Domesticated silver fox

A Russian Silver Fox, the kind used by scientist Dmitry Belyaev for genetics research in Novosibirsk.

The domesticated silver fox (marketed as the Siberian fox) is a domesticated form of the silver morph of the red fox. As a result of selective breeding, the new foxes became not only tamer, but more dog-like as well.

The result of over 50 years of experiments in the Soviet Union and Russia, the breeding project was set up in 1959^[1] by the Soviet scientist Dmitri Belyaev. It continues today at The Institute of Cytology and Genetics at Novosibirsk, under the supervision of Lyudmila Trut.

The Russian researchers have partnered with the American company SibFox to distribute these foxes as pets internationally.^[2]

Initial experimentation

The experiment was initiated by scientists who were interested in the topic of domestication and the process by which wolves became tame 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 Lysenkoism was an official state doctrine, Belyaev'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.^[3] During the 1950s, he continued to conduct genetic research under the guise of studying animal physiology.

Belyaev believed that the key factor selected for in the domestication of dogs was not size or reproduction, but behavior; specifically, amenability to domestication, or tameability. He selected for low flight distance, that is, the distance one can approach the animal before it runs away. Selecting this behavior mimics the natural selection that must have occurred in the ancestral past of dogs. More than any other quality, Belyaev believed, tameability must have determined how well an animal would adapt to life among humans. Because 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. Belyaev decided to test his theory by domesticating foxes; in particular, the silver fox, a dark color form of the red fox. He placed a population of them in the same process of domestication, and he decided to submit this population to strong selection pressure for inherent tameness.^[4]

The result is that Russian scientists now have a number of domesticated foxes that are fundamentally different in temperament and behavior from their wild forebears. Some important changes in physiology and morphology are now visible, such as mottled or spotted colored fur. Many scientists believe that these changes related to selection for tameness are caused by lower adrenaline production in the new breed, causing physiological changes in very few generations and thus yielding genetic combinations not present in the original species. This indicates that selection for tameness (i.e. low flight distance) produces changes that are also influential on the emergence of other "dog-like" traits, such as raised tail and coming into heat every six months rather than annually.

The project also investigated breeding vicious foxes to study aggressive behavior. These foxes snap at humans and otherwise show no fear.

Current project status

Following the demise of the Soviet Union, the project has run into serious financial problems. In 1996, there were 700 domesticated foxes, but, in 1998, without enough funds for food and salaries, the project scientists had to cut the number to 100. Most of the project expenses are covered by selling the foxes as pets, but the project remains in a difficult situation and is looking for new sources of revenue from outside sources.

On November 22, 2005, the journal Current Biology published an article about the genetic differences between the two fox populations.^[5] In this study, DNA microarrays were used to detect differential gene expression between domesticated foxes, non-domesticated foxes raised at the same farm as the tame foxes, and wild foxes. Forty genes were found to differ between the domesticated and non-domesticated farm-raised foxes, although about 2,700 genes differed between the wild foxes and either set of farm-raised foxes. The authors did not analyze the functional implications of the gene expression differences they observed.

On November 21, 2007, the journal Behavior Genetics published an article about continuing research using both the domesticated and non-domesticated foxes developed by the Institute of Cytology and Genetics of the Russian Academy of Sciences.^[6] In this paper, the authors identify a system of measuring fox behavior that is expected to be useful in QTL mapping to explore the genetic basis of tame and aggressive behavior in foxes.

See also

• Domestication
• Experimental evolution
• Neoteny
• Perro Yaghan
• The Greatest Show on Earth: The Evidence for Evolution, 2009 book by Richard Dawkins

References

1. ^ Early Canid Domestication: The Fox Farm Experiment, p.2, by Lyudmila N. Trut, Ph.D., Retrieved February 19, 2011
2. ^ Sibfox FAQ
3. ^ Ratliff, Evan. "Animal Domestication: Taming the Wild", "National Geographic", March 2011.
4. ^ Genetics of Dog Breeding
5. ^ Jazin et al.: "Selection for tameness has changed brain gene expression in silver foxes." Current Biology, Vol. 15, R915-R916, November 22, 2005, DOI 10.1016/j.cub.2005.11.009
6. ^ Kukekova et al.:"Measurement of segregating behaviors in experimental silver fox pedigrees." Behavior Genetics, Vol. 38, Number 2, March, 2008, 0001-8244 (Print) 1573-3297 (Online), DOI 10.1007/s10519-007-9180-1

External links

• Fox Domestication: website from Cornell University with detailed information (videos and articles)
• SibFox - Tame foxes distribution
• Early Canid Domestication: The Fox Farm Experiment, by Lyudmila N. Trut, Ph.D.
• An Additional NYTimes Article
• Nice Rats, Nasty Rats: Maybe It’s All in the Genes, New York Times article
• CBBC News Article
• Press release from Eurekalert.org
• My Little Zebra - New Scientist article
• American Scientist, The Fox Farm Experiment Free full text
• "New Nice" WNYC RadioLab Story; contains audio, video, interviews, and other links. (Public Radio)
• Soviet Scientist Turns Foxes Into Puppies
• Horizon S48E08 (2010): The Secret Life of the Dog - BBC
• Explorer: How Man Tamed the Wild - National Geographic
• Taming the Wild, by Evan Ratliff - National Geographic, March 2011