In part one of WTF are Tiger Nuts? I talked about what exactly Tiger Nuts are in the botanical sense. In this installment I am going to talk about some of the claims regarding the ancestry of Tiger Nuts in our diet.
Depending on where you have heard about Tiger Nuts, you may have been lead to believe that Tiger Nuts comprised a large portion of our “Paleo ancestor’s” diet, perhaps even up to 80%.
Unless something has changed wildly in the research or our understanding of human evolution, the claim that our Paleo ancestors ate Tiger Nuts almost exclusively, is playing a bit fast and loose with the science. Ok, we are about to go down a bit of a paleoanthropological rabbit hole, but I’ll try to be as clear as possible.
Very early last year (2014), in January to be exact, an article was published in PLOS ONE by Dr. Gabriele A. Macho. This article has some very interesting theories about the diet of a specific early hominin, Paranthropus boisei, who is referred to as Nutcracker man for convenience. Dr. Macho suggests that by using carbon analysis, modern primate parallels, and dento-cranial morphology (the size and shape of the teeth, jaw and head) we can perhaps reconstruct what Nutcracker man ate. As with all research, Dr. Macho’s work is built upon the theories of the others and she makes no claims that her own work is precise or definitive.
It is compelling however and the jist of it is that Nutcracker Man could have, and quite possibly did, derive up to 80% of his diet from eating Sedge grass tubers, like Tiger Nuts. But there are two things that need to be kept very, very clear: at the moment, this is just a theory; and that this research does not necessarily tell us anything about what our direct ancestors ate.
This research has been used to imply that Tiger Nuts were a large part of modern man’s Paleo forefather’s diet. That claim is based on rather shaky ground. I assume that the claim is made because it is rather complicated to fully understand what the research means and most people don’t have the time to untangle it. I will attempt to provide a brief run down to help clarify.
Here is the long and the short of it, Nutcracker Man, P. boisei, is not a direct ancestor of modern man, at least as far as we currently understand our evolution. He was more like a cousin of our direct ancestor. Paleoanthropology is not exact and our lineage is not fully established; however, except for a brief period after it’s first discovery, Nutcracker Man has never been considered our direct ancestor.
Nutcracker Man was a hominid/hominin, which means that he was more closely related to humans than chimpanzees and in the broad sense is an “ancestor” in that he evolved before us and is one of the many species whose existence and eventual extinction was a part of the evolutionary puzzle that eventually allowed for the rise of Homo sapiens. But that is not the same thing as being a direct ancestor.
I think that the best example of why this is such an important point to understand is the Nutcracker Man’s jaw. It is his jaw that gave him the name Nutcracker Man in the first place.
The lower jaw of P. boisei from http://australianmuseum.net.au/paranthropus-species
It is this jaw that helps to justify the theory that Nutcracker Man lived on primarily Sedge tubers – without such a robust jaw, thick dental enamel, and massive cheek teeth, Nutcracker Man probably wouldn’t have been able to survive on this diet. The biggest mystery of Nutcracker Man was what his jaw was designed to eat, and I think the theory of Sedge tubers makes a lot of sense – for Nutcracker Man.
However, the jaw of Nutcracker Man was not the jaw of our ancestors. The jaw, teeth and skull of Nutcracker Man allowed him to quite possibly subsist on a diet made up almost entirely of Sedge tubers, but it was this diet that is suggested as part of his eventual downfall. In a world of food competition it served the Nutcracker Man to eat a part of the plant that would have been difficult for other hominins to consume; it provided him with a food source without competition. But when these food sources disappeared for one reason or another the specialized jaw of Nutcracker Man became his downfall – he could not adapt as well to the new environment that no longer provided the food he had adapted to. But our ancestors did adapt, because they were not specialists and could adjust better to the new environment.
None of this is to say that we as modern humans therefore cannot or should not eat Tiger Nuts. Perhaps our direct ancestors ate some occasionally, I know I do. But I think it is important to fully understand the claims being made about Tiger Nuts.
Next time we’ll talk more about the recent history of Tiger Nuts as food and why you might want to start snacking on them from time to time.
For those interested, you can find a quick and dirty list of my resources here. I'll admit it's not the best bibliography I've ever written but hopefully it provides some reading suggestions if you want to look a bit further.