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If you could travel back in time about 8 million years, you'd find a creature in an African tree that was the ancestor of all current apes and humans. And that creature in all likelihood would have spent a big part of its day munching leaves and fruit — pretty much what apes eat now.

Obviously, we humans took a differe

Grass: It's What's For Dinner (3.5 Million Years Ago)

By CHRIS JOYCE

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Credit iStockphoto.com

Some 3.5 million years ago, our ancestors put grass on the menu.

Originally published on Mon June 3, 2013 12:49 pm

If you could travel back in time about 8 million years, you'd find a creature in an African tree that was the ancestor of all current apes and humans. And that creature in all likelihood would have spent a big part of its day munching leaves and fruit — pretty much what apes eat now.

Obviously, we humans took a different course, so to speak. We've refined our palates over the course of time. Westarted to eat meat, though exactly when is a tough call; the first evidence suggests maybe 2.5 million years ago. We figured out how to make fire and then cook food, which was a big deal, since it helped digest things our stomachs couldn't deal with easily and also kill nasty stuff that hitchhiked on our rib-eye and made us sick.

But scientists now think they've found a dietary Rubicon that human ancestors crossed long before that.

A team of researchers spent years analyzing teeth from fossils of early humans as well as their ancient forebears, such as Australopithecus, the diminutive creature that walked upright, climbed trees, and lived a sort of part-ape, part-human-like lifestyle. What the team looked at specifically were the amounts of certain isotopes of carbon that get taken up from our food and deposited in our teeth. These isotopes reveal what we and our ancestors were eating.

Well, not EXACTLY what we were eating. What the tale of the teeth reveals is this: About 3.5 million years ago, our ancestors started switching from the ape diet — leaves and fruit — to grasses and grass-like sedges. In the terminology, they switched from C3 plants to C4 plants.

Says geochemist Thure Cerling from the University of Utah, one of the scientists who did the work: "For a long time, primates stuck by the old restaurants — leaves and fruits — and by 3.5 million years ago, they started exploring new diet possibilities ... that grazing animals discovered a long time before, about 10 million years ago."

It was about 10 million years ago that Africa's forests started to give way to open savanna. That meant more grasses, fewer leaves. So maybe primates pretty much had to go with the flow, though it took them a few million years to order from the new menu.

Now, one thing this carbon isotope technique can't tell is whether Australopithecus just grazed like a bunch of antelope, or whether they ate the antelope that did the grazing. The carbon signal from the C4 plants gets taken up in animal (or insect) tissue and passed on to whoever eats that tissue (thus, when we eat chicken, we're pretty much eating corn).

But scientists find this interesting nonetheless. Diet can be a powerful influence over the direction human evolution took. Says Cerling: "If diet has anything to do with the evolution of larger brain size and intelligence, then we are considering a diet that is very different than that we were thinking about 15 years ago," which is to say leaves and fruit.

You can read several papers on these findings in the latest issue of the Proceedings of the National Academy of Sciences.

So, what to make of this? Well, for one, those who favor a "paleo diet" that resembles what our early ancestors lived on might consider investing in a lawn mower. After all, lawn grass is probably America's largest unharvested crop — there's plenty to go around. Why not go back to our roots?nt course, so to speak. We've refined our palates over the course of time. Westarted to eat meat, though exactly when is a tough call; the first evidence suggests maybe 2.5 million years ago. We figured out how to make fire and then cook food, which was a big deal, since it helped digest things our stomachs couldn't deal with easily and also kill nasty stuff that hitchhiked on our rib-eye and made us sick.

But scientists now think they've found a dietary Rubicon that human ancestors crossed long before that.

A team of researchers spent years analyzing teeth from fossils of early humans as well as their ancient forebears, such as Australopithecus, the diminutive creature that walked upright, climbed trees, and lived a sort of part-ape, part-human-like lifestyle. What the team looked at specifically were the amounts of certain isotopes of carbon that get taken up from our food and deposited in our teeth. These isotopes reveal what we and our ancestors were eating.

Well, not EXACTLY what we were eating. What the tale of the teeth reveals is this: About 3.5 million years ago, our ancestors started switching from the ape diet — leaves and fruit — to grasses and grass-like sedges. In the terminology, they switched from C3 plants to C4 plants.

Says geochemist Thure Cerling from the University of Utah, one of the scientists who did the work: "For a long time, primates stuck by the old restaurants — leaves and fruits — and by 3.5 million years ago, they started exploring new diet possibilities ... that grazing animals discovered a long time before, about 10 million years ago."

