Nutcracker Man’s Diet Was Rich in Brain Food After All

The enigmatic diet of our supposed evolutionary cousin, Paranthropus boisei (aka “Nutcracker Man”), has long puzzled anthropologists. His big flat molars set in a massive jaw seemed suited for smashing nuts—hence the nickname. Recent studies of the carbon isotopes embedded in Nutcracker Man’s tooth enamel, however, belie that conclusion. Analysis shows he subsisted on plants like tropical grasses and sedges. But how could this extinct branch of the hominin1 family with a brain just a bit bigger than Lucy’s have prospered for a million years nibbling on rabbit food?

Nutcracker or Not?

Oxford University’s Gabriele Macho, ScienceDaily reports, has solved Nutcracker Man’s nutritional mystery. Dr. Macho has shown that baboons get along nicely on a diet rich in tiger nuts. In fact, bright young baboons actually supplement their mother’s milk by selecting tiger nuts from their smorgasbord of wild options, despite their clumsiness and lack of skill at digging the things out of the ground.

Tiger nuts are the nutritious underground tubers of sedges. So was Nutcracker Man a nutcracker after all? Surely he was as bright as a baboon. What kind of man was he, anyway?

This is a cast of the “Nutcracker Man” cranium originally discovered in 1959 by Mary Leakey along with a robust jaw found later. The massive jaw and large flat molars with abrasions led early anthropologists to believe Paranthropus boisei lived on nutritious nuts. More recent analyses of the teeth show that they weren’t used on nuts but rather to eat grasses and sedges, vexing evolutionary anthropologists with the idea that our presumed evolutionary cousins grazed like cows. Image by Durova, via Wikimedia Commons.

Saga of the Nutcracker Man

Paranthropus boisei, originally called “Dear Boy” by Mary Leakey who found its skull in 1959, acquired a more animated nickname when a lower jaw became available for study. The massive jaw and wide face accommodated huge flat molars with signs of wear. Those big flat teeth were reminiscent of an old-fashioned nutcracker. Thus, with the dubious addition of a slender bipedal body inherited from australopithecines (like Lucy), the evolutionary picture—Paranthropus boisei climbing up the human ancestral tree with his brain growth fueled by nutritious nuts—seemed complete. All that was missing, so it seemed, was a reason why Nutcracker Man’s branch of the family finally died out.

(Incidentally, the latest research on Nutcracker Man’s body demonstrates that he was neither a nutcracker nor a slender primate strolling about East Africa’s savannah. He was more likely a powerful arboreal swinger with strong arms and legs to match his robust jaw. But that’s a different story. . .  )

Brain Food

When evolutionists today try to explain how our presumed ape-like ancestors evolved a big enough brain to become human, they generally focus on their feet and their food. Did ape-like creatures first learn to walk upright, freeing their hands for more intellectual pursuits and prompting the evolution of a bigger brighter brain? Or did ape-like ancestors—in an early version of your mother’s admonition that you need brain food at breakfast to do your best at school—gather around the campfire, cooking tasty nutritious food to supply lots of calories with the added bonus of social interaction to fuel a sense of community?

Salad of Sedges

The satisfying saga of Nutcracker Man’s nutritional choices seemed to crumble, even for evolutionists, when modern scientific analysis of Nutcracker Man’s big teeth showed he didn’t eat nuts after all. Not only did the scratches on his teeth not match the abrasions that nut-crunching should have caused, but the carbon isotopes in his fossilized tooth tartar are the kind found in tropical grasses and sedges, not nuts.

Tropical grasses and sedges supply plenty of fiber, but they seem an unlikely diet for one of humanity’s cousins. As one paleoanthropologist involved in one of the tooth studies remarked, “Frankly, we didn’t expect to find the primate equivalent of a cow dangling from a remote twig of our family tree.”2

A Bit of Botany

Yellow Nutsedge. Image by Blahedo, via Wikimedia Commons.

Chufa. Image by Justass, via Wikimedia Commons.

This is a typical sedge, Cyperus esculentus. Cultivated for thousands of years, it also grows wild in temperate and subtropical regions of the northern hemisphere. This plant is valued for its edible tubers (shown on the right) commonly known as tiger nuts. Baboons in Kenya, according to a recent study, value tiger nuts as much nutrition-conscious people do, suggesting tiger nuts also may have met the nutritional needs of the extinct ape known as “Nutcracker Man.”

Plants use carbon dioxide to make useful compounds, beginning with glucose sugar. Through photosynthesis, carbon is “captured” to build glucose molecules. The first steps of photosynthesis vary, though the final product is the same. Most plants, including those that make nuts, first form a three-carbon compound and are therefore called “C3 plants.” Some plants, including tropical grasses and sedges, start photosynthesis by making a four-carbon compound. They are called “C4 plants.”

Most carbon atoms are carbon-12. A few are carbon-13, a non-radioactive form of carbon with one extra neutron per atom. C3 plants discriminate against carbon dioxide containing the heavier carbon-13 atoms. Nuts are the products of C3 plants. Tiger “nuts” are root-like tubers, not nuts. They have no shell, and they are not really nuts at all. Sedges, which are C4 plants, make tiger nuts. Therefore, tiger nuts contain the same isotopes as the grassy sedge above ground. Carbon isotopes in tooth enamel can reveal whether a tooth’s owner—though long dead—spent a lot of time chewing C3 or C4 plant material. The isotope proportions in enamel drilled from Nutcracker Man’s teeth show he didn’t have a nutty diet but could have had a “tiger nutty” one.

