Universe 25, 1968–1973

UNIVERSE 25: John Calhoun crouches inside his rodent utopia-turned-dystopia that, at its peak, housed roughly 2,200 mice. Calhoun was learning the breakdown of social bonds that happens underneath excessive overcrowding, a phenomenon he termed a “behavioral sink.” Yoichi R. Okamoto, White Home photographer, Public Area

June 22, 1972. John Calhoun stood over the deserted husk of what had as soon as been a thriving metropolis of hundreds. Now, the inhabitants had dwindled to only 122, and shortly, even these inhabitants can be lifeless.

Calhoun wasn’t the survivor of a pure catastrophe or nuclear meltdown; fairly, he was a researcher on the Nationwide Institute of Psychological Well being conducting an experiment into the results of overcrowding on mouse conduct. The outcomes, laid naked at his toes, had taken years to play out.

In 1968, Calhoun had began the experiment by introducing 4 mouse {couples} right into a specifically designed pen—a veritable rodent Backyard of Eden—with quite a few “flats,” plentiful nesting provides, and limitless meals and water. The one scarce useful resource on this microcosm was bodily area, and Calhoun suspected that it was solely a matter of time earlier than this brought on bother in paradise.

Calhoun had been operating comparable experiments with rodents for many years however had at all times needed to finish them prematurely, mockingly due to laboratory area constraints, says Edmund Ramsden, a science historian at Queen Mary College of London. This iteration, dubbed Universe 25, was the primary crowding experiment he ran to completion.

As he had anticipated, the utopia turned hellish practically a yr in when the inhabitants density started to peak, after which inhabitants development abruptly and dramatically slowed. Animals turned more and more violent, developed irregular sexual behaviors, and started neglecting and even attacking their very own pups. Calhoun termed this breakdown of social order a “behavioral sink.”

Ultimately Universe 25 took one other disturbing flip. Mice born into the chaos couldn’t type regular social bonds or have interaction in advanced social behaviors resembling courtship, mating, and pup-rearing. As a substitute of interacting with their friends, males compulsively groomed themselves; females stopped getting pregnant. Successfully, says Ramsden, they turned “trapped in an childish state of early growth,” even when faraway from Universe 25 and launched to “regular” mice. In the end, the colony died out. “There’s no restoration, and that’s what was so stunning to [Calhoun],” says Ramsden.

Calhoun wasn’t shy about anthropomorphizing his findings, binning rodents into classes resembling “juvenile delinquents” and “social dropouts,” and others seized on these human parallels. Inhabitants development within the Nineteen Seventies was swelling, and movies resembling Soylent Inexperienced tapped into rising fears of overpopulation and concrete violence. In a 2011 article, Ramsden writes that Calhoun’s research have been brandished by others to justify inhabitants management efforts largely focused at poor and marginalized communities.

However Ramsden notes that Calhoun didn’t essentially suppose humanity was doomed. In a few of Calhoun’s different crowding experiments, rodents developed revolutionary tunneling behaviors, whereas in others, including extra rooms allowed the animals to stay within the high-density setting with out being compelled into undesirable contact with others, largely minimizing the detrimental social penalties. In line with Ramsden, Calhoun needed these findings to affect the architectural design of prisons, psychological hospitals, and different buildings susceptible to crowding. Writing in a report abstract in 1979, Calhoun famous that “no single space of mental effort can exert a better affect on human welfare than that contributing to higher design of the constructed setting.”