It was about 10 million years ago that Africa's forests started to give way to open savanna. That meant more grasses, fewer leaves. So maybe primates pretty much had to go with the flow, though it took them a few million years to order from the new menu.

Now, one thing this carbon isotope technique can't tell is whether Australopithecus just grazed like a bunch of antelope, or whether they ate the antelope that did the grazing. The carbon signal from the C4 plants gets taken up in animal (or insect) tissue and passed on to whoever eats that tissue (thus, when we eat chicken, we're pretty much eating corn).

But scientists find this interesting nonetheless. Diet can be a powerful influence over the direction human evolution took. Says Cerling: "If diet has anything to do with the evolution of larger brain size and intelligence, then we are considering a diet that is very different than that we were thinking about 15 years ago," which is to say leaves and fruit.

You can read several papers on these findings in the latest issue of the Proceedings of the National Academy of Sciences.

So, what to make of this? Well, for one, those who favor a "paleo diet" that resembles what our early ancestors lived on might consider investing in a lawn mower. After all, lawn grass is probably America's largest unharvested crop — there's plenty to go around. Why not go back to our roots?

1. Yuri said:

   Thank you very much!

2. Theolana said:

   Dr. Axe, what are your thoughts on canned wild caught salmon and also canned tuna?

3. Glenn said:

   So how is it worst then bacon? What is wrong with bacon?

4. ann said:

   did you know this!

5. andrew said:

   So why do you have to bash bacon, where’s the backup evidence to support your claims that bacon is not good for you – I disagree!

6. John said:

   I’d like to see evidence that bacon or hamburger is inflammatory. I avoid teh same thing wild fish avoid: corn and soy but also wheat.

7. aCountryVegan said:

   I do appreciate you bringing to light the dangers of eating farm raised fish, but there are other healthy sources of Omega-3 fats, EPA and DHA without eating fish, including flax and chia seeds for the omegas and algae & seaweed for EPA and DHA. Also not everyone can afford to spend $16 to $35 a pound for fish from your online fish source. One ounce of Salmon has:
   total Omega-3 fatty acids 316 mg
   while one 1/4 ounce of ground flaxseeds has: total Omega-3 fatty acids 1597 mg
   At over $2 an ounce for the fish source you suggested and a little over 5 cents for the flaxseeds, I think I will stick to the flaxseeds.

   The nutrition data was from nutritiondata.self.com

8. Brent said:

   Because The Creator said so in Lev. 11 and Deu. 14.

9. Bambi said:

   Thank you for this article! I know pork is extremely unhealthy (its a scavenger, it will eat its own feces! After all, you are what you eat… including what they ate)! I also knew the way conventional beef and chickens are raised is unhealthy too but I didn’t realize so many of the same practices are used in farming fish! I can’t afford really good quality fish online, but I can afford the canned wild salmon. Also, my husband loves to fish, but even so you have to check with others to make sure which lakes are okay to eat the fish out of. I live in FL where there are plenty of lakes but some (especially in park areas where lots of people are at) are too poluted to eat the fish. If you don’t agree about conventional meat being unhealthy for you, I seen a couple of documentaries that will turn your stomach called “Frankensteer” and “A River Of Waste” (both can be found on Netflix too).

10. Susan said:

    I was at a health conference in Atlanta where Dr. Axe was teaching along with Jordan Rubin and Dr. Caroline Leaf. I actually asked this same question and Dr. Axe said he is fine with canned wild caught salmon and finds it to be an affordable alternative to fresh.

11. Dennis Valverde said:

    Thanks Dr. Josh Axe I’ll keep that in Mind
    I Take fish oil omega 3 gel caps with D3 in it.
    I will try the wild sockeye salmon.

12. Stephen said:

    A note on pork poop:

    Not only will hogs eat their own feces, but, many animals do so when food is scarce or they’re under nourished.

    When hogs are humanely raised thru organic methods, rarely, if at all, will they eat their own feces.

    Basically, any conventionally raised animal, regardless, if it is on a family farm or commercial farm, is all bad. Don’t be fooled by the “family farm” hype.

    We have been involved with humane animal practices and organic farming for sometime and it’s very frustrating to see so many farmers are claiming to have organic methods, free range and grass fed. That’s only on the surface!

13. Theolana said:

    Thank you Susan!!

