Biological explanations of violence are much in vogue. Part of the reason is that scientists studying the seat of behavior, the brain, and its genetic underpinnings, have learned a lot in recent years. Tendencies toward violence, they tell us, may reside in our genes or be hard-wired into our brains. Some neuroscientists have mapped brain abnormalities in laboratory animals and human murderers that seem to correlate with aggressive behavior. Others have teased out apparent connections between violent behavior and brain chemistry.
Being scientists, these researchers often try to tone down and qualify the connection between violence and biology. But even a faint message seems to fall on extraordinarily receptive ears. The findings of a team of Dutch and American scientists, for example, were recently exaggerated not only by the lay media but by the technical press as well. The researchers had come across a Dutch family in which, for five generations, the men had been unusually prone to aggressive outbursts, rape, and arson. These men were also found to have a genetic defect that made them deficient in an enzyme that regulates levels of the neurotransmitter serotonin. Han Brunner, a geneticist at University Hospital in Nijmegen, the Netherlands, and a member of the team, cautioned that the results concerned only one family and could not be generalized to the population at large, but the caveat was ignored. Stories everywhere, in both the scientific journals and the general media, spoke of his finding an aggression gene.
There are other examples. In a 464-page assessment of the state of violence research in 1992, the National Research Council devoted only 14 pages to biological explanations. Of those 14, genetics occupied less than two pages. All the same, the New York Times covered the report with the headline study cites role of biological and genetic factors in violence. Indeed, the proliferation of genetic explanations for violence prompted a Time writer to note wryly: Crime thus joins homosexuality, smoking, divorce, schizophrenia, alcoholism, shyness, political liberalism, intelligence, religiosity, cancer, and blue eyes among the many aspects of human life for which it is claimed that biology is destiny.
