Species: marble fox
The marble fox or "Canadian marble fox" is the social media nickname for domesticated red foxes bred at the Institute of Cytology and Genetics at Novosibirsk, Russia, begun as an experiment by Dmitri Belyaev in 1959 to explore how wolves became domestic dogs. Collecting specimens from fur farms across the Soviet Union, Belyaev's team ran a selective breeding program based on behaviour, originally selecting for tameness and later for foxes that specifically sought human attention. Today, the experiment routinely produces generations that look and act like domestic dogs; Belyaev predicted that lower adrenaline levels would cause physiological changes, including changes to the production of melanin, resulting in the namesake "marble" or mottled fur pattern.
While the initial experiment primarily sampled silver fox morphs (believed to be the most tameable), the project has resulted in a variety of colour morphs including red, silver, platinum, and cross; despite the 'Canadian' moniker, the iconic 'Georgian White' is exclusive to the Institute.