14. Christy said:

    What about the bpa in the lining of cans??

15. Liz said:

    I have been wondering about the safety of Alaskan Salmon lately, due to the radiation from Japan. Do you have any info about that? I haven’t found too much info online about this issue.

16. Wade said:

    I do think you should look into the The Weston A. Price Foundation’s articles on Fish Oil_in the U.S. a naturally produced, unheated, fermented high-vitamin cod liver oil that is made using a filtering process that retains the natural vitamins.
    The high-vitamin fermented cod liver oil is sold as a food so does not contain vitamin levels on the label. However, after numerous tests, the approximate values of A and D have been ascertained at 1900 IU vitamin A per mL and 390 IU vitamin D per mL. Thus 1 teaspoon of high-vitamin fermented cod liver oil contains 9500 IU vitamin A and 1950 IU vitamin D, a ratio of about 5:1.

17. Lesley said:

    I am quite concerned about any fish coming out of Alaska or the Pacific right now due to the radiation from Fukushima. Most of the fish from the web site recommended in this article is from the Pacific. Do you recommend any other sites where we can purchase non-Pacific, non-Alaskan wild caught fish?

18. Jill said:

    Yes, I would like to know this too.

19. Jill said:

    “The Creator” also outlined the proper procedures for selling daughters into slavery…

20. Guerry said:

    Thanks, Dr for the info. Change in my fish
    diet right away.

21. mare brennion said:

    i find really good wild caught (sometimes fresh) fish at harris teeter on hwy 100, and they will answer questions about them.

22. Nancy said:

    What about aquaponics? See http://heavytable.com/greens-in-winter-cold-weather-farming-in-minnesota/
    Are you condemning all farmed fish?

23. Maple said:

    Dr. Axe, what brand of canned wild caught salmon and canned tuna do you recommend?

24. Travis said:

    Wild fish may be better for you but it’s really not a viable option for anyone that cares about the environment. Wild fishing is notoriously hard to regulate and as a result most of our fisheries have been wiped or are on track to be depleted within decades (http://www.washingtonpost.com/wp-dyn/content/article/2006/11/02/AR2006110200913.html) .

    The last thing we need is for everyone to get it in their head that they should only eat wild fish. I agree that conditions at farms should be better but that’s no reason to go wiping out species.

25. Dylan said:

    When I go to check out vital choice as a source of Wild Salmon, it says that it is Sustainably Harvested. Isn’t that just another way of saying Farmed?

26. tracy said:

    I am interested in all the perspectives, but choosing an acceptable balance between price, quality, taste, ease of purchase, nutritional value, and availability is sometimes just an exercise in futility.

    Gotta die of something, right?

    I guess I’ll have my bacon burger with a side of tilapia, a multivitamin and a eulogy.

27. Marilyn said:

    My son lives in Fairview and has 15 acres. He has free range chickens that run all over the yard and eat poop and all kinds of worms and bugs. So, I buy good eggs at Kroger.

28. Dr. Loren Marks said:

    I can appreciate your cost conversion on omega 3s from a vegetarian source to a animal one, but you fail to realize that it is not the same comparison. The value of both are derived from their EPA/DHA content. Vegetarian sources have been studied and Schmit at NASA Ames has published data that states that for every one hundred molecules of flax seeds, only 1 can be converted into EPA/DHA. Additionally, it is a long and arduous metabolic pathway requiring many nutrients as co factors for this conversion to occur. If you don’ t want to eat the fish, for your vegan diet, consider taking the fish oil. But do continue to eat the seeds for their lignans.
    Best,
    Dr. Marks

29. Fisher said:

    You could always go fishing too.

30. Rita Maggi said:

    Recently I was in the Caribbean snorkeling and instead of viewing a beautiful reef, I viewed old shoes, plastic bottles and glasses, tin cans, etc.Not to mention that tons of garbage and nuclear waist is polluting our vast ocean resource. Therefore, I don’t understand how fish caught in the wild is any better than farm raised.

31. Ginny said:

    Chickens naturally work through manure to find bugs and seeds. Their digestive systems are designed to eat those things. Your son’s free-range chickens are living a much healthier life than the chickens who provide eggs for grocery stores. Those chickens are kept in confinement, kept awake 23 hours a day, have their beaks filed down (to prevent cannibalism), and are fed a steady diet of soy, corn, antibiotics, hormones, and chemicals. So you’re much better off with your son’s eggs.