This week we take a dive into the work of ethnologist John B. Calhoun and the very unexpected results of his experiments, and most importantly what this means to us personally. It's a big-picture look, but that's what we do here, so enjoy!
Here is the full script of the episode:
Hello and welcome back to the Speaking of Cults podcast. I am your host, Chris Shelton. Usually on my podcast we circle around obvious cultic behavior and interviews with former cult members but lately we’ve been taking some deeper looks at aspects of society and our lives that may not have obvious cult connections but which in fact help us understand the cult problem in entirely different ways. Good science sheds light on all sorts of things that it may or may not have been intended for, just as common sense can sometimes help us make decisions in uncommon situations. So today we’re exploring an experiment that has intrigued scientists, philosophers, and futurists for decades: John B. Calhoun’s Universe 25.
Given that it was called Universe 25, we know there were actually many studies conducted over many years leading up to this one. They were conducted with mice but were more than just an investigation into animal behavior. Universe 25 and its results served as a chilling allegory for human societal collapse. So who was John B. Calhoun? What exactly was the Universe 25 experiment? And what lessons can we draw from it today? Let’s dive in.
To understand the Universe 25 experiment, we first need to know a bit about the man behind it. John B. Calhoun was an American ethologist and behavioral researcher who focused on the effects of population density on behavior. Born in 1917, Calhoun earned his Ph.D. in zoology from Northwestern University. Over his career, he became known for his pioneering work in the study of animal populations, and his insights have influenced fields ranging from urban planning to psychology.
Calhoun’s interest in population density began in the 1940s when he worked at the National Institute of Mental Health. He was fascinated by the idea that overpopulation could significantly alter the social and behavioral dynamics of a species. This led him to design a series of experiments with rodents, culminating in his most famous study: Universe 25.
The Universe 25 experiment was conducted in 1972 and was intended to simulate the effects of overpopulation on behavior. Calhoun created a so-called "mouse utopia"—a sealed enclosure that provided an ideal environment for mice. The habitat was meticulously designed: it was clean, climate-controlled, and stocked with unlimited food and water. There were no predators, and disease was minimized. The space was divided into small chambers connected by ramps and tunnels, providing ample room for the mice to explore.
Calhoun started with just four pairs of mice. These founding members thrived in their new environment, and their population began to grow exponentially. By Day 315, the population peaked at around 2,200 mice. But then, something strange happened.
Despite the abundance of resources, social structures began to break down. Calhoun observed a series of alarming behavioral changes, which he categorized into distinct phases. Let’s examine these phases in detail.
During the early days of the experiment, in what you might consider Phase 1 of the experiment, the mice were in what Calhoun called the "strive phase." The population grew rapidly as the original pairs of mice reproduced. Social hierarchies naturally formed, and the mice engaged in typical behaviors such as nesting, grooming, and rearing their young. During this phase, the mice’s behavior was relatively normal, and their environment appeared harmonious.
As the population grew, it entered Phase 2, the "exploit phase." Competition for space and social status began to emerge. Dominant males became more aggressive, often fighting to secure territories and mating rights. Subordinate males, unable to compete, became increasingly stressed and began to withdraw from social activities. At the same time, the growing population placed a strain on the available nesting areas, and the quality of maternal care began to decline. Instances of infanticide and neglect of offspring started to surface, foreshadowing the societal breakdown to come.
Remember, the males had no external predation or threat to protect themselves or the group from. So where were those instincts directed? Towards their fellow mice, of course, the only other living things they could interact with. And so we see factioning of the population into various groupings which arise from this internalized conflict.
By the time the population peaked, Phase 3 or the "equilibrium phase" began. This was the most critical stage, marked by what Calhoun termed the "behavioral sink." The enclosure’s social dynamics collapsed. Aggressive males continued to attack others indiscriminately, while some males became what Calhoun described as "social dropouts." These withdrawn males ceased all attempts to mate, engage in conflicts, or establish territories. Female mice, overwhelmed by the crowded conditions and constant stress, abandoned their maternal responsibilities. This led to soaring infant mortality rates.
And this is particularly interesting when you think about what assumptions could be made about how these mice “should” have been behaving. Many would look at the aggressive male behavior as perfectly normal because it’s supposed to result in those dominant males overtaking the reproduction functions and flourishing with more young of their own then anyone else, thereby winning the genetic lottery by passing on their genes and thereby ensuring more mice will come just like them. Yet where does this go? Fewer and fewer mice. This dominant aggressive behavior may intuitively look like the “natural order of things” to many of us humans looking in on this experiment, but if survival of the species is your goal, domination by the most aggressive males of the species is not the way to achieve it.
