Top 5 Animal Behaviour Experiments That Live In My Mind Rent-Free
And now they live in yours, too
I worked in animal research – specifically behavioural research - for around 5 years, and I would hardly call the experience particularly interesting. My hands were tied with miles of red tape, and everything I did needed to be approved by a thousand people on every level, all the way from my supervisor to the Home Office (UK government body).
This isn’t to say that I think I was unfairly stifled, I strongly believe in the legal and ethical framework within which my study existed, and I’m proud that my work met these standards.
However, not every time nor place has the same standards. Or even good ones.
Historically, animal behavioural experimentation was often carried out with a very laissez-faire attitude, where welfare wasn’t any kind of consideration.
Globally, different countries set their own expectations on ethics and good practice. While I won’t name names, saying “Oh, you can do anything over there” is a common criticism of academic papers.
From my time as both a student and researcher, especially working in animal behaviour, I have a few extraordinary cases burned permanently in my brain.
Here are my top 5 animal behaviour experiments that live in my mind rent-free.
Warning: Some of these are pretty grim.
1 & 2: Cloth Mother and The Pit of Despair
Two studies, inextricably linked.
A deeply controversial (and in my opinion, insane) psychologist named Harry Harlow used rhesus macaques to study learning and cognition in the 1950s and 60s.
To carry out his studies, he needed infant macaques. Usually, infants are with their mothers, but it was far more convenient to Harlow to have these infants separated from their mothers in a “nursery” - to their developmental detriment.
Seeing the nursery-reared macaques gave Harlow some ideas. How far could he push these infant macaques? How would they react to different stresses?
First, we have the Cloth and Wire mothers. Harlow noticed his nursery-reared macaques were behaviourally divergent from the normal mother-reared ones, and would cling to their cloth nappies. This gave him an idea.
Harlow wanted to see what an infant macaque would favour – a soft and fluffy cloth mother doll, that provided no food, or a cold and uncomfortable mother doll made only from wood and wire, which did provide food from a bottle.
He found the macaques ubiquitously favoured the cloth mother, clinging to it most of the time, and only visiting the wire mother when they needed food.
This postulated that sustenance is not the source of the mother-child bond, and that it is more likely to be comfort and contact.
Not satisfied, Harlow wondered what would happen to an infant macaque who had nothing. No real, cloth, or even wire mother. Just complete isolation, in an apparatus he called “The Pit of Despair”.
Infant macaques were isolated in small chambers at 3 months of age, after bonding with their mothers. These chambers consisted of an upside-down metal pyramid, where the macaque would be forced to sit at the bottom and be unable to move or climb the walls.
Harlow used these “pits”, amongst other kinds of isolating apparatus, to keep infant macaques isolated for either 3 months, 6 months, or 1 year.
All became deeply emotionally disturbed, with some year-deprived macaques even starving themselves to death.
It was discussed by many that Harlow’s experiments were “torture”, and likely a sadistic response to the grief of losing his wife. One researcher even publicly commented that Harlow’s studies were essentially useless.
I mean, what exactly did we learn from these experiments? That babies kept away from their mothers and in total isolation developed into disturbed adults?
Deeply informative.
3: Dolphin House
I remember exactly when I learned about this experiment.
I was living in London, studying for my undergraduate degree. I was chilling on my bed when one of my flatmates burst into my room.
“We have to watch this documentary, a scientist wanks off a dolphin”.
We went room to room gathering flatmates, and we all crowded around the tiny TV in the living room.
Yes, a scientist wanks off a dolphin.
Funded by NASA, this 1960s study led by John and Mary Lilly wanted to study the language capabilities of bottlenose dolphins, after the Lillys observed dolphins mimicking human-like sounds using their blowholes.
The theory was that with their mimicking, the dolphins were attempting to communicate with us, and would be able to give important non-human insights – even one day earning their own seat in the United Nations (yes, really).
Part of this study involved the “Dolphin House”, where researcher Margaret Lovatt waterproofed and flooded a multi-storey house, allowing her to live alongside a young male dolphin named Peter, while she attempted to teach him to speak.
However, a problem soon emerged. Peter became enamoured with Lovatt, often becoming “excited” while with her, interfering with their lessons.
For the sake of the experiment, Lovatt decided to manually “deal” with his sexual urges herself. Which is...a choice.
After 6 months of Lovatt’s work with Peter, John Lilley grew bored of the experiment, favouring a new direction of injecting dolphins with LSD – something which Lovatt would not allow with Peter.
