How a 1940s US experiment tried, and failed, to create a 'super dog'

In 1940s Maine, a group of scientists built the School for Dogs, a massive facility to breed a "super-dog". Things didn't go as planned.

Humans have been a little bit obsessed with dogs for millennia. In the late 1940s, though, an enormous experiment took that obsession to a level never seen before or since. 

The findings would help close one of the darkest chapters in scientific history. 

Unfolding at a giant, specially built facility on a farm in Maine, US, it involved studying more than 500 puppies – cocker spaniels, beagles, Shetland sheep dogs, basenjis and wire‐haired fox terriers – over 13 years. 

From birth, each puppy's development was recorded in exhaustive detail: its first startle response, its first attempt at consuming solid food, its first playfight with a sibling, its first tail wag. At five weeks old, the puppies began a battery of tests assessing everything from intelligence and dominance to emotional reactivity and aptitude for training. 

"When a litter of pups was born, I knew exactly where I would be for each day of the next 12 months," wrote one of the lead investigators, John Fuller, in 1985.

The researchers set out to answer a host of questions. Are some dog breeds smarter than others? Do different breeds have different personalities? How important is canine parenting? If you disrupt a puppy's normal development, what happens? And might it be possible to breed a hyper-intelligent "super dog"?

From decoding doggie genetics to discovering the best way to socialise puppies, the findings from this mega experiment would change our understanding of dogs forever – as well as landing a final blow against eugenics.

World War Two had just ended, and a golden age for science in the US was beginning, with sizeable chunks of money funnelled into research. Scientists were free to think big, and large wads of cash were signed over without too many questions.  

The School for Dogs study, as it was affectionately nicknamed, was one of the beneficiaries, awarded funding of $632,000 (£465,000), or close to $9m (£7m) now – an unimaginable sum for an equivalent project today.

By this time, eugenics – the idea that selective breeding could achieve genetic superiority in humans – was discredited and considered inappropriate and unethical for mainstream study due to its role in Nazi atrocities during the Holocaust and the post-war focus on human rights. However, several prominent academics remained in thrall to the eugenicist agenda. They were still convinced that genetics was the main driver of behaviour, and that careful breeding could result in a supposedly better kind of human.

Among them was Alan Gregg, then director of the Rockefeller Foundation's Division of Medical Science and in charge of allocating the organisations' private philanthropic funds. Gregg was interested in modernising psychiatry and understanding the root causes of undesirable behaviours. "Delinquents, the criminal insane, the emotionally unstable, the psychopathic personalities," could all be explained, he believed, by bad genes. (In reality, how much our personalities and actions are determined by our genetics is far more complicated than this.) 

What he viewed as wasted expenditure on education was of particular concern to Gregg. A better understanding of genetics would force a realisation that man has "as much to gain intellectually by wise matings as by $800,000 high schools", he wrote in a 1945 letter. (The Rockefeller Foundation did not reply to the BBC's request for a comment for this piece.)

At that time, most genetics studies were carried out on fruit flies or rats, but Gregg alighted upon a new idea. What if researchers tried to breed an extremely smart dog – a creature that couldn't fail to capture the public imagination – to support his idea that intelligence was overwhelmingly hereditary? Gregg was prepared to stump up the cash for this hypothetical "super dog".

Dogs have long posed an interesting question for geneticists: how can different breeds vary so much in appearance? Can a Great Dane and a Pomeranian really hail from the same species?

Their overwhelming diversity was one reason that dogs were thought to be an ideal genetic test subject: a creature so diverse in appearance must surely exhibit a wide range of cognitive abilities and personality traits too. 

Fuller, a physiologist, and John Paul Scott, an animal behaviour geneticist who led the project, were also captivated by this problem. The dog study's findings, however, soon diverged from the aims of its benefactor.

The Rockefeller Foundation had hoped certain breeds would exhibit greater cognitive capacities. Accordingly, the dogs were subjected to a range of intelligence tests – such as maze tests where they had to locate food within a labyrinthine structure – and learning tests, where they were presented with the same problem repeatedly to see if their performance improved. 

Instead, it emerged that while certain breeds performed better on some tests, none exhibited a greater aptitude across all of them. Ultimately, the researchers concluded that no breed could be said to be "more intelligent" than another. 