Getting back to the experiment, finally the population of mice reached Phase 4, the final or what was termed "die-off phase." Reproduction effectively ceased as the mice stopped mating altogether. A group of mice emerged that Calhoun referred to as the "beautiful ones." These individuals were physically pristine because they avoided any interaction that could lead to conflict or injury. They spent their days grooming, eating, and sleeping, completely detached from the social fabric of the community. Despite their appearance, they were emotionally and socially vacant. Over time, the population dwindled, and by Day 600, the once-thriving colony was extinct.
The implications of the Universe 25 experiment were both fascinating and deeply unsettling. Calhoun concluded that social structures and meaningful interactions are as vital to survival as physical resources. He argued that overpopulation and the resultant stress could lead to societal collapse, even in environments with abundant material wealth.
However, Calhoun’s findings were not without controversy. Critics have pointed out that mice and humans have vastly different social structures and capacities for adaptation. Still, the experiment serves as a stark reminder of the psychological and social challenges posed by overcrowding, a topic that remains relevant as urban populations grow.
So, what can we learn from Universe 25? I believe quite a bit. We need to be careful about drawing exact parallels between mice and humans because we are not the same things and human cultures are exponentially more complicated than what mice get up to. However, this experiment does tell us a great deal about the nature of life under specific, utopian conditions. And given the fact that almost every cult leader who has ever lived has centered his or her dogma around the idea of a utopian future, it is pretty interesting to see that life doesn’t thrive in utopia. It dies.
Our parents and their parents before them told us a lot of things and made us think that how things are now is the so-called “natural order of things.” That’s not really true. Society and how things are structured and even how we interact and think about each other change radically from one society to another, from one time period to another. Our forefathers lived lives radically different from the way we live ours. And perhaps in the progress of modern technology, we have innovated ourselves away from the most important things about being a living human being: having a purpose and meaning to our lives and fostering meaningful social interactions. We have utterly failed to manage population density in a way that supports not only our mental health but our society’s future. This has led to worsening mental health conditions, higher levels of stress and anxiety and therefore higher levels of groupthink, divisiveness and us vs them thinking. These issues have become global in impact since our world has become increasingly interconnected and urbanized.
There is no question that this information can be used to encourage a kind of nihilistic attitude about today’s culture wars and ideological divides. But let’s remember that cults are a natural outgrowth of a stressful environment and on an individual basis, it doesn’t help us to abandon hope or lose sight of an optimistic future.
From my perspective, Calhoun’s work is almost scientific proof that our role as human beings go beyond existing or having fun or being happy. We don’t exist just to be selfish, isolated islands of emotional ups and downs. We are tribe-based, pack animals if you will. It’s built-in to us that we need a social network and hierarchy and we need to have a place in that hierarchy that makes sense to us, that we can do meaningful work in and that we can therefore feel good about. Lacking that, all sorts of problems ensue.
Coming down to earth and to us as individuals, having a purpose and function in society is everything. Having value is not something society is imposing on a person - it’s the exchange that person needs to feel part of society in the first place! It goes back to the basic equation of life itself - tit-for-tat. Ironic given the Hubbard emphasis on exchange but that’s really just him using this most basic of life’s characteristics to twist it for his own ends.
Behavior sink makes perfect sense - if there are no challenges, why be alive at all? It presents a practical answer to why we are even alive in the first place - it’s not just “to live” or “to exist” - we as life units need more than that. I believe this is perhaps one of the most basic emotional needs we have and this is why cult leaders can and do hook people - especially young people - with the idea of giving them a purpose or drive or meaningful existence beyond the “banality of common society” or whatever other way they talk about it.
There is this old phrase out of mental health about being a ‘well adjusted’ human being. At one point, all of people’s psychological troubles were explained as a ‘chemical imbalance’ with the ridiculously simplistic idea that a pill or a breathing technique was going to cure everything that is wrong with you. Unfortunately, living a balanced life between yourself and society requires a little more work than that. Finding that balance is finding that place where you can be the person you know you are, but still coexist with the people who constantly come in and out of your life and which represent our society. We can’t just tell ourselves we are part of this picture and that we matter. We have to go do things that do matter and that make us part of the picture. That’s what it means for each of us to ‘do our part.’ I don’t mean going out and making a mark or being some influencer or even having to talk to people all that much. It’s about exchange and contribution and playing nice with others despite all the great sounding but incredibly destructive ideas that we don’t matter, that what we do doesn’t matter and that individually our lives mean nothing. I mean, if that’s true then how come we love all those time travel stories where we think that if someone goes back in time and changes even one little thing, it could end up having catastrophic consequences on the future? I’ll just say right now that every little thing you do does matter, and not just to you. And I hope at least this is some food for thought for you.
So that’s all for today’s episode of Speaking of Cults. I hope you enjoyed this deep dive into the fascinating and thought-provoking Universe 25 experiment. If you found this episode interesting, please subscribe, leave a review, and share it with your friends. Have thoughts on today’s topic? Drop us a message on our social media. See you next week.
