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An astute reader asks, "If your book is about the origins of human sexuality 'before agriculture and writing,' how did you develop your basic thesis? Without written records, what are your theories based on?"
Good question. Below is an excerpt from our up-coming book, where we look at that question.
The short answer is that we need to triangulate. The reader's point is that we're developing theories about social relations in prehistory -- relations that leave no skeletal or other types of archaeological evidence. True enough.
So we study associated bodies of evidence and look for areas where they all intersect. Specifically, we look at primates -- particularly the chimp and bonobo, which are by far the closest to humans. We look at anthropological studies of hunter-gatherer people, whose lives presumably reflect much of what we'd find if we could venture back 50,000 years. We look at human anatomy (see below) and what it tells us about the environment in which the human body evolved (and continues to evolve). And we look at contemporary human psycho-sexuality to see if we can find areas where people's current fantasies, pathologies, and predilections might tell us something about an underlying "design" that still lingers from long ago.
As it turns out, each of these areas is rich in fascinating information that sheds light on the origins of human sexuality.
We hope this begins to answer your question -- or at least whets your appetite for the book!
* * * * *
Everybody has a story to tell. So does every body.
Like any narrative of human life in prehistory, ours rests on two types of evidence: circumstantial and material. We’ve already covered a great deal of circumstantial evidence concerning the probable environment in which Homo sapiens evolved (the EEA) : social systems, economics, diet, relative male/female status, sexual behavior in closely related primates, and so on. Thus far, the only real material evidence we’ve offered has centered on archaeological indications of prehistoric human social life (shelter size and design, prominence of nomadic subsistence, absence of evidence of food-storage in the archaeological record, and so on). But it’s a stretch to base a comprehensive model of human sexual behavior in the Pleistocene on just a few scattered artifacts. The song says, “What goes up must come down,” but unfortunately for archaeology, most of what goes down never comes back up. Social behavior is especially difficult to infer from fragmented bits of bone, flint, and pottery – fragments that represent a tiny fraction of what once existed.
Skepticism is warranted.
Years ago, at a conference in India, the subject of our research came up over dinner. When we explained that we were investigating human sexual behavior in prehistory, the esteemed professor across the table from us scoffed and asked, “So what do you do, close your eyes and dream?” While one should never scoff with a mouthful of pakora, the old coot had a point. His dismissive remark reflects the truism that social behavior doesn’t leave physical artifacts, so any theorizing amounts to nothing but “dreaming.” In fairness to the professor, we’ve since heard similar scoffing at cocktail parties throughout the world.
Famed paleontologist, Stephen J. Gould asked, “How can we possibly know in detail what small bands of hunter-gatherers did in Africa two million years ago? These ancestors left some tools and bones, and paleoanthropologists can make some ingenious inferences from such evidence. But how can we possibly obtain the key information that would be required to show… relations of kinship, social structures and sizes of groups, different activities of males and females…?” Richard Potts, director of the Smithsonian’s Human Origins Program, warns that, “Many characteristics of early human behaviour are…difficult to reconstruct, as no appropriate material evidence is available. Mating patterns and language are obvious examples – social life, words and grammar leave no traces in the fossil record.” But he then goes on to add, almost under his breath, “Questions of social life… may be accessible from studies of ancient environments, or from certain aspects of anatomy and behaviour that leave material evidence.”
Is Potts suggesting that maybe the truism isn’t true, after all? Can we glean important information about the contours of ancient social life – particularly concerning sexual behavior – from present-day human anatomy? As it turns out, we can.
In the next three chapters, we review the anatomical evidence relevant to human sexual evolution. We’ll leave the chemicals (hormones, neurotransmitters) for the following section (Reading the Sexual Mind), because they tend to manifest in behavior. The body gives us plenty to talk about.
Renowned biologist, Richard Dawkins explains that every creature’s body tells a detailed story about the environment in which its progenitors evolved: “If you find an animal’s body, a new species previously unknown to science, a knowledgeable zoologist allowed to examine and dissect its every detail should be able to ‘read’ its body and tell you what kind of environment its ancestors inhabited: desert, rainforest, arctic tundra, temperate woodland or coral reef. The zoologist should also be able to tell you, by reading its teeth and guts, what it fed on…. The animal’s feet, its eyes and other sense organs spell out the way it moved and how it found its food. Its stripes or flashes, its horns, antlers or crests, provide a read-out, for the knowledgeable, of its social and sex life.”
Dawkins leaves delicately unmentioned the fact that the genitalia of this mysterious animal contain far more information about its sex life than its “flashes” or “crests.” As evolutionary psychologist Geoffrey F. Miller notes, “Male sexual ornaments and male genitals are the most useful traits for distinguishing most animal species from closely related members of the same genus.” He goes so far as to say that, “evolutionary innovation seems focused on the details of penis shape.”
Leaving aside for the moment the awkward question of whether even Mother Nature is obsessed with the penis, it’s certainly true that our bodies contain a wealth of information about the sexual behavior of our species over the millennia. This information is encoded in dusty skeletal remains millions of years old as well as in our own pulsing bodies. It’s all right there – and here. We just have to read the hieroglyphics of the sexual body. Far from closing our eyes and dreaming, we need only open them and look closely at ourselves and at each other.
