Catching Fire: How Cooking Made Us Human Paperback – September 7, 2010

I've always loved creation myths. How we came to be is a question all cultures ask. The Iroquois believed we were created by the Sky People. The Australian Aborigines by the Sun Mother, the African Bushmen believed people emerged from the depths of the earth, and the Hebrew Bible believes in a god that constructed the universe in seven days and started humans with Adam and Eve.But it was only the invention of science, which is basically a method of testing reality, that has finally allowed us to understand our true origins. The disciplines of evolution, genetics, and archeology have allowed us to trace our ancestry back millions of years.Wrangham's book "Catching Fire" makes the case that we couldn't have evolved our large brains without fire.Fire played a role in our evolution in many ways. We could have never become the "Naked Ape" without fire, or we would have died of cold at night. Losing our hair opened a new niche - we became the best creature on earth at running long distances, and could do it in mid-day heat when furry creatures would have died from overheating (1).Fire kept dangerous animals at bay, gave us safe food and water by killing bacteria, dried our clothes, signaled friends, made otherwise indigestible or poisonous food edible, and reduced spoilage. Cooked food tastes much better than raw food -just ask Koko the gorilla, who signed that that was why she liked it. Children can be weaned earlier and grow faster. All of the above led to longer lives, which greatly shaped human societies.When you ask people what's essential to survival, they'll usually say food, water, and shelter. But by the end of this book, I'm sure they'll add fire to the list. We still depend on the "fire" in the fossil fuels powering electric lines, combustion engines, gas stoves, and so on.Of all the ways fire has helped us, the most important may be due to cooked food having more usable calories than raw food, and cooked food can be consumed much faster. So instead of spending more than six hours a day chewing fruit and leaves like our chimpanzee relatives do, we spend about an hour a day chewing.The higher number of calories from cooked food versus raw was surprisingly only discovered recently when tests were done on people who've had their large intestines removed. Food was taken out after the small intestine, which is where most of our ability to get nutrition takes place. After that, the bacteria in our large intestine steals most of the remaining food for themselves.For example, your body can digest 94% of the protein in cooked eggs, but only 65% raw. This is because heat increases the digestibility of protein. Besides heat, proteins are more digestible if denatured in acids like lemon juice - think of ceviche, pickling, marinades, salt, or drying.If you're a food geek, you'll love all the details Wrangham gives about what cooking does to food, why we get more calories from cooked than raw food, or the minutiae of your digestive system. Perhaps you'll even become a better cook learning how heat breaks down starches and protein, at what temperatures meat is most tender, food safety, and so on.Wrangham makes the case we're adapted and dependent on cooked food in the first few chapters showing how we've lost the ability to survive on raw food alone. Although more studies need to be done, the current scientific consensus is that a strict diet of raw food does not provide an adequate energy supply. Dieters take note! Yes, there are raw food consumers who are alive and well, so you'll need to read the details to find out why their food is quite different from what our ancestors would have found in the wild.Rumors that tribal people like the Inuit ate their food raw turned out not to be true. Certainly some food is eaten raw, especially the softer organs like liver or stomach, but most of the calories the Inuit eat are cooked. Women use twigs in summer, and seal oil or blubber to boil meat in the winter.All species of mammals digest cooked food easier. Farmers like to give cooked swill to their animals because they gain weight much faster. And that's why your pets get so fat, all pet food is cooked.Our anatomy shows that we've adapted to cooked food. We have weak jaws, and really small mouths and lips compared to our closest relatives, the chimpanzees, who need big mouths, lips, and strong jaws to digest leaves and fruit.We use 20% of our energy to fuel our brains, which are only 2.5% of our body weight. The average primate uses 13% and mammals 8 to 10% of their energy to fuel their brains.That energy came from smaller guts, because with cooked food we didn't need to have a large digestive system. Birds also evolved a small gut system, but they put their extra energy into wing muscles. We used the extra energy for brain power, because social intelligence helped people survive longer.The shorter gut, bigger brain theory is far from proven, and since this book was published many examples of where this not being true have been proposed, so stay tuned to whether this ends up being completely, or partially true as an explanation of how we evolved.The average human diet is two-thirds starchy food. The finer the flour, the more it's digested, and modern white flour is basically a starchy powder, which is why so many Americans are overweight. Worse yet, these calories are empty since wheat and corn flour has been stripped of protein, essential fatty acids, vitamins, and minerals.The scientific human origin story unfolds like a mystery novel as each riddle is solved. One riddle that needs to be figured out is when humans first used fire. Unfortunately the evidence of the most ancient fires hasn't survived, but archeologically there is good evidence of fires going back for 790,000 years.Another riddle is when did we first control fire? We couldn't have depended on cooked food until we could make fire from scratch, which probably happened first in a place where both flint and pyrite rocks existed. When struck together, they make excellent sparks and this method is used by hunter gatherers from the Arctic to Tierra del Fuego.We can also look at the skeletons of our ancestors going back 2 million years to see what and when changes in our anatomy happened. We know from the Grant's study of finches in the Galapagos and other research that evolution can happen very fast. It's likely that we evolved quickly once we became dependent on cooked food.There have only been three times in the past 2 million years when evolution was so fast that our ancestor species names changed. Atello and Wheeler believe that cooking was responsible for the transition from Homo erectus to homo