100 Million Years of Food (9 page)

It's unlikely that a single thrown hand-axe could have killed a mammal. However, prior to the invention of bows and arrows and other projectile weapons, if
Homo erectus
were to make a throwing weapon out of stone, it could either be shaped like a baseball, which could be thrown fast and far but would bounce off the hide or skull of a large mammal, or it could have a cutting edge, in which case something like an Acheulean hand-axe would have been the logical design, the closest a stone tool creator could ever get to working basalt or chert into a decent throwing knife. In all likelihood, it still wouldn't kill, but with skill and luck it could open a wound, and the prey might be pursued afterward. If throwing weapons were used around a body of water, such as existed near Olorgesailie, then a stockpile would have been necessary to replace the lost arsenal. Carrying them in a bag like a sack of quivers, a
Homo erectus
hunter could have had at least a few chances to bring down some game or to inflict a serious wound on an enemy. It's hard for us today to imagine how a walking ape hurtling a sharpened rock could bring down an animal, but perhaps a thousand years from now, it will be equally hard for people to imagine how a baseball could be thrown at a hundred miles an hour into a catcher's mitt sixty feet away. Whichever hand-axe theory anthropologists support, they all agree that the skill and imagination required to make these objects is wondrous to contemplate and helps to demolish the stereotype of a brutish hunter-gatherer shuffling about in the wilds, devoid of creativity and refinement.

One time, while studying anthropology in Los Angeles, I found myself with a few days off. Not having made many friends in L.A. by that point, I packed up a tent, a stove, some tins of octopus and sardines, and a couple of gallons of water in plastic jugs and piled everything into the hatchback of my '92 Ford Escort. During a recent teaching session, an archaeology student had demonstrated the art of knapping, or shaping a stone tool—an Acheulean hand-axe, in this case. The exercise seemed dangerous but fun, so I headed off to the desert to see if I could bang out some hand-axe replicas myself. I set up camp in a valley without a soul in sight. Overlooking my campsite was a long-abandoned dwelling high on top of a hill. I hiked up the boulder slope and explored the foundation ruins, wondering what kind of man would choose to lead his family out here and how long it took before the wife packed up her suitcases and left her misfit ex-husband alone to ponder life in this desolate spot. The landscape was painted in ochre and sandstone, peppered with forlorn Joshua trees, yucca, and low thorny bushes, the shadows distinct and long. I picked up different kinds of rocks and chipped away at them, and eventually, after cutting my hands, succeeded in creating a crude hand-axe, with none of the smooth curves on the Acheulean hand-axes but of approximately the right proportions.

There were a few skinny gray hares hopping about. I picked up my hand-axe and stalked them, trying to ding one with the weapon. I could not even get within a few feet of hitting one because the hares were too fast and wary and my aim was terrible. Hungry, discouraged, and dusty with all the running about, I gave up and started back to camp. Perhaps that night I would crack open a tin of sardines in tomato sauce and gaze at the stars; perhaps, before the sun disappeared altogether, I would have time to carve my initials into the hand-axe—or someone else's initials? I could spend the night under the blazing stars pondering which lady-friend would be most impressed with the symmetry of my crude handiwork. Who knows, if the fellow up on the hill had been a better knapper, he might have been able to woo another wife for company in this lonely desert.

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The Paleo diet, often slammed by mainstream nutritionists as one of the worst contemporary diet plans, takes its name from the interval when stone tools first appear in the archaeological record, more than 2 million years ago. Similar to the Atkins/low-carb diet, it embraces meat and fat. The standard argument is that humans evolved to eat meat, fish, vegetables, and occasionally fruit and tubers, and any dietary innovations that came afterward, like milk, wheat, potatoes, corn, and beans, were too recent for evolution to have caught up and modified our genes and digestive systems. (Although people who believe in human evolution and those who subscribe to literal interpretations of the Bible have generally quarreled in the past, some of them now find themselves strange bedfellows in their unity concerning the virtues of meat.) The Paleo diet looks and sounds evolutionary, but some paleoanthropologists dismiss it as overly simplistic, a caricature of actual evidence—like dividing the world into good guys and bad guys.

