Yummy-yumping Yuppies are a recent phenomenon. In the long history of humankind, few peoples have had such opportunities to choose what they want to eat. Rather, they ate what they could.
How much of anyone's diet comes from animal protein, and how much from vegetables, varies enormously even today. We are just beginning to understand the connection between what we eat and how we live, how long we live, and the nature and division of labor in human societies.
At a symposium cosponsored by the L. S. B. Leakey Foundation last week at the Southwest Museum, speakers focused on the evolution of hunter-gatherers in the new world. They reminded us that \o7 homo sapiens \f7 have lived in the Americas for at least 20,000, and perhaps as long as 40,000, years. But the study of human evolution is scarcely a hundred years old.
Yet, as Lewis R. Binford from the University of New Mexico at Albuquerque pointed out, that is time enough for myths to have grown up about the evolution of human societies. Primary among these is the idea that hunter-gatherering is a primitive stage of human development that "evolves" into something more "advanced" at the magic moment when some genius figures out that planting a seed works. From this, the story goes, came agriculture and great urban civilizations. Playing devil's advocate, one could also argue that agriculture encouraged human population explosions that precipitated expansive empires, slavery, war and the subjugation of women.
Binford has compared his own studies of modern Eskimo hunter-gatherers with the archaelogical data from Pleistocene sites and reached different conclusions. There is enormous variability in the geographical areas in which different nomadic groups live, and there is corresponding variation in the size of their populations. For peoples in some latitudes, agriculture is not the best way to get food.
Agriculture, he points out, is one strategy of accommodating more people into the landscape. Another option is mobility. Comparing hunter-gatherer societies in the tropics to those in the arctic and desert regions, Binford shows graphically that the equilibrium of human population systems is a function of the amount of rainfall in an area and the length of the growing season.
Kristen Hawkes of the University of Utah has worked among the Ache, hunter-gathers in tropical eastern Paraguay. In contrast to the Eskimo, who hunt and store their food, the Ache, when she first met them, got most of their protein from gathering about 40 species of plants. However the introduction of the gun to replace the bow and arrow raised the proportion of monkey meat in their diet from 25% to 70%.
Hunting provides the most protein most efficiently, she argues. And when the Ache got guns, the proportion of all meat in their diet rose from 18% to 89%. This is more than in any other primate's diet, she points out. That is, when given the opportunity, human beings prefer to eat meat because it is richer in protein and far less labor-intensive to get. Humans eat more animal food than other primates, even when they hunt by hand. Moreover, she argues, using examples from some studies of baboons and chimpanzees as well as her own research among the Ache, hunting seems to encourage sharing. The hunter does not take more food for himself and his family but distributes it equally.
Animal protein may indeed be necessary to maintain a nomadic way of life. Yet urban man faces different challenges. Other primates live happily as vegetarians and there is evidence that diets low in animal protein are healthy for people, too. The role of hunting, and the animal food that it provided in terms of our early evolution, ought not to be confused with the question of diet in today's high-density urban environment. Nor ought modern hunter-gathers like Eskimos be confused with their ancestors. No human society today is entirely isolated from the larger industrial world, and even Eskimos have the option of becoming vegetarians.