heidelbergensis 800,000 years ago, but Wrangham believes this transition was much earlier, when Homo erectus emerged over 1.5 million years ago, and explains why and alternative theories for the other times we evolved quickly.Years ago Species.............Brain Size (Cubic inches)2,300,000 Homo habilis..........371,800,000 Homo erectus..........53..800,000 Homo heidelbergensis..73..200,000 Homo sapiens..........85It's the social ramifications of eating cooked food that may be of the most interest. A division of labor between men and women dramatically changed how we lived and related to one another, freed up time to pursue cultural activities, and made a much higher standard of living possible.But the dark side is that men used their larger size to get out of the most boring and worst chores. In 98% of all societies, past and present, women do most or all of the cooking. Even in the most egalitarian societies that have ever existed, like the Vanatina of the South Pacific, women did the cooking, washing dishes, fetching water and firewood, sweeping, and so on. Meanwhile the men sat on verandahs chewing betel nuts.It probably all started as a protection racket - men protected women from being robbed of their food by hungry groups of men in exchange for women cooking their meals.Bonobo females form fighting alliances to protect themselves from male bullying, but in all other great ape species, including ours, women lose out to men. Although Wrangham says that women can try to use their cooking as a form of empowerment by threatening to leave or not cooking if their husband is too abusive, I believe more than that is needed.I'm going to step up on a soapbox briefly now because I think the time when might makes right and men grow increasingly abusive is upon us. The days of less energy and scarce resources has arrived. In the future, the only way to get around male domination will be to create strong social support networks among women. For example, after the Chinese revolution in the 1940s, if a woman was beaten by her husband, the other women in her village jointly beat him up so he wouldn't do that again. (2)Back to the book. In Inuit societies, wives made warm dry hunting clothes, and spent many hours cooking. A man didn't have time to hunt, make clothes, and cook, so a wife was essential to survival. Desperate bachelors often tried to steal other men's wives, usually killing the husband. So men killed strangers on sight to prevent their wives from being stolen.In the Tiwi culture, old men got the young wives, so 90% of men's first marriages were to widows as old as sixty. But the young men didn't mind, because the wives cooked for them. In most societies, bachelors are miserable.In the end, Wrangham unravels far more than some of the riddles of the mystery of our creation, but also why we are getting so fat today, and the way that cooking and eating created how humans live and how men and women relate to each other.(1) Nina Jablonski. 2006. Skin, A Natural History. University of California Press.(2) William Hinton. 1997. "Fanshen: A Documentary of Revolution in a Chinese Village". University of California Press.

I first encountered Richard Wrangham some years ago, while searching the internet for information on when humans started cooking their food. I came across a video of a talk he gave at the International Association of Culinary Professionals 2005 International Conference called "The Natural Cook: The Significance of Paleo-Gastronomy". It was electrifying. I'd never heard this theory before, and it totally made sense. I bought the talk on CD and then went searching the internet for articles he'd written. So I was excited to see this book.The reason I was researching whether paleolithic people cooked is because the paleolithic diet defines "good nutrition". People argue endlessly about whether we should eat cooked food or raw, meat or vegetarian, low carb or high carb, etc. The answer to all questions such as these is found in the answer to this question: "What did we evolve eating?" What we are adapted to eat is what we should eat. I talk about this - and how the processed food industry turns our instincts against us - in my own book, "Normal Eating for Normal Weight".There's a movement of people trying to eat according to the paleolithic diet, and quite a few books attempt to describe what this is (e.g. The Paleo Diet: Lose Weight and Get Healthy by Eating the Food You Were Designed to Eat). The touchstone for what's paleo has always been, "Can you eat it raw?" since it was assumed that cooking came later in human evolution. Wrangham turns this touchstone on its head. If humans are human BECAUSE they cook, if there is no such thing as a human who didn't cook, then there's no reason to believe that we evolved eating only those foods that could be eaten raw.It was my hope that "Catching Fire" would give an outline of the paleolithic diet in light of this new "cooking" perspective. But it did not, and that is my one disappointment with the book. Traditionally, the paleolithic diet was thought to exclude grain, beans, potatoes, and milk products (and, of course, anything refined or factory processed). Grain, beans, and potatoes cannot be eaten raw, and wild animals cannot be milked. Are grain, beans, and potatoes still to be considered "not paleo" in light of the cooking hypothesis? What was the nutritional profile of the paleo diet - fat, carb, protein? What was the omega-3 to omega-6 ratio? I wish he'd addressed these issues.Sadly, the only aspect of our modern diet that he addressed was the calorie density of our food, and flaws in how we count calories. He said nothing at all about any other aspect of our modern diet. There is a lot more to nutrition than calories! The book ended with an endorsement of Michael Pollan's recommendation to eat whole, unprocessed foods, but I already knew that. I was hoping for specifics. Maybe Wrangham will write a second book that gives more detail on the nutritional profile of the paleolithic diet, especially as compared to the modern diet. An increase in calorie-dense food is by no means the only difference!That said, there is much to love in this book. The analysis is brilliant, it's extremely well-documented, and at the same time it's highly readable and often amusing. Some aspects of the theory are disturbing. He gives a very strong argument for how cooking led to a patriarchal social system where women serve men by performing the cooking and all other domestic tasks - a social system that persists to this day.This is a brilliant book and a great read. It's just oddly lacking in a nutritional profile of the paleolithic diet. I hope he follows up with a second volume.