Lord Morton's mare

Lord Morton’s mare was an equid hybrid and once an often-noticed example in the history of evolutionary theory.

[1] In the same issue "Particulars of a Fact, nearly similar to that related by Lord Morton, communicated to the President, in a letter from Daniel Giles, Esq."

[2] These circumstantial reports seemed to confirm the ancient idea of telegony in heritability: Charles Darwin cited the example in On the Origin of Species (1859) and The Variation of Animals and Plants Under Domestication (1868).

Biologists now explain the phenomenon of Lord Morton's mare as the result of dominant and recessive alleles.

Striped "primitive markings" are in fact commonly seen in domesticated horses, particularly those with a dun coat color.