The Origin of Humankind by Richard Leakey

having emerged only with the evolution of modern humans, perhaps 100,000 years ago? To answer these questions, we have to pore over clues in the fossil and archeological records, searching for signs of the hunting and gathering mode of subsistence. We will see in this chapter that theories have shifted in recent years, reflecting a change in the way we view ourselves and our ancestors. Before we see how the evidence of prehistory has been scrutinized, it would be helpful to have a picture in mind of the foraging lifestyle, as we know it from modern hunter-gatherers.
    The combination of hunting meat and gathering plant foods is unique to humans as a systematic subsistence strategy. It is also spectacularly successful, having enabled humanity to thrive in virtually every corner of the globe, with the exception of Antarctica. Vastly different environments were occupied, from steamy rain forests to deserts, from fecund coastal reaches to virtually sterile high plateaus. Diets varied greatly from environment to environment. The Native Americans of the Northwest harvested salmon in prodigious quantities, for example, while the !Kung San of the Kalahari relied on mongongo nuts for much of their protein.
    Yet despite the differences in diet and ecological environment, there were many commonalities in the hunter-gatherer way of life. People lived in small, mobile bands of about twenty-five individuals—a core of adult males and females and their offspring. These bands interacted with others, forming a social and political network linked by customs and language. Numbering typically about five hundred individuals, this network of bands is known as a dialectical tribe. The bands occupied temporary camps, from which they pursued their daily food quest.
    In the majority of surviving hunter-gatherer societies that anthropologists have studied, there is a clear division of labor, with males responsible for hunting and females for gathering plant foods. The camp is a place of intense social interaction, and a place where food is shared; when meat is available, this sharing often involves elaborate ritual, which is governed by strict social rules.
    To Westerners, the eking out of an existence from the natural resources of the environment by means of the simplest of technologies seems a daunting challenge. In reality, it is an extremely efficient mode of subsistence, so that foragers can often collect in three or four hours sufficient food for the day. A major research project of the 1960s and 1970s conducted by a team of Harvard anthropologists showed this to be true of the !Kung San, whose homeland in the Kalahari Desert of Botswana is marginal in the extreme. Hunter-gatherers are attuned to their physical environment in a way that is difficult for the urbanized Western mind to grasp. As a result, they know how to exploit what to modern eyes seem meager resources. The power of their way of life lies in this exploitation of plant and animal resources within a social system that fosters interdependence and cooperation.
    The notion that hunting was important in human evolution has a long history in anthropological thought, going back to Darwin. In his 1871 book The Descent of Man , he suggested that stone weapons were used not only for defense against predators but also for bringing down prey. The adoption of hunting with artificial weapons was part of what made humans human, he argued. Darwin’s image of our ancestors was clearly influenced by his experience while on his five-year voyage on the Beagle . This is how he described his encounter with the people of Tierra del Fuego, at the southern tip of South America:
    There can hardly be any doubt that we are descended from barbarians. The astonishment which I felt on first seeing a party of Fuegans on a wild and broken shore will never be forgotten by me, for the reflection at once rushed into my mind—such were our ancestors. These men were absolutely naked and bedaubed with paint, their long