Interesting article about human ancestors eating grass: [URL="http://www.sciencedaily.com/releases/2013/06/130603163749.htm"]A Grassy Trend in Human Ancestors' Diets[/URL].
The implication is that our ancestors have eaten grasses right along. But the following statement is important. It would come as no surprise that our early ancestors were eating nutrition-packed roots and rhizomes.
[QUOTE]The isotope method cannot distinguish what parts of grasses and sedges human ancestors ate -- leaves, stems, seeds and-or underground storage organs such as roots or rhizomes. [/QUOTE]
From skimming it doesn't really seem like they know what they are talking about.
The readings could have meant they ate 1) the grass, 2) the tuber/roots of the grass, 3) the animal that ate the grass.
They don't know.
So why not assume they ate meat and potatoes? Why did they assume they ate grass?
The answer's probably all 3.
As a kid, and even now, I occasionally chew on and swallow common grasses. They're often kind of sweet, especially the stalkier ones.
Not impressed. An isotope here or there does not a diet make. What if you wanted to eat grass today? First there are toxic grasses, the usual toxin is cyanide. Sorghum leaf blades has some cyanide, crowfoot grass seeds have some cyanide. If we want to eat grass today we have to choose carefully. Native North American grasses are not toxic, but several imports are. Next, we don't have the multiple (bovine) or extra large (equine) stomachs to digest and extract what few nutritments there are in grass. However, grass blades and stalks can be dried, powdered, and used as a bulking agent in bread, soups, meatloaf et cetera. But I doubt they were doing that in the study's time frame.
Sedges are a bit different in that it is said all sedge seeds are edible. They are usually quite small but they come into season all at the same time and are easy to collect so it is a calorie positive activity but barley because of size. Some of them do have some sugar or starch in their roots. A few of them are toxic as well. Sedges are more understandable as food in that they usually grow in or near water, and early man did not wander far from water.
I earn my living teaching people how to forage for wild plants. Setting aside primal blueprint reservations about grains grains are not always worth the effort. Barnyard grass is a good example. While it can be used like wheat it take a huge amount of work to get it harvested, winnowed, stored, cooked et cetera. It is calorie positive but not greatly so. It is also not a readily nomadic food. It takes processing that that usually requires staying on one place a while.
On the other hand a vegetable root usually has far more calories and requires far less work. Sea kale root is an excellent example. A million years ago when you either found food or lost weight or died. I can't see grains as a staple source of calories. Roots yes. Easy to find, little work to dig up, big pay off, many were and can be eaten raw. No fire needed. Grains I would think would be what we call today a trail side nibble. A few here, a few there. Not a staple. That would be enough to leave an isotope or two. I am willing to bet if they looked for root vegetable isotopes they would find better evidence of our early diet.
In research looking at 10,000 years ago et cetera the confounding element is the non-digestability of grain. A few grains of wheat will store a few thousand years better than a primitive potato. Because grains were found the assumption has always been grains were the first cultivated crop and the main crop. Perhaps in some place of the world that is true but in other areas roots may have been the first grown food. From a calories in calories out point of view roots top grains easily, today and no doubt in the past. Grok would have dug up roots long before he collected grain.
Thanks for the detailed answer, Deane. I agree.
I like this quote the best. [quote]There is a slight chance that these early hominin specimens merely ate animals that ate grass. But because most primates don't have "diets rich in animal food... ," argues Lee-Thorp, "we can assume that [early humans] ate the tropical grasses and the sedges directly."
[/quote] [url=http://theweek.com/article/index/236487/did-early-humans-eat-grass]Did early humans eat grass? - The Week[/url]
[QUOTE=Knifegill;1213689]I like this quote the best. [url=http://theweek.com/article/index/236487/did-early-humans-eat-grass]Did early humans eat grass? - The Week[/url][/QUOTE]
Lol.... love that they can ASS- U- ME that ;)
From the OP article:
If early humans ate grass-eating insects or large grazing animals like zebras, wildebeest and buffalo, it also would appear they ate C4 grasses. If they ate fish that ate algae, it would give a false appearance of grass-eating because of the way algae takes up carbonate from water, Cerling says. If they ate small antelope and rhinos that browsed on C3 leaves, it would appear they ate C3 trees-shrubs. Small mammals such as hyrax, rabbits and rodents would have added C3 and C4 signals to the teeth of human ancestors.
Like Green Deane said, "Not impressed".
So basically if they studied carbon isotopes in fossilized tooth enamel of modern humans they would conclude that we are all corn eaters. Right?
[QUOTE=aliphian;1214357]So basically if they studied carbon isotopes in fossilized tooth enamel of modern humans they would conclude that we are all corn eaters. Right?[/QUOTE]
Yeah, they would. It's in everything.