Genes, environments & behaviors
Our large brains are surely at the center of our humanity. But it is equally certain that few organs are the subject of more misinformation in scientific and public discourse–especially in the widespread notion that most behaviors controlled by our marvelous brain are somehow programmed into it genetically. A typical treatment in the popular press is this overexcited claim by columnist Nicholas Wade in the New York Times: “When . . . [the human genome] . . . is fully translated, it will prove the ultimate thriller–the indisputable guide to the graces and horrors of human nature, the creations and cruelties of the human mind, the unbearable light and darkness of being.”1
Wade may get a pass for being a journalist, but some scientists are equally confused. Molecular biologist Dean Hamer wrote: “People are different because they have different genes that created different brains that formed different personalities,” and “[u]nderstanding the genetic roots of personality will help you ‘find yourself’ and relate better to others.” As distinguished a neurobiologist as Michael Gazzaniga is guilty of the misleading claim that “all behavioral traits are heritable”;2 and molecular evolutionists Roderick Page and Edward Holmes have asserted that “genes control 62% of our cognitive ability.”3 In fact, an entire neo-field labeled evolutionary psychology has sprung up based on the misconception that genes are somehow determining our everyday behavior and our personalities. It is a field that believes there are genetic evolutionary answers to such questions as why a man driving an expensive car is more attractive than one driving a cheap car.4
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Endnotes
- 1The authors thank Richard Lewontin, Deborah Rogers, Robert Sapolsky, and Michael Soulé for their comments on earlier versions of the manuscript. N. Wade, “Ideas and Trends: The Story of Us; The Other Secrets of the Genome,” New York Times, February 18, 2001, sec. 4, 3.
- 2M. S. Gazzaniga, The Ethical Brain (New York: Dana Press, 2005), 44.
- 3R. D. M. Page and E. C. Holmes, Molecular Evolution: A Phylogenetic Approach (Oxford: Blackwell, 1998), 119.
- 4D. M. Buss, The Evolution of Human Desire (New York: BasicBooks, 1994), 99–100.