We evolved to eat berries rather than bagels, to live in mud huts rather than condos, to sprint barefoot rather than play football—or did we? Are our bodies and brains truly at odds with modern life? Everyone is fond of paleofantasies, stories about how humans lived eons ago, and we use them to explain why many elements of our lives, from the food we eat to the way we raise our children, seem very distant from what nature intended. Many diets and self-help books are predicated on the notion that our behavior and bodies evolved under a certain set of circumstances, from which we deviate to our peril. Implicit in that idea is the assumption that humans in a modern society aren’t evolving any more, that we have somehow freed ourselves from evolution, or at the very least, that evolution always requires so long to act that we can’t expect to have adapted to our current circumstances. But popular theories about how our ancestors lived—and why we should emulate them—are often based on speculation, not scientific evidence, and they reflect a basic misunderstanding about how evolution works. There was never a time when everything about us—our bodies, our minds, and our behavior—was perfectly in synch with the environment. Evolution is continuous, and all organisms alive today, whether chimpanzees, modern-day hunter-gatherers, or bacteria, are all equally evolved. What really matters is the rate of evolution, which is sometimes fast and sometimes slow. Instead of trying to live like cavemen, we need to understand that process.
|Marlene Zuk, Ph.D., is a biologist and writer. She is a professor in the Department of Ecology, Evolution and Behavior at the University of Minnesota, where her research focuses on animal behavior and evolution, mostly using insects as subjects. Dr. Zuk is interested in the ways that people use animal behavior to think about human behavior, and vice versa. She teaches graduate and undergraduate courses on a diversity of topics, including a seminar on “What’s the Alternative to Alternative Medicine?” In addition to publishing numerous scientific articles, Dr. Zuk has written for The New York Times, the Los Angeles Times, the Chronicle for Higher Education, and Natural History magazine. She has published four books for a general audience: Sexual Selections: What We Can and Can’t Learn About Sex From Animals; Riddled With Life: Friendly Worms, Ladybug Sex, and the Parasites That Make Us Who We Are; Sex on Six Legs: Lessons on Life, Love and Language From the Insect World (a New York Times “Editor’s Choice”); and most recently Paleofantasy: What Evolution Really Tells Us About Sex, Diet and the Way We Live. |