a million years ago or so. We don’t find direct evidence of cooking then but we do see over the next 100,000 years or so the beginnings of things like burnt stone which suggests that meat is cooked. It’s probably goes quite a long way back in our evolutionary history and some people would argue it’s really a very major change in the way we are able to live and survive.

Peter Lucas, Professor of Anthropology, George Washington University, USA

The second possible advantage for cooking is that it improves digestion. We’ve done a model study here particularly with Zhongquan Sui when she was here – she’s now at the University of Perdue. She found that yes, cooking does to a certain extent improve digestion. You only need cook something for a fraction of the time that you actually do in order for it to be digested properly. The cooking times that people adopt when they normally say this is cooked seem to reflect strong mechanical changes in the food. In other words, these are things that affect you perception of food texture and allow you actually to eat it very much easier, very much shorter eating times than you would do if they’re raw. That I think I would give as the essential answer at the moment.

November 2008