Temperamentally, there seemed to be some differences between breeds. Fox terriers exhibited a greater capacity for violence (they were, after all, bred to be hunting dogs), though this was greatly mediated by context. "The same breed might be fearful in one situation and confident in another," Scott and Fuller wrote in 1965. "Basenjis were fearful of strange situations but not at all fearful of other dogs."  

Overall, Scott and Fuller proposed that their results offered a rebuke to the eugenicists and their notions of super-dogs created through superior breeding. The finding had important implications for humans too. "As far back as the Greeks… people have dreamed of godlike or heroic figures who combined the physical strength of a gorilla with the intelligence of an Einstein, the musical gifts of Beethoven with the beauty of a Greek God," they wrote.

The evidence from their study revealed why this was impossible. In a social animal, different traits are distributed across the population by design.

Take a trait like boldness. While courage in some dogs (and humans) might help see off danger, a more timid dog might help raise the alarm in the first place. A successful social group needs all bases covered.   

"The super-man is not to be found as an individual but as a well-developed human society," concluded Scott and Fuller.  

Eventually, more than spawning a plucky super dog, Scott and Fuller became interested in how a puppy's early experiences shaped the adult dog it grew into. At the time, Freud's theories of childhood development were hugely popular, while John Bowlby was working on his influential ideas about attachment styles, suggesting that the care-giving a child receives influences their future emotional life.

More like this:

• The true story of Germany's rampant raccoons

• This Greek island has a dark past. Now it's covered in rare seals

• The Dutch rewilding project that took a dark turn

Scott and Fuller began to think about attachment in the case of the dogs under their care. What would happen if puppies were reared in isolation? How would this impact their development? For this new experiment – which would never fly among researchers today – puppies were raised alone in large outdoor fields, with eight-foot-high fences around them through which food and water was delivered, so that they never saw human beings or other dogs.

By varying the length of time that the puppies spent alone, Scott and Fuller discovered that there seemed to be a "critical period" from four to 12 weeks of age: if an otherwise isolated pup interacted with a person or dog during this time, they could be socialised normally.  

However, "if you don't allow them to form attachments at this time, then you can never get a very satisfactory dog", Scott told oral archivist Susan Mehrtens in 1986. "Without any contact with people… they became, by the time of 14 or 15 weeks of age, just like little wild animals." 

Around 1958, the School for Dogs study wound down. The Rockefeller Foundation had declined to renew its funding when it became clear that no super-dog would be bounding out of the gates. The dogs were dispersed across labs in the US and Europe. A decade later, the boom times of America's scientific golden age came to an end. 

Even today, researchers remain dazzled by the scale and ambition of Scott and Fuller's efforts. "This lasted years, it involved hundreds of dogs," says Clive Wynne, director of the Canine Science Collaboratory at Arizona State University. "They had acres of facilities, they had dozens of staff. It's what we call 'big science'."

Researchers still credit Scott and Fuller for laying the groundwork for canine science. "The work was enormously influential in helping establish dogs as a serious subject for cognitive and behavioural science," says Vanessa Woods, director of the Duke University Puppy Kindergarten in North Carolina, US. "It helped pave the way for the field as it exists today."

Some of Scott and Fuller's experiments wouldn't fly today, though, says Wynne. Raising puppies in complete isolation would probably be considered too cruel to repeat – especially since the resulting "wild" and untameable puppies were ultimately euthanised. "Nowadays, if you're going to study people's dogs, you better not do anything to their dog that you wouldn't do to their child," he says.

In terms of scale alone, we are unlikely to see a rival to the School for Dogs any time soon. "The modern way of doing this is, we don't buy the dogs, we just borrow people's pets," says Wynne.

Still, some larger projects do exist. The Puppy Kindergarten at Duke University, for example, tested and trained 101 puppies to see whether they could predict which puppies would make it as guide dogs. "No one was ambitious or foolish enough to do the Scott and Fuller until we came along," says Woods with a laugh.

So far, her work has identified traits important to success like self-control, memory and how well the pups read social cues. But she agrees with Scott and Fullers' assertion there is no breed that is definitively "smarter" than another. "That finding has really held up." 

-- 

If you liked this story, sign up for The Essential List newsletter – a handpicked selection of features, videos and can't-miss news, delivered to your inbox twice a week. 

For more science, technology, environment and health stories from the BBC, follow us on Facebook and Instagram.