This fascinating review of Richard Wrangham's Catching Fire: How Cooking Made Us Human makes me think of The Road (in which father and son, seemingly the last truly humans on earth, describe themselves as "carrying the fire"), Lord of the Flies (in which fire is the boys' only hope of rescue but also part of the violent and carnivorous impulses that distract them from keeping their signal burning), and Greg Brown's great song "Telling Stories" ("Everyone is scared, everyone’s alone/unless hand reach for hand when the trouble comes/all around the world when the dark night falls/we should be sitting around the fire telling stories").
Here the reviewer outlines Wrangham's thesis:
Apes began to morph into humans, and the species Homo erectus emerged some two million years ago, Mr. Wrangham argues, for one fundamental reason: We learned to tame fire and heat our food.
“Cooked food does many familiar things,” he observes. “It makes our food safer, creates rich and delicious tastes and reduces spoilage. Heating can allow us to open, cut or mash tough foods. But none of these advantages is as important as a little-appreciated aspect: cooking increases the amount of energy our bodies obtain from food.”
He continues: "The extra energy gave the first cooks biological advantages. They survived and reproduced better than before. Their genes spread. Their bodies responded by biologically adapting to cooked food, shaped by natural selection to take maximum advantage of the new diet. There were changes in anatomy, physiology, ecology, life history, psychology and society.” Put simply, Mr. Wrangham writes that eating cooked food — whether meat or plants or both —made digestion easier, and thus our guts could grow smaller. The energy that we formerly spent on digestion (and digestion requires far more energy than you might imagine) was freed up, enabling our brains, which also consume enormous amounts of energy, to grow larger. The warmth provided by fire enabled us to shed our body hair, so we could run farther and hunt more without overheating. Because we stopped eating on the spot as we foraged and instead gathered around a fire, we had to learn to socialize, and our temperaments grew calmer.