Naturally Nutritious

With no Nutcracker Man around for a nutritional inventory, Macho did the next best thing. She looked at the diet of wild one-year-old baboons in Kenya’s Amboseli National Park. Animals seem to opt for decent nutritional choices when allowed to range freely. She assumes Nutcracker Man’s native habitat would have been pretty much like that in the park, without the border protection of course.

Baboons, it turns out, eat lots of tiger nuts. The carbon isotope proportions in tiger nuts match those of the grassy sedges above ground, but the nutrition available from them is considerably better for a primate. Tiger nuts have plenty of starch, vitamins, minerals, and fatty acids. Sedges grow wild but have been cultivated for thousands of years, being highly valued for their nutritious tiger nuts.

Even given the time it takes to dig up the tubers, Macho calculated that Paranthropus boisei could have found enough calories and nutrients to fuel an evolving brain, but only if it chewed the food for a long time. Starch digestion begins in the mouth using the enzymes in saliva, so extensive dental grinding and mixing with saliva would have been needed to make the nutrition in uncooked tiger nuts fully available to Nutcracker Man. (Perhaps this is the origin of the proverbial wisdom advising you to chew your food a hundred times before you swallow.3)

Such long bouts of chewing are tough on the teeth and jaws, leading to the development of strong jaw muscles as well as abrasions on the teeth. Baboon teeth show this sort of wear and tear. Macho suspects the nutritional choices of baboons has revealed something of the Paranthropus boisei lifestyle and explained why Nutcracker Man’s cranial and dental features evolved as they did. She further suspects the baboons have solved the mystery of how such a “man” could survive for a million years on grass.

“Not all C4 foods are low quality,” Macho writes. “Hominins,4 like baboons, are likely to have been selective in their food choice. Which C4 foods were habitually consumed can only be determined on the basis of morphology, including body mass and brain size, and in conjunction with an animal’s energetic requirements.”5 She points out that another hominin that ate sedges, Australopithecus bahrelghazali, had buttressed teeth with thin enamel and therefore likely evolved to subsist on different C4 plant parts.

“I believe that the theory—that ‘Nutcracker Man’ lived on large amounts of tiger nuts—helps settle the debate about what our early human ancestor ate,” Macho explains. “On the basis of recent isotope results, these hominins appear to have survived on a diet of C4 foods, which suggests grasses and sedges. Yet these are not high quality foods.”

Noting that Nutcracker Man evidently had as much nutritional savvy as a baboon, Macho says, “What this research tells us is that hominins were selective about the part of the grass that they ate, choosing the grass bulbs at the base of the grass blade as the mainstay of their diet. Tiger nuts, still sold in health food shops as well as being widely used for grinding down and baking in many countries, would be relatively easy to find. They also provided a good source of nourishment for a medium-sized hominin with a large brain. This is why these hominins were able to survive for around one million years because they could successfully forage—even through periods of climatic change.”

Sorting Fact from Fiction

Neither Macho nor Science Daily explores the question of why Nutcracker Man’s line went extinct instead of living on to evolve into us, but to be consistent we could perhaps suggest that if he’d learned to cook his food and release the nutrients without all that chewing, he might have had time to discuss philosophy and really reach his evolutionary potential.

All kidding aside, Macho’s baboon-tiger nut connection not only assures us that Kenya’s baboons are eating a healthy diet but also sheds light on the sort of diet the extinct ape known as Paranthropus boisei may have enjoyed. The muscular work of marathon chewing can affect the shape of the jaw somewhat, though this has nothing to do with evolution into a new kind of creature. A variety of ape with the anatomy needed to extract nutrition from the sources in its environment would be well-equipped to survive, though the idea that it survived for million of years is derived only from worldview-based unverifiable assumptions.

The baboon study, however, tells us nothing about the diet of human ancestors.

The baboon study, however, tells us nothing about the diet of human ancestors, cousins or otherwise. I have, in this article, followed the convention of calling Paranthropus boisei “Nutcracker Man,” as if this extinct ape really was an advanced evolutionary product on its way to human-hood before being side-tracked by extinction. Despite all the cute nicknames, however, animals like Lucy and Ardi and Nutcracker Man are nothing more than extinct apes.

Nothing in experimental biology has ever demonstrated any animal evolving into a more complex new kind of animal. Nothing about walking upright on two legs has been shown to increase the genetic information that directs the formation of an ape’s brain to produce a more human one. No amount of good nutrition can fuel the never-observed changes needed for molecules-to-man evolution to take place. Humans did not evolve—and could not have evolved—from ape-like ancestors.

Thanks to Macho’s research, we have a reasonably supported picture of a now-extinct ape scrabbling in the dirt beneath sedges and chewing for hours on the tiger nuts he found there. This image of the untestable past fits the scientific facts modeled by Kenyan baboons in the observable present. But the image of those same extinct apes or others similar to them evolving into more complex intelligent human-like beings is ludicrous fiction, not supportable by the observable facts of biology, and at odds with the historical account of our origins provided by our Creator in the Bible.

You can read more about the biology of humanity’s historical origins in “Did We All Come from Adam and Eve?” Then be sure to learn why our identity as the descendants of Adam actually matters in ““The Search for the Historical Adam” and Population Genomics” and “The Importance of an Historical Adam.”6