Supporters of the Paleo diet argue that it was not just the Inuit who could thrive on a meat-rich diet. They point to Vilhjalmur Stefansson, a second-generation Icelandic American anthropologist, writer, and Arctic explorer in the beginning of the twentieth century, as one example. Stefansson and one of his Danish expedition mates, Karsten Andersen, thrived on boiled mutton and mutton broth for a year, thereby settling a long-standing debate about whether it was possible for humans to live on meat alone.
19
All the meat eating on his Arctic expeditions didn't seem to adversely affect Stefansson's health. He was romantically involved with the American novelist Fannie Hurst, had a child with an Inuit woman, and finally settled down with a twenty-eight-year-old woman when he was sixty-two. He passed away from a stroke at the age of eighty-two.

Recent genetic studies offer potential backing for Paleo and low-carb diets in combating obesity. It turns out that people vary in the number of genes required to produce salivary amylase, an enzyme used to break down starches in the mouth. Most people have around five copies of this gene; the overall range is between two and thirteen. People who have fewer copies of this gene are more likely to be obese. In theory, this means that eating fewer starches should help these people lose weight, but this depends critically on what people eat instead of starches. Substituting fat for starch increases the palatability of food, which could make people eat more; substituting animal protein for starch may trigger similar problems. Substituting plant protein for starch might seem like a good idea, but then too much protein leads to protein intoxication and lack of palatability, which will tempt dieters to binge on foods that taste good, like starches, fat, and meat, and we're back to square one. In the future, it might be possible to take pills that mimic the effect of salivary amylase. In the meantime, as we will discuss later in the book, the only measure so far that is effective in reducing weight is to increase moderate physical activity, principally walking, and to decrease sitting time.
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Committing to carb avoidance means calories have to come from somewhere other than starches or protein; humans can only tolerate protein consumption comprising a maximum of about 40 percent of total caloric intake, due to the toxicity of nitrogen compounds stemming from protein digestion. (During his yearlong meat-only experiment, Stefansson insisted that he be allowed to eat meat with a lot of fat on it, to counteract the effects of eating a lot of protein.) This leaves saturated fat as a major source of Paleo energy, because there's only so much olive, avocado, or fish oil a person would want to consume. Rather than starve, some Paleo enthusiasts plow into fatty meat. The problem is the supermarket version of Paleolithic diets: A day's worth of stalking wild game and snacking on bugs is replaced by beef steaks, sausages, pork chops, and fried eggs, fatty rich fare beyond the dreams of most hunter-gatherers. Few if any nutritionists would object to a historical hunter-gatherer diet, whether it be based on deer or nuts and grasses.

Paleo and low-carb enthusiasts, however, are apt to characterize these kinds of criticisms as nitpicking, countering with a legitimate observation: They simply feel and perform better—at the office, in the bedroom, at the gym—eating a lot of meat, fat, and cholesterol; so take that, you lousy politically correct pudgy carb-eaters. As it turns out, there is some scientific justification behind the connection between meat, mood, and sex. One key aspect in this connection is cholesterol. Our livers and intestines synthesize most of our cholesterol, but in Western diets, 12 percent to 15 percent of serum cholesterol comes from dietary sources such as eggs, oysters, whole milk, and meat.
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Humans use cholesterol in a wide array of body tissues and to manufacture hormones like cortisol, estrogen, and testosterone. Women have far lower levels of testosterone than men, but the hormone is still critical for sex drive in women. Flagging libido can be treated using testosterone patches, creams, or injections, but pundits throughout history have advised using cholesterol-rich foods to spice up your love life. Brains, crustaceans, mollusks, cuttlefish, octopus, and oysters were used as aphrodisiacs in ancient Greece, imperial Rome, and medieval Europe.
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Oysters were potent symbols of eroticism in seventeenth-century Flemish allegorical paintings.
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T. S. Eliot made reference to the association between oysters and lust in his gritty poem “The Love Song of J. Alfred Prufrock”:

Of restless nights in one-night cheap hotels

And sawdust restaurants with oyster-shells

Writing in the eleventh century, Constantinus Africanus described the following cholesterol-rich aphrodisiac:

Another medicine which is taken before intercourse because it is amazingly stimulating: take the brains of thirty male sparrows and steep them for a very long time in a glass pot; take an equal amount of the grease surrounding the kidneys of a freshly-killed billy-goat, dissolve it on the fire, add the brains and as much honey as needed, mix it in the dish and cook until it becomes hard; make it into pills like filberts and give one before intercourse.
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The sexual powers of lobster were acknowledged in a poem written in 1713:

The Lusty Food helps Female Neighbours,

Promotes their Husband's, and their Labours;

And in return much Work supplies

For that Bright Midwife of the Skies.

