Richard Wrangham argued in his 2009 book, “Catching Fire: How Cooking Made Us Human” that when our ancestors learned to cook food, it changed how they developed:
Wikipedia, Catching Fire: How Cooking Made Us Human
Humans (species in the genus homo) are the only animals that cook their food and Wrangham argues Homo erectus emerged about two million years ago as a result of this unique trait. Cooking had profound evolutionary effect because it increased food efficiency which allowed human ancestors to spend less time foraging, chewing, and digesting. H. erectus developed a smaller, more efficient digestive tract which freed up energy to enable larger brain growth. Wrangham also argues that cooking and control of fire generally affected species development by providing warmth and helping to fend off predators which helped human ancestors adapt to a ground-based lifestyle. Wrangham points out that humans are highly evolved for eating cooked food and cannot maintain reproductive fitness with raw food.
Cooking is a form of food processing. So is grinding. So is chewing although as we saw with almonds, chewing isn’t as effective as other forms; some of those almonds and their fat and calories get excreted.
Food processing breaks down cell walls and decreases the size of food particles (increasing their surface area), giving digestive juices and enzymes more product to work on. It increases availability of nutrients that would otherwise go right through us. We absorb more, with less effort, and we absorb it faster. This can be a good thing, as Wrangham describes, or it can create problems, as we saw in the rats in my previous post.
Processing food by cooking was clearly an advantage for early humans. What were they cooking? Everything, but starches took center stage, so much so that:
Compared with chimpanzees, humans boast many more copies of the gene that makes salivary amylase — a saliva enzyme that breaks down starch into digestible sugars.” … “High starch foods and a high starch diet have been an important evolutionary force for humans,” says George Perry, an anthropologist at Arizona State University.
Here’s a new study:
Earliest Evidence Of The Cooking And Eating Of Starch, Eurekalert, 17 May 2019
New discoveries made at the Klasies River Cave in South Africa’s southern Cape, where charred food remains from hearths were found, provide the first archaeological evidence that anatomically modern humans were roasting and eating plant starches, such as those from tubers and rhizomes, as early as 120,000 years ago.
The new research by an international team of archaeologists, published in the Journal of Human Evolution, provides archaeological evidence that has previously been lacking to support the hypothesis that the duplication of the starch digestion genes is an adaptive response to an increased starch diet.
“Our results showed that these small ashy hearths were used for cooking food and starchy roots and tubers were clearly part of their diet, from the earliest levels at around 120,000 years ago through to 65,000 years ago,” says Larbey. “Despite changes in hunting strategies and stone tool technologies, they were still cooking roots and tubers.”
“Starch diet isn’t something that happens when we started farming, but rather, is as old as humans themselves,” says Larbey. Farming in Africa only started in the last 10 000 years of human existence.
“Evidence from Klasies River, where several human skull fragments and two maxillary fragments dating 120 000 years ago occur, show that humans living in that time period looked like modern humans of today. However, they were somewhat more robust,” says Wurz.
What I’m saying here is that processed foods are a good thing. We evolved to eat them, especially starches. The problem with modern processed foods is that during the course of processing, things are taken away or added. We have created food we didn’t evolve to eat. It’s wrecking havoc with our health. I’ll talk about that in my next post.
Here’s a fantastic video I found of a man who cultivated a yam and cooked it using no modern tools. Something else. Source: Yam, Cultivate and Cook.