| Russian domesticated red fox | |
|---|---|
| |
Domesticated
| |
Scientific classification 
| |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Carnivora |
| Family: | Canidae |
| Genus: | Vulpes |
| Species: |
V. vulpes
|
| Binomial name | |
| Vulpes vulpes | |
The Russian domesticated red fox is a form of the wild red fox (Vulpes vulpes) which has been domesticated to an extent, under laboratory conditions. They are the result of an experiment which was designed to demonstrate the power of selective breeding to transform species, as described by Charles Darwin in On the Origin of Species. The experiment was purposely designed to replicate the process that had produced dogs from wolves, by recording the changes in foxes, when in each generation only the most tame foxes were allowed to breed. In short order, the descendant foxes became tamer and more dog-like in their behavior.
The program was started in 1959 in the Soviet Union by zoologist Dmitry Belyayev and it has been in continuous operation since. Today, the experiment is under the supervision of Lyudmila Trut, in Russia, at the Institute of Cytology and Genetics in Novosibirsk.
Genetic experimentation
Initial premise and hypothesis
The experiment was initiated by scientists who were interested in the topic of domestication and the process by which wolves became domesticated dogs. They saw some retention of juvenile traits by adult dogs, both morphological ones, such as skulls that were unusually broad for their length, and behavioral ones, such as whining, barking, and submission.
In a time when centralized political control in the fields of genetics and agriculture promoted Lysenkoism as an official state doctrine, Belyayev's commitment to classical genetics
had cost him his job as head of the Department of Fur Animal Breeding
at the Central Research Laboratory of Fur Breeding in Moscow in 1948. During the 1950s, he continued to conduct genetic research under the guise of studying animal physiology.
Belyayev believed that the key factor selected for in the
domestication of dogs was not size or fertility, but behavior:
specifically, tameability. Since behavior is rooted in biology, selecting for tameness and against aggression means selecting for physiological changes in the systems that govern the body's hormones and neurochemicals.
Experimentation
Belyayev decided to test his theory by domesticating foxes, in particular, the silver fox, a dark color mutation of the red fox. He placed a population of them under strong selection pressure for inherent tameness. According to Trut:
The least domesticated foxes, those that flee from experimenters or bite when stroked or handled, are assigned to Class III. Foxes in Class II let themselves be petted and handled but show no emotionally friendly response to experimenters. Foxes in Class I are friendly toward experimenters, wagging their tails and whining. In the sixth generation bred for tameness we had to add an even higher-scoring category. Members of Class IE, the "domesticated elite", are eager to establish human contact, whimpering to attract attention and sniffing and licking experimenters like dogs. They start displaying this kind of behavior before they are one month old. By the tenth generation, 18 percent of fox pups were elite; by the 20th, the figure had reached 35 percent. Today elite foxes make up 70 to 80 percent of our experimentally selected population.
Belyayev and Trut believed that selecting for tameness mimics the
natural selection that must have occurred in the ancestral past of dogs,
and, more than any other quality, must have determined how well an
animal would adapt to life among humans.
Results
Russian scientists achieved a population of domesticated foxes that are fundamentally different in temperament and behavior from their wild forebears. Some important changes in physiology and morphology became visible, such as mottled or spotted colored fur. Some scientists believe that these changes obtained from selection for tameness are caused by lower adrenaline production in the new population,
causing physiological changes within relatively few generations
yielding genetic combinations not present in the original species. This
indicates that selection for tameness, e.g. did not flee, produces
changes that are related to the emergence of other dog-like traits, e.g.
raised tail, coming into heat every six months rather than annually. These seemingly unrelated changes are a result of pleiotropy.
The project also bred the least-tameable foxes to study social
behavior in canids. These foxes avoided human contact as do their wild
behavioral phenotypes.
Similar research was carried out in Denmark with American mink.
Current project status
Following
the demise of the Soviet Union, the project ran into serious financial
problems. In 2014, officials stated that the number of foxes was never
reduced and is still stable at about 2,000. As of August 2016, there are 270 tame vixens and 70 tame males on the farm.
In another published study, a system of measuring fox behavior was described that is expected to be useful in QTL mapping to explore the genetic basis of tame and aggressive behavior in foxes.
The sculpture "Dmitriy Belyaev and the Domesticated Fox" was
built near Institute of Cytology and Genetics (Novosibirsk) the honor of
the 100th anniversary of the birth of Dmitry Konstantinovich Belyaev.
The tamed fox gives the scientist a paw and wags its tail. Konstantin
Zinich, sculptor (Krasnoyarsk) says "The philosophy of touching a fox
and a man is rapprochement, kindness, there is no aggression from the
fox – it was wild, and he made it genetically domesticated."
Morphology
Russian domesticated foxes exhibit a variety of coat color mutations,
including red, silver (black), platinum, cross, and Georgian white, the
lattermost being a color exclusive to the Russian breeding project.
