Robert M. Sapolsky

Behave

The Approach in this Book

I make my living as a combination neurobiologist — someone who studies the brain — and primatologist — someone who studies monkeys and apes. Therefore, this is a book that is rooted in science, specifically biology. And out of that come three key points. First, you can’t begin to understand things like aggression, competition, cooperation, and empathy without biology; I say this for the benefit of a certain breed of social scientist who finds biology to be irrelevant and a bit ideologically suspect when thinking about human social behavior. But just as important, second, you’re just as much up the creek if you rely only on biology; this is said for the benefit of a style of molecular fundamentalist who believes that the social sciences are destined to be consumed by “real” science. And as a third point, by the time you finish this book, you’ll see that it actually makes no sense to distinguish between aspects of a behavior that are “biological” and those that would be described as, say, “psychological” or “cultural.” Utterly intertwined.
Understanding the biology of these human behaviors is obviously important. But unfortunately it is hellishly complicated. 2 Now, if you were interested in the biology of, say, how migrating birds navigate, or in the mating reflex that occurs in female hamsters when they’re ovulating, this would be an easier task. But that’s not what we’re interested in. Instead, it’s human behavior, human social behavior, and in many cases abnormal human social behavior. And it is indeed a mess, a subject involving brain chemistry, hormones, sensory cues, prenatal environment, early experience, genes, both biological and cultural evolution, and ecological pressures, among other things.
How are we supposed to make sense of all these factors in thinking about behavior? We tend to use a certain cognitive strategy when dealing with complex, multifaceted phenomena, in that we break down those separate facets into categories, into buckets of explanation. Suppose there’s a rooster standing next to you, and there’s a chicken across the street. The rooster gives a sexually solicitive gesture that is hot by chicken standards, and she promptly runs over to mate with him (I haven’t a clue if this is how it works, but let’s just suppose). And thus we have a key behavioral biological question — why did the chicken cross the road? And if you’re a psychoneuroendocrinologist, your answer would be “Because circulating estrogen levels in that chicken worked in a certain part of her brain to make her responsive to this male signaling,” and if you’re a bioengineer, the answer would be “Because the long bone in the leg of the chicken forms a fulcrum for her pelvis (or some such thing), allowing her to move forward rapidly,” and if you’re an evolutionary biologist, you’d say, “Because over the course of millions of years, chickens that responded to such gestures at a time that they were fertile left more copies of their genes, and thus this is now an innate behavior in chickens,” and so on, thinking in categories, in differing scientific disciplines of explanation.
The goal of this book is to avoid such categorical thinking. Putting facts into nice cleanly demarcated buckets of explanation has its advantages — for example, it can help you remember facts better. But it can wreak havoc on your ability to think about those facts. This is because the boundaries between different categories are often arbitrary, but once some arbitrary boundary exists, we forget that it is arbitrary and get way too impressed with its importance.