It is a well established fact that domestic dogs (Canis familiaris) are capable of forming strong social bonds with humans (Homo sapien). When raised as pets, dogs are friendly, devoted, affectionate, eager to please, and voluntarily seek out human contact. These traits are missing in wild canine species.
In the late 1950s, Russian geneticist Dmitry Belyaeve began the Farm-fox Experiment to show that the silver fox (Vulpes vulpes) could be selectively bred to produce people-friendly offspring. The decades-long study revealed some interesting results.
Foxes for the breeding program were selected for their calm behavior, so it is no surprise to learn that trait was passed to offspring. The most unexpected change was the change in coat coloration that appeared in the eighth to tenth selected generations. A few pups had large areas of white on the head, chest, and tail--profoundly different from their wild relatives. The researchers also observed changes in reproductive cycle, skull size, and ear carriage (some pups had floppy ears).
Video clip from Nova TV broadcast about dogs (04:22)
Video clip about tame foxes (01:55)
A tame fox with tennis ball demonstrating dog-like behavior and showing dog-like coat characteristics. Photograph courtesy of Anna Kukekova.