Crowded Rat Syndrome
In an earlier thread, I mentioned that I felt that there is increasing factionalization of young men and women into separate, isolated, social enclaves. I have been doing some reading of older scientific literature and thought I might share some of my findings, which are relevant to the above observation.
John B. Calhoun was a man concerned with the increasing human population, and ran a number of experiments from the 1940's through the 1970's, looking at the effect of overpopulation on mice and rats. His most famous experiment was published in 1972--the results of his so called "Universe 25". The set up was sort of a rat apartment block, with256 rooms capable of housing 15 mice each, stacked high and surrounding a courtyard below. Unlimited food and water were provided, so the typical effects of starvation etc were taken out of play--the only limiting factor was space.
The experiment was started with a mere four breeding pairs of mice. After an adjustment period, the mice began to breed--and in those early 'golden days', the mice had numerous litters and feasted on the unlimited food provided them. However, with the population doubling every 55 days, things began to become crowded. After day 315, population growth slowed (with over 600 mice at this time). Because of the overcrowded conditions, normal mouse behavior started to break down--male mice had increasing difficulty defending their territories, reducing their success in attracting females, and also leaving pregnant and nursing females open to attack from marauders. Some frustrated female mice began killing or abandoning their young, or giving up on sexual activity altogether.
A significant proportion of females ended up holing up in the highest mouse apartments, alone. And two new castes of males developed. The first were the "losers", listless bachelors who would huddle together in the courtyard, occasionally erupting in bursts of violence. A small segment of these showed unusually high creativity and innovation (and inspired Mrs. Frisby and the Rats of NIMH). The second group were what Calhoun called the "beautiful ones"--males that spent all of their time grooming and eating, never seeking female attention. The remaining mice became increasingly pansexual, violent, and cannibalistic.
This was the beginning of the end. By day 560, the mouse population peaked at 2,200 mice. Fewer and fewer females gave birth, and few pups survived through to weaning. Mouse society had become segregated into uninterested females and the two types of uninterested males, while the reproductive segment of the population had all but disappeared. The population fell, and fell, but even with less crowded conditions, the mice did not resume normal mouse behaviors.
The breakdown of mouse and rat society was highly reproducible: all of Calhoun's "rodent utopias" became rodent hells. Calhoun strongly believed that this was the path humanity would be heading down, and I think that some current social phenomena reflect his findings.