The Domestic Silver Fox


Foxes have long been branded as being cunning, mischievous, and manipulative characters in fables. But how would they fare if given characteristics such as friendly, happy, affectionate and loyal? Believe it or not these are some of the characteristics that arose from an experiment conducted by the late Dmitry Belyaev in Novosibirsk, Russia.

A geneticist in Stalinist Russia, Dmitry Belyaev sought to experiment how does domestication happen by selectively breeding the Russian Silver Fox. Prior to creating his fox farm facility Belyaev was under intense scrutiny for his strong beliefs in Darwinian genetics. This was due to the stigma surrounding genetics at the time. Trofim Lysenko was the director of Soviet Lenin All-Union Academy of Agricultural Sciences and advisor to Joseph Stalin. Lysenko was convinced that genetics was a bourgeoisie, fascist pseudo-science due to the adoption of genetics in fascist Germany and the implementation of eugenics. Lysenko was so adamant about genetics being disbanded from the sciences that, following the approval from Stalin, many Russian geneticists were executed. One of these scientists was Dmitry Belyaev’s own brother, Nikolay, who was exiled to a labor camp where he later died. Filled with fear for his life Dmitry Belyaev fled to Novosibirsk, Russia. A strong-minded Darwinian, Belyaev vowed to continue his research on genetics in secret.

Belyaev became the director of the Institute of Cytology and Genetics under the guise of researching fox fur in the attempt to create the finest and most profitable fur. Fur trading, a large Russian industry, was a successful cover. Belyaev and his team collected Russian Silver Foxes and did a simple aggressiveness test to determine which foxes would be allowed to breed and which would be sold for their fur. The Russian Silver Fox is the same species as the more common Red Fox, Vulpes vulpes, found here, in the United States. The test to determine aggressiveness was simple. Belyaev and his team would test on juvenile foxes by approaching a youngling in their cage. They would extend their arm as if to try and touch the pup. Usually, the feral fox puppies would cower in the corner of the cage and make a high-pitched bark signaling fear. These were the juveniles with more aggressiveness. But sometimes, about one in twenty, a juvenile fox would be born without the inclination to cower and bark. Some of the juvenile foxes seemed unfazed by the human’s presence. These would be the foxes that would begin the long line of artificial selection in Belyaev’s fox farm.


Belyaev and his team bred the most docile foxes in order to create the most docile young. Each pup born in the farm was evaluated for aggressiveness and only a percentage of pups born were allowed to breed and create the forthcoming generation. Belyaev’s research on breeding out aggressiveness in foxes also had a parallel study, one in which bred for aggressiveness. They would not only select the friendliest foxes for breeding, but also the most aggressive. The foxes that were caught in-between were sold for their fur.

After only four generations, lasting from 1959 to 1964 foxes that had been bred for being nice began to show signs of domestication like wagging their tail when a human came close to them. By 1970 the foxes were loyal to humans and followed them like a dog would. They would even jump into the arms of the scientists at the facility and lick their faces. The team continued their research until an astounding new byproduct of their artificial selection presented itself in 1980. The foxes that were being bred for niceness were becoming physically different. Their ears started to flop, their tail’s curled, their teeth became smaller, their bones became smaller, and most observable- their coats changed. Foxes began to appear with white, orange, and even spotted coats. These results were not initially expected and created a huge outpour of evidence supporting how the domestication of other animals, such as the dog from the wolf, can create such variety in physical appearance. This extreme change in physical appearance as well as personality had occurred in a little over a decade. Ten years! Dogs have evolved from wolves over thousands of years and Dmitry Belyaev had created a domesticated fox in ten years.


So on one side of the fox farm there were affectionate, happy, tail-wagging, face-licking foxes that whimpered for attention when humans walked past. On the other side of the fox farm were the aggressive foxes. Belyaev’s team bred just as many generations of the aggressive foxes. These foxes grew to have extreme anger at even the sight of a human. They would become wild, snarl, bark, and attempt to bite at the human through their cage. These foxes did not have the type of juvenile traits attributed to the nice foxes.


Beylaev and his team used artificial selection to breed for nice foxes and ended up creating foxes that are basically trapped in their juvenile phase. The adrenal glands in these foxes are severely slow and undeveloped resulting in the inability to transmit neurochemicals that trigger ear development, skin pigmentation, and other physical traits that would otherwise allow the fox to develop into a feral adult. Many theorize the same delay in development or a permanent juvenile phase is what has created the common domestic dog.

The Institute of Cytology and Genetics’s fox farm has fallen under extreme financial difficulties since the demise of the Soviet Union. A majority of their funding comes from selling their domesticated foxes as pets to interested buyers all over the world. A fox can run you upwards of eight thousand dollars. These foxes still consume raw meat and require an outdoor enclosure as their permanent residence. So, are foxes the new pet craze? Many satisfied fox owners seem to think so.