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Letting the rat out of the bag

The cultural influence of John B. Calhoun's rodent experiments

'I look at Gotham my friends and what do I see? Gangs roam the streets attacking at will. Stress related illness, crime, murder. Their society is collapsing around them just like universe 133..'

These words, spoken by the super villain 'The Ratcatcher' to an audience of rats in a 1995 Batman comic, embody a popular suspicion of the metropolis, of the city gone bad.

They also reflect the influence of the research of John B. Calhoun, an animal ecologist who studied the effects of crowding on social animals, such as rats and mice, at the National Institute of Mental Health in the United States.

Calhoun's early research was published in 1962 and went on to become some of the most widely referenced in psychology. It has also had a wider impact on architecture, literature and popular culture.

The 'universe 133' mentioned in the Batman comic is a direct reference to one of Calhoun's specially constructed 'rodent universes' – enclosures where the animals were provided with food, bedding and shelter and allowed to breed. It was a veritable rat – or mouse – paradise. But just like the Garden of Eden, it was not to last.

The one thing that the rats lacked was space. And as the population grew there were soon too many rats for each to have its own territory and this led to an increasing number of fights.

Rat - Understanding animal researchUnable to control the frequency of social contact, the rats became increasingly stressed. Males became aggressive and some formed gangs, attacking females and the young. Mothers neglected their infants, failing to construct proper nests and even abandoning or attacking their pups. One group of males isolated themselves from the community around them and became exclusively homosexual. Cannibalism began –  first of the abandoned young, then of the victims of violence.

Calhoun commented that the natural behaviours of his rats were so disrupted that the animals had 'stopped being rats.' And the change was permanent. Even as an infant mortality rate as high as 96 per cent sent population numbers plummeting, the rodents had lost the ability to live harmoniously together. He called this phenomenon 'a behavioural sink.'

The macabre spectacle of crowded psychopathological rats and the easy comparisons with human life in the densely populated inner cities ensured that the experiments were quickly adopted as 'scientific evidence' of social decay.

It is this transmission and morphing of Calhoun's research that interests two researchers from LSE's Economic History Department. As part of a project looking at "how facts travel", Drs Edmund Ramsden and Jon Adams have charted Calhoun's influence across academic disciplines as well his broader cultural impact.

'Calhoun's research goes every where,' explains Dr Ramsden. 'It picks up common themes in the US and Britain in the sixties and seventies concerning the breakdown of urban environments and the collapse of civilisation.'

For example, the 1964 brutal murder and sexual assault of Kitty Genovese in Queens, New York shocked a generation. Thirty-eight people heard the drawn out attack on the barmaid and not a single person had contacted the police or intervened.

Dr Adams says: 'It's not so much that Calhoun provides a comprehensive explanation of what happened but people were very happy to make those connections. They turn to his research to help explain this otherwise inexplicable and terrible event.'

Commentators also used Calhoun to try to explain the serious urban riots of the sixties and the problems of the big housing projects in the United States. It was easy to see both as the product of the crowd – too many people in too small a space caused aggression, deviance and violence as well as physical health problems.

Indeed Calhoun was complicit in encouraging the application of his research to human behaviour. He deliberately designed his rat pens to imitate crowded tower blocks with claustrophobic stair wells and passage ways where the rats had to squeeze past each other.

The idea that a badly designed building could result in real stress began to have currency in the architectural community. Psychologists interested in building design suggested rethinking office spaces. Partitions were used to break up the open-plan layout to give people privacy, their own 'territory' – precisely what Calhoun's rats didn't have.

'Calhoun's "rat cities" provided principles that can and, to some extent, have been applied at the institutional level –   in the redesign of schools, hospitals and dormitories –   to create environments where people would be able to work, live and interact with less stress,' says Dr Adams.

The period following the publication of the rat research also saw a rush of popular books and films with an apocalyptic view of a future crippled by over population. In Anthony Burgess's The Wanting Seed, for example, massive overpopulation results in ultra-violence, compulsory homosexuality and isolation.

The writers of Judge Dredd, the flagship character of the British comic book 2000AD, recall being aware of Calhoun's work. Dredd brutally polices massively overcrowded 'Mega-cities' – urban environments which had exceeded what Calhoun called the 'megacrisis', the point at which the problems of overcrowding became irresolvable. 

These popular representations of Calhoun's work emphasised the pessimistic and grotesque, ignoring the fact that not all the deviations seen in the rats had been wholly negative. Some of the rats had actually responded to the stress of overpopulation with acts of ingenuity. This led Calhoun to believe that creative responses to stress would be necessary for humankind to adapt to the new world of the Megalopolis and was frustrated that this message was not widely picked up on.

'Calhoun writes in a way that is not traditionally scientific,' says Dr Ramsden.' He uses references from literature, such as George Orwell's books, that are construed to pick up on our concerns about the city. He wants people to get the message and be frightened because he thinks then they will act. However, he is perhaps naïve because he doesn't expect to be associated with such a wholly pessimistic outlook. Calhoun's research slips out of his control and he is dismayed because he sees himself not just diagnosing the problem of the American city but also as trying to look for a solution.'


Useful links

Escaping the Laboratory: the rodent experiments of John B. Calhoun and their cultural influence by Edmund Ramsden and Jon Adams, Journal of social history