Human Brain and Food

Human biological, social, and cognitive evolution has depended on food. That much seems obvious, but what is less obvious is the specific ways that first fire, and then agriculture, and then the combination of advanced cooking and food preservation methods have contributed to the quality of the human brain and the efficacy of the human body. Even at its most basic, cooking transforms the available nutrients in plants, and renders some otherwise inedible plants both edible/nonpoisonous or better able to provide bioavailable nutrients. Even just sticking plants and animal parts into a fire and waiting for a transformation to take place fueled human biological evolution because "cooking made available to our ancestors unprecedented nutrients that fueled brain growth over time, and reduced the need for energy-expensive chewing of tough foods," (King). Bioavailability increases from just 30 to 40% of nutrients in raw plants to a full hundred percent (Mott). Cooking transforms the food by making more nutrients available in a smaller food mass, condensing not just calories but nutrients. Cooking also transforms food in ways that were critical for the human body's evolution, such as by softening tough fibers, hastening the digestive process, and even releasing flavors -- enhancing the taste buds.

The archaeological record concurs with the more immediately understandable elements of food science and food chemistry. About 1.8 million years ago, the human brain grew exponentially, launching homo erectus ahead of the other primates. The innovation of cooking explains the transformation: "Homo erectus, considered the first modern human species, learned to cook and doubled its brain size over the course of 600,000 years," (Mott). The biological evolution of humanity has depended on the advent of cooking.

Yet increases in brain mass alone do not account for the advances in human cognitive powers. As Mott points out, brain matter is "more expensive tissue," because it "costs" more calories to maintain. The "fork in the evolutionary road," so to speak, is encephalization. Human beings started to favor a larger brain in a smaller body rather than the other way around. Concurrent with the advent of fire and cooking, the larger brain also made cognitive processes surrounding hunting and gathering more sophisticated. The concept that plants grow where their seeds fall led to the first conscious attempts at growing, followed by the evolution of human social structures and institutions that enabled agriculture. Agriculture only developed where it was necessary and/or possible; if a society was located in a nutrient dense zone, where hunting and gathering required relatively little energy expenditure, and reliable food sources all year, then there was no need for agriculture. When there were seasonal variations in foods, or when energy expenditures on food sourcing outweighed the energy inputs of the found food, agriculture started to become a promising new means of evolving in tandem with the environment. Agriculture changed human diets in radical ways, as humans in agricultural societies favored plants that responded well to their husbandry efforts. Similarly, human beings favored animals that lent themselves well to herding.