With that, funding for the Dolphin House was cut off, meaning Lovatt and Peter were forced to part ways. A few weeks later, away from the house and separated from Lovatt, Peter committed suicide by swimming to the bottom of his tank and refusing to surface.
It goes without saying, Peter never learned to speak.
4: Mouse Heaven
The study’s official name was the “Mortality-Inhibiting Environment for Mice”, but everyone called it “Mouse Heaven”.
In 1968, researcher John Calhoun wanted to study the factors of rodent population growth. Architects were developing ideas on how to create better human cities, and Calhoun thought that he could use mice as a model to better understand how a population grows and sustains itself.
Calhoun built a large enclosure (I couldn’t find a consistent report on it’s size, but it was big for a mouse) filled with everything a mouse needed to thrive. An endless supply of food and water, plenty of soft bedding, and many “apartments” linked together with tubes.
However, a utopia doesn’t guarantee peace.
He introduced 8 albino mice into the enclosure, and observed their population growth. The first pups arrived 3.5 months later, and the population doubled every 55 days. Despite the much larger capacity of the enclosure, the population plateaued at around 2000 mice.
In this “mouse heaven”, mice were faced with conditions that they would never find in nature, and their instinctual behaviour could not adapt.
Social hierarchies became impossible to maintain, with “alpha” (breeding) males dominating unnaturally large hoards of lower-ranked males. In the wild, defeated males would move to new areas after being bested by an “alpha”, but instead they were penned-in and unable to leave. The lower-ranked males were then so high in number that “alpha” mice struggled to maintain dominance, and nests with nursing females were often attacked, with juveniles being frequently abandoned and cannibalised.
The juvenile mice from these disturbed and violent nests then grew to be socially malformed themselves. Female mice would completely self-isolate, and males would show no interest in females - preferring to compulsively groom themselves.
This vicious cycle of social deviation breeding further social deviation caused a “behavioural sink”, and within 5 years mouse heaven had no mice remaining.
I’m not sure what this tells us about urban development, but it was the 60s so nobody cared.
5: Rat Park
Here’s a sweeter one to finish with.
In the 1970s, the practice at the time for addition experiments involved rats being placed in bare cages, in isolation, and being offered water or morphine. Weirdly (not) these rats much preferred morphine.
Psychologist Bruce K. Alexander proposed the radical idea that these rats probably preferred morphine because they were bored and lonely.
So, he ran his own experiments where he created “Rat Park”, an enclosure created specifically to maximise a rat’s happiness.
The park was massive, 200x the size of a regular rat cage. It contained multiple mice of both sexes, so the rats were socially and sexually fulfilled, and had brightly coloured balls and running wheels, giving enrichment and entertainment.
Alexander then monitored the morphine consumption of 3 groups of rats, that: lived their whole lives in Rat Park, were moved from bare cages to Rat Park at 65 days of age, or were moved from Rat Park to bare cages at 65 days of age.
He found that rats that began in cages preferred the morphine solution while in the cage, consuming 19x more morphine solution than water.
The Rat Park rats, on the other hand, actually avoided the morphine water, only trying it occasionally.
The rats that first lived in cages and were then later moved to Rat Park kept their significant preference for the morphine water, however when Alexander experimented with the morphine water recipe, he realised that these rats were actually seeking the “sweetness” of the solution, as they lost interest when the sweetener content was lowered.
He then further pushed the boundaries – what about caged rats that had only ever known morphine water, would they still prefer it to plain water after moving to Rat Park?
Nope. They switched to plain water, avoiding the morphine like all the others.
While the subject of addiction and its myriad surrounding factors and causes is still a massive and complex discussion, I think this study deserves a place within it.
It doesn’t take a genius to realise that happy, fulfilled people with rich lives, are probably less likely to turn to an addictive substance to numb the pain.
Behavioural experiments are so interesting to me, in the fact that we are taking animals that are nothing like us – monkeys, dolphins, rodents – and trying to relate them back to our own minds.
It was something we discussed often during my doctoral studies:
“Don’t anthropomorphise!”
It’s no surprise to me that these studies were in the 50s, 60s, and 70s. When I was writing my thesis, you would be surprised how often I was squinting at grainy scans of old paper-papers, because that’s when scientists invented all the behavioural tests (by being curious sociopaths).
I hope this article demonstrates exactly the sort of mindset we should have as researchers – welfare first, science second.
Thanks for this. It wasn't easy to read. But enlightening.