Cooking is astonishingly important. It’s amazing how much caloric energy we use up chewing and digesting raw food. In fact, people on a diet of raw food generally don’t get sufficient calories unless they first “pre-chew” the food in a blender. Women who choose to eat only raw food typically cease menstruating. (You learn something new every day.) You might think that eccentric foodies who eat only raw food and begin slowly to die need meat to survive. But no, not at all. You can live quite well on nuts, tubers, fruits and veggies if you cook them first.

Some years ago – in 2009, to be precise — Richard Wrangham gave us Catching Fire: How Cooking Made Us Human. The author, a professor of biological anthropology at Harvard University, proposed that cooking was the breakthrough that allowed us humans to grow big brains. Cooking does a number of things to food, depending on what food it is, but once it gets past your taste buds the important thing is that cooking increases the number of calories available to the digestive system. Furthermore, cooking reduces our need to pre-digest the food by continuous chewing. Our evolutionary relatives, the gorillas, have to chew all day to absorb enough nutrition to keep them going. Now, who knew that? Cooking, therefore, makes more energy available to the human body and that surplus energy can be used for the development of a bigger brain compared to the size of the digestive system.

Wrangham believes that cooking not only provided humans with the energy to develop bigger brains, it also brought about the sexual division of labor and its subsequent cultural effects. Male and female primates gather the same kinds of food, but when humans began to cook food they had easier access to more calories and as a consequence, males could range farther and focus on hunting; meanwhile, gathering food and cooking it was relegated to women. In Wrangham’s view, the pairing and mating of humans is based not on sex but on cooking. Yes, Well. A lot of us who are not biological anthropologists think that human pairing and bonding is based on sex until the pair gets to middle age or considerably later — after that, maybe, cooking takes over.

Wrangham is quite persuasive. As he points out, the largest transformation in hominids happened around two million years ago. Prior to that change, our early ancestors were smaller, had comparatively smaller brains, large faces and jaws, larger molars for grinding, a much longer and larger digestive system, more flexible feet and longer forearms that would be useful for swinging yourself around if you preferred to live in trees. We looked more like apes than we do now. Furthermore, the improved version of our distant parents — the updated edition with larger brains, smaller teeth and less massive jaws, and a smaller digestive system — that version, called homo erectus, spread farther around the globe and was clearly more adaptable to different environments. Bigger brains made a big difference. Cooking our food provided the surplus energy for our bigger, energy-hungry brains. This is all very, very persuasive.

Wrangham places the first glorious gastronomical event of a cooked meal about 1,800,000 years ago. Unfortunately, most other scholars say there’s no evidence that humans used fire until about a million years later. Estimates vary so widely as to make you shrug and give up. Maybe cooking began as far back as 1,500,000 years ago, but perhaps only 230,00 years ago, depending on what evidence you accept. There’s plenty good evidence that Neanderthals, who inhabited the planet starting from about 400,000 all the way to 40,000 years ago, were able to control fire when they found it after a lightening strike from a summer storm. But there’s no evidence they had fires during the winter, and if you could make fire you’d certainly make it during a Neanderthal winter. On the other hand, fans of Neanderthals, and there are some within scholarly ranks, believe there is indeed evidence that they did. Well, something happened a long time ago to decrease our guts and increase our brains. And maybe it was cooked food. Your brain uses about 13 watts or 260 kilocalories per day, a fifth of the body’s resting power. You can get hungry simply by trying to figure out when people learned to make fire and cook food.