Dr. Calhoun’s Mousery: The Strange Tale of a Celebrated Scientist, a Rodent Dystopia, and the Future of Humanity

This stimulating scientific history from Dugatkin (How to Tame a Fox and Build a Dog), a biology professor at the University of Louisville, recaps psychologist John B. Calhoun’s yearslong experiments on mice and rats in the 1960s and ’70s. Calhoun’s most famous experiments placed a modest number of rats (often eight) in a “rodent utopia,” an artificial enclosure in which they enjoyed limitless food and water, where he observed how their behavior changed as their number increased. He found that bizarre dysfunctions appeared at high population densities: groups huddled together in crowded “neighborhoods,” even when they had access to comparatively empty enclosure areas; dominance hierarchies in males broke down, leading to increased sexual aggression toward females; and pregnancy rates plummeted while mothers neglected their pups. The findings, Dugatkin notes, were covered breathlessly by the press. Tom Wolfe’s The Pump House Gang cited Calhoun’s rat studies to explain alleged cultural decay in New York City, and biologist Paul Ehrlich discussed them in his 1968 bestseller, The Population Bomb, stirring up public concern about the deleterious effects of human overpopulation. Dugatkin offers colorful accounts of Calhoun’s experiments, and descriptions of the exigencies of the rat-race within them intrigue (rodents shunned upper stories of multifloor nesting structures because they dislike climbing stairs). This fascinates. Photos. (Oct.)