Domesticated Silver Fox

The domesticated silver fox is a melanistic variant of the wild red fox bred under laboratory conditions at Russia's Institute of Cytology and Genetics, in an experiment begun by geneticist Dmitry Belyayev to test whether selecting purely for tameness could reproduce the physical traits seen in domesticated animals. After several decades and roughly 45,000 foxes, the selectively bred lines grew progressively friendlier and also developed traits nobody had selected for directly, including floppy ears, mottled coats, and changed skull proportions, along with lower adrenaline and higher serotonin. A 2019 international research team later questioned whether the experiment fully proves the broader domestication syndrome theory, while still valuing it for behavioral biology research. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/