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Our Human Ancestors Were Vegetarian?

Our Human Ancestors Were Vegetarian

Artificial colors. Artificial flavors. Artificial sweeteners. High fructose this. Partially hydrogenated that. Few would argue that the “food products” found on most grocery store shelves these days are anything close to natural.

In fact, most of these products didn’t even exist just a few decades ago. Take high fructose corn syrup, for example. Hard to believe, but the now-ubiquitous HFCS only went mainstream about 30 years ago.

A few decades can seem like an eternity in the context of a human life, but it’s a blink of an eye on the scale of the Earth’s history and timeline. So it’s no wonder many people worry about the impacts of our rapidly-changing diets on our slowly evolving bodies. And this concern has predictably led to…you guessed it, new diet books!

“Paleolithic diets have become all the rage, but they are getting our ancestral diet all wrong,” notes biologist and writer Rob Dunn in a recent piece for Scientific American.

So-called Paleolithic diets are an attempt to mimic the eating style of Paleolithic man. If you couldn’t hunt it or gather it you couldn’t eat it. There was no agriculture – plant or animal – no processed foods, no grains, and no shipping in bananas from Central America. These diets are typically classified as “low carb” and emphasize meat, fish, nuts and seeds, and certain fruits and vegetables.

While researchers disagree about the prominence of meat in the diet of Paleo man, Dunn aptly points out that it may not actually matter. He explains:

“…if we want to return to the diet our guts and bodies evolved to deal with, we should not be looking at our most recent ancestors. Instead, we need to understand the diet of our ancestors during the time when the main features of our guts, and their magical abilities to turn food into life, evolved. We need, in other words, to look at apes, monkeys and other non-human primates.”

He also points out that the digestive systems of modern man are remarkably similar to those of gorillas, chimpanzees, monkeys, and apes. And their diets consist mainly of fruit, nuts, leaves, and insects, and the occasional bird or lizard. Overall, however, meat makes up less than three percent of their dietary intake.

Thus, this dietary composition mimics the way our ancestors spent the most time eating during the largest periods of the evolution of our guts. And it hardly sounds low carb.

So what should we be eating? Dunn quips about giant sloths, mastadons, insects, and even feces. But fruit, nuts, seeds and greens sound like a pretty solid base. Throwing in a few foods your ancestors wouldn’t recognize probably won’t kill you, but they shouldn’t be staples in your diet.

Image Credit: Scientific American

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6 comments on “Our Human Ancestors Were Vegetarian?”

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Elise Marie
6 Years Ago

This article offers an interesting perspective on the evolution of humans. I have also read that early humans did not in fact have canine teeth rather had a mouth more like a horse would. The body evolved to having canines to accommodate to the humans change in diet. This article correlates with that fact. Ever since becoming vegan, my body has never felt better, and I feel good knowing that my diet is reducing the risk of diabetes, heart disease and obesity.

Doug @ HealthHabits
6 Years Ago

The author is neglecting the link between the evolution of the human brain and the human gut.. The Expensive Tissue Hypothesis contends that the increase in brain size in humans is balanced by an equivalent reduction in the size of the gastro-intestinal tract. In other words, the increased energetic demands of a relatively large brain are balanced by the reduced energy demands of a relatively small gastro-intestinal tract. This relationship also seems to be true in non-human primates. The size of the gastro-intestinal tract is dependent on both body size and the quality of the diet. It is argued that humans (and other primates) could not have developed a relatively large brain without also adopting a high quality (ie protein) diet that would have permitted a reduction in the relative size of the gastro-intestinal tract. Dietary quality has played a prominent role in theories of human evolution in general and the evolution of the human brain in particular. One of the most memorable of these theories is the ‘Man the Hunter’ (Ardrey, 1961; Washburn and Lancaster, 1968). This theory argued that increasing amounts of meat in the hominid diet lead to increasing levels of cooperation among the males in the hunt, which lead to brain expansion and the associated development of cognition, language and symbolic culture. This hypothesis was fuelled by the realisation that an increase in the apparent consumption of meat correlated with the increase in brain size seen in Homo habilis and Homo erectus. It was also supported by the recognition in the archaeological record of the basic elements of a hunter-gatherer life-style (home bases and food sharing) (Isaac, 1971). Although the rather simplistic reasoning underlying the ‘Man the Hunter’ hypothesis has lost favour in more recent years (eg. Tanner, 1981; Power and Aiello, in press) the importance of a high quality diet, and meat eating in particular, has been a common theme (eg. Foley and Lee, 1991; Leonard and Robertson, 1992, 1994).

6 Years Ago

I'm sorry, but how does the title of this post relate in any way to its contents? The article itself clearly states that a) we're not talking about our HUMAN ancestors but about our APE ancestors, and b) animals eating 3% meat are obviously not vegetarians. Why is it that many vegans crack down on 'fake vegans' saying they're vegan while they 'cheat', while bending the truth in order to sound more convincing is okay? I love following the posts on this website, but I'm disappointed at the way this article tries too hard to bend scientific research into vegan propaganda. Veganism doesn't need that. Veganism doesn't even need vegetarian or semi-vegetarian ancestors. They might as well have been fulltime mastodon-eaters, it's irrelevant. Natural is not always good, good is not always natural. We're omnivores by nature (this is not my opinion, it's the consensus in the scientific field of palaeoanthropology, in which I happen to be working). What being an omnivore means is; we can choose from a wide range of food choices. Let's make the one that's best for our health, animals, and the planet.

24 Jul 2012

Thank heavens Renee, a voice of reason!! Thank you!! Human ancestors were not vegetarian, omnivore people, omnivore, get it? Veganism is a concious choice not a return to an ancestral way of eating, also we have been divergent from a common ancestor with other great apes for millions of years, long enough or us BOTH to evolve along our pwn lines. The guts of humans and great apes are similar in the fact that yes, they are guts, but there are major differences, for more information I point you to the 'expensive tissue hypothesis' by Aiello and Wheeler, 1995. Enough of the congratulatory back-patting oh vegan world, it's your choice, live it and be personally proud but we need to get off our collective high horse and stop propagandising. Ok, done.

Jennifer Valentine
25 Jul 2012

The purpose of this article was simply to note that our ancestors probably ate more plant-based foods than previously thought and that many of our closest biological relatives eat a diet consisting mainly of fruit, greens, nuts and seeds. Not that we need vegetarian or vegan ancestors, but that this type of diet could be evolutionarily appropriate. The message is that we’d all be doing well to include more of the good stuff in our diet (fruit, greens, nuts, and seeds) and less of the health- and planet-wrecking bad stuff. Thanks for reading!

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