The tarpan was a free-ranging horse subspecies of the Eurasian steppe from the 18th to the 20th century. It is generally unknown whether those horses represented genuine wild horses, feral domestic horses or hybrids. The last individual believed to be a tarpan died in captivity in the Russian Empire in 1909.
Tarpan
Replica of a horse painting from a cave in Lascaux
European wild horse coat colors
Illustration of a running individual
Breeding back is a form of artificial selection by the deliberate selective breeding of domestic animals, in an attempt to achieve an animal breed with a phenotype that resembles a wild type ancestor, usually one that has gone extinct. Breeding back is not to be confused with dedomestication.
Heck cattle were bred in the 1920s to resemble the aurochs.
Taurus cattle bull in the Lippeaue Reserve, Germany
Heck horse in Haselünne, Germany.
A Tamaskan Dog, bred to visually resemble a wolf