This is the silver fox, a fox with a recessive gene that dramatically changes its appearance from the animal that is much more familiar to us, the red fox. And in a fashion that for at least 150 years has made its beautiful fur highly-prized.
If you want to know where to join the queue for your very own pet fox, and I hope you don’t, visit Novosibirsk in Russia, where fifty years ago one man started breeding the wild out of the silver fox. What took thousands of years to turn the wild dog into our most loved companion, geneticist Dmitry Belyaev managed for Vulpes vulpes in just five decades. His farm can now boast the fully domesticated fox that loves nothing better than a cuddle and a belly rub. And when I say ‘fox’, I don’t mean one particular individual. I’m talking about a whole breed.
Foxes are harder than most animals to tame. They are said by those who’ve tried to be “highly-wired” and possessing “a stubborn wildness that is impossible to get rid of.”
But there is nothing complex about Belyaev’s method. Or high-tech. We’re not talking about CRISPR or ‘gene drive’ here. He has simply done what Man began all those millennia ago with cats, dogs, sheep, goats and cattle, and has carried on with ever since – selective breeding. He embarked on his mission in the 1950s, visiting fur farms around Russia, picking out foxes that seemed to him the friendliest. Those that hid in corners and made aggressive noises were ruled out.
Back on his farm with his starter foxes – 100 vixens and 30 males – once the vixens gave birth to their first cubs, Belyaev selected the tamest and most docile cubs from each litter, the ones that interacted with people best. It was as simple as that. The chosen 10% were not trained to become tame. They lived in cages and had minimal contact with humans, because the aim was to see how tameness could be bred, not how it could be taught.
Belyaev was trying to discover, for the Institute of Cytology and Genetics at the Russian Academy of Sciences, just how our distant ancestors had tamed the animals we now live with at home or on farms. How these evolutionary changes came about. There is some archaeological evidence that humans did attempt to ‘break in’ the fox in the distant past, but cats appear to have replaced them as better candidates for domestication. After Belyaev’s death in 1985, his intern Lyudmila Trut took over.
And so the process continues, litter after litter, generation after generation. By the early 2000s, the foxes were showing none of the fear or aggression of a wild animal. They seemed to have turned into (very pretty) dogs, greeting visitors with a lick and a wagging tail. By 2005-2006 the foxes had become playful, friendly and responsive to people’s gestures or glances. Their vocalisations were now different from those of wild foxes – more like dogs’.
And that wasn’t all. Surprising shifts in the foxes’ physical appearance started to emerge: there were changes in coat colour such as white spotting, legs got shorter, so did snout and tail, the skull widened and the ears got floppier. A fox with floppy ears?! They started to look more tame, more delicate, in a word ‘cute’. Even their natural behaviours changed. Now they’re able to mate out of season, and they produce on average one more cub per litter. They call it ‘domestication syndrome/.
By 2009 Ms Trut discovered a change in brain chemistry compared with the wild Vulpes vulpes population. The people-loving foxes have higher levels of serotonin – the ‘happiness hormone’, which also inhibits aggression. And less active adrenal glands, adrenalin being of course, the ‘flight or fight’ hormone, so vital for an animal in the wild. It makes sense then that foxes bred specifically for their tameness would have less adrenalin pumping round their systems. And less adrenalin means droopier ears!
“The proudest moment for us was creating a unique population of genetically tame foxes, the only one in the world,” said Ms Trut. She makes no mention of the other 90%, rejected from the experiment as still too wild, and killed for their fur.
The experiment continues. “The main current goals are focused on molecular-genetic mechanisms of domestic behaviour”, she says. But maintaining the work is expensive. Despite the sale of pelts, the institute struggles to finance itself. So, in the 1990s it began selling the foxes as house pets. You can have one imported into the USA for $8,900 if you want one. But, as I said, I sincerely hope you don’t.
Does the world need pet foxes? I think not, no more than we need their fur. What price the fox’s legendary cunning, cleverness, boldness, trickery and elusiveness? It appears that what the Russians have done is reduce this magical animal into not much more than a docile furry footwarmer.
Doesn’t the very beauty, allure, mystique of the fox lie in its unbroken wildness? There have to be better ways to make scientific discoveries than this.
Now read the startling 15th December 2019 update to this story:
Further reading: fascinating article about the silver fox fur boom on PEI
And listen to Inside Science 15 mins 15 seconds in.