Duns

Dun is the "original" horse color, as in early horses were some variation of dun. A dun horse looks a lot like a buckskin, but it has markings that are referred to as "primitive markings", such as leg barring:



And dorsal stripes:



The original variation of dun was bay + dun + mealy. However, many more dