Back in the 1950s, Dr. John Calhoun of the National Institute of Health in Washington DC performed a unique experiment called the Mouse Utopia Experiment. This later came to be known as Behavioural Sink. The purpose of this experiment was to study not just the population growth but its effects on individual behavior as well. The experiment that was completed over a span of several years and Dr. Calhoun used white mice to study the effect of overpopulation under this experiment.
Dr. Calhoun along with his researchers found that in an environment with limited space but unlimited resources, the population of the animals under study would first explode then peak-out and in the end collapse to extinction. Even after repeating the test a number of times, the same results were observed. The reason for such an outcome was found to be derived from social decay and as the population increased, the social decay only worsened with each new generation. This led to unrest in the environment, which in turn led to sub-replacement fertility. All in all, one can say that nature has a limit in which social animals can interact.
In a 16-cell mouse habitat utopian condition of comfort, nutrition and housing were provided for a potential population of over three thousand mice. Yet, in spite of the ideal condition, the mouse population met with catastrophe. Individuals were kept track of by color markings on their fur. Factors that normally control population growth such as predation by cats or owls were eliminated. The transmissible disease was also controlled. In effect, the mouse universe simulated the present situation of the continually expanding population of humans.
The first hundred days of the experiment marked a phase called strive. Dr. Calhoun termed it as strive because this was basically the period of adjustment. In this phase, mice established their territories and nests were made.
The next period of the Mouse Utopia Experiment lasted about two hundred and fifty days. In this period, the population doubled almost every sixty days. Dr. Calhoun named this phase the exploit period. In this phase, the use of resources became unequal. Although each living unit i.e. mouse, in this case, was identical in structure and opportunities, more food and water were consumed in some areas as compared to the others. With the passage of time as the population increased, most mice linked eating and drinking with the presence of others and thus, crowding developed in some areas.
The third period consisted of three hundred days. This phase was marked with the population of mice leveling off. Hence, this was called the equilibrium period. Dr. Calhoun noticed that because most of the space was socially defined already, the newer generations of young were inhibited. At this time some unusual behavior became noticeable. Excess males strived for acceptance but were rejected and withdrew. Moreover, violence became prevalent and the effects of it became increasingly visible. Certain individuals were targeted repeatedly for attacks. These mice would have badly chewed and scarred tails. Whereas, other mice growing into adulthood exhibited a very different type of behavior. Such mice were termed as ‘the beautiful ones’ by Dr. Calhoun. Their time was solely devoted to eating, grooming, and sleeping. They never involved themselves with others, engaged in mating nor would they fight. All appeared as a beautiful exhibit of the species with keen alert eyes and a healthy well-kept body. However, these mice failed to cope with the very unusual stimuli. This means that though they looked inquisitive, they were in fact very stupid.
The Die Period
The last period of this experiment was called the die phase. This phase led the population into extinction. Although the mouse utopia could accommodate almost three thousand, the population began to decline after just two thousand and two hundred. In the shift from equilibrium to the die phase, each animal became less aware of the associates despite all animals being pushed closer together. Dr. Calhoun concluded that the mice could not effectively deal with the repeated contact of so many individuals. The evidence of violence increased to the point where had had their tails bitten to some degree. Eventually, the entire mice population perished.
Dr. Calhoun’s experiment is a classic example of a typical population and its growth when left unchecked. Research in this area continues under his supervision. Currently, Dr. James bill has taken the basics of the Mouse Utopia Experiment to study social behavior even more closely. Though these studies used animals, the findings of population growth and individual behavior are being closely compared to our own human population. Like all populations that have existed on this planet, many researchers believe that the human race has reached a crucial point in the exploit phase, a point where important decisions must be made, and careful planning implemented if we are to survive. The study of plant and animal populations helps us to make decisions about the future of our human population so that we may maintain our own balance with nature.
Many believe that Mouse Utopia Experiment predicts human extinction in the future with extreme violence and overcrowding turning the social animal into anti-social. However, in true essence it is very hard to compare Mouse Utopia Experiment with the human world due to a number of reasons but mainly because the experiment was performed in a controlled environment thus mitigating all the sources of error. Only the adverse trends in human society can be compared with the behaviors observed through the Mouse Utopia Experiment.
An important point to notice in the mouse utopia experiment is that the limiting factor of this experiment was space. This basically shows that space is one of the most decisive factors in the development of the social behavior of animals including humans. From the experiment, it was observed that as time passed with the lack of space, the mice started to pass on the negative behaviors to the coming generation and this became a chain. This means that population condensation surely comes with a number of adverse consequences. Another article ‘The Power of Choice’ by Quintus Curtius explains a similar study to mouse utopia experiment but it was performed on the people of Easter Island. It tells that when humans first arrived there in almost 900 A.D, the area was covered with trees and could have sustained a high population. Similar to the conditions of mouse utopia experiment, there were no external factors of stress such as predators however, the resources were endless. But with time, the island became overly populated. Quintus explains what befell the Islanders:
“The islanders then began to compete with each other more and more fiercely for an ever-declining volume of natural resources; vendettas multiplied, intertribal warfare flared, and a pall of hostility and fear descended on the island. As the trees vanished, the Islanders were unable to build boats to escape to other islands: they became trapped in their own hell, doomed to fight each other in perpetuity for the last crumbs that the barren land could offer. Eventually, the islanders began to starve, and feed—literally—off each other. As wild meats became unavailable, and escape off the island became impossible, the natural consequences followed. Cannibalism stalked the island, animating its folklore and infecting its archaeological sites. Perhaps the islanders compensated for their misery by focusing more and more on the empty ritual of building and raising statutes, as their means of sustenance melted away.”
One may argue that this behavior would not prevail among humans and thus this couldn’t happen to humans because humans have large bands of land that are still unpopulated, it has to be noted that in the experiment even at the peak population, only half the colony space was being used. The mice had a tendency to overpopulate certain sectors of space, but they did not. Hence, it is not just about space but a limitation on social interactions as well that leads to such behavior. There are natural limitations on the level of social interaction humans can manage on a daily basis, just like with the mice.