Lobster with Cavear in fit Places,

Gives won'drous Help in barren Cases;

It warms the chiller Veins, and proves

A kind Incentive to our Loves;

It is a Philter, and High Diet,

That lets no Lady sleep in Quiet.
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Consumption of cholesterol and fats of all kinds (except trans fats, which are found mostly in industrially produced foods and red meats) also props up high-density lipoprotein (HDL) cholesterol levels.
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When HDL cholesterol tanks, men are at greater risk of impotence and erectile dysfunction. Nuts, employed as aphrodisiacs by ancient Greeks, also boost HDL cholesterol levels.
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Widely used cholesterol-lowering statin drugs inadvertently suppress testosterone and increase the risks of erectile dysfunction and diminished libido.
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People with low cholesterol levels are also more likely to be irritable or depressed, get suspended or expelled from school, and perish from violent deaths, including accidents, homicides, and suicide.
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Thus there is considerable scientific evidence that eating generous portions of animal foods is likely to put one in a good mood. On the other hand, eating a lot of meat likely predisposes girls to reach sexual maturity at an earlier age and thereby die sooner as well.
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By the cold calculus of natural selection, that's an acceptable compromise, because it would have meant more babies starting out life earlier. Evolution doesn't necessarily favor animals that live longer; all else being equal, evolution favors animals that have more compact life spans, reproducing and dying sooner, for the same reason that a nimble company that produces stylish but cheap gadgets or clothing can outcompete brands that take longer to adapt and reach the market.

This is the “life-history” view of diet and health: More robust health at an early age comes at the expense of longevity. Prostate cancer also has the hallmarks of a life-history disease. The nutrients that tend to put men at higher risk of getting prostate cancer—calcium, zinc, fat—were scarce in ancestral diets, but a diet rich in them, along with higher calorie intake in general, would make a man taller, more buff, and richer in sperm count, and thus a stronger contender in the mating market.
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In other words, the robustness of meat-eaters and the long lives of meat-abstainers are two sides of the same biological coin. It all depends on how you define
healthy.
Does healthy mean being in a great mood and being fertile and stronger at a younger age, or does healthy mean delaying cancer for a couple of years and hanging out with your great-grandchildren? This is a question that each of us—and especially parents—needs to carefully consider when thinking about the Paleo diet and other meat-heavy regimes.

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Ah, there's someone else knocking on the door.… Everyone, please make room, and I mean a lot of room, because I'd like to introduce a final guest at history's meat-eating table: your cannibal cousin.

The evidence for cannibalism is omnipresent throughout the animal kingdom. Insects, spiders, leeches, octopus, fish, salamanders, frogs, and birds do it; so do mammals ranging from mice to polar bears, gorillas, and chimpanzees; so did our hominin ancestors, in places like Spain and Iran and China, judging from cut-marks on bones, telltale traces in feces, and cooking residues; and so did modern humans, all around the world. Like most animal cannibals, hominins usually ate infants and juveniles because they put up less of a fight, though fallen enemies were fine dining (or treated like garbage) and deceased relatives were honored.
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Everything was gobbled, including muscle, marrow, and brain, except perhaps the gallbladder, reported to be bitter.
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The cannibalistic habit was so widespread that it may have even left a genetic signature in our DNA, a gene variant that confers resistance to a disease from eating prion-infected brains.
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When viewed in broad perspective, what's most notable about human cannibalism is how squeamish we've become about it.
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As we'll discuss in the next chapter, in part that's because humans view flesh as more than just food—it's a cultural hydra writhing with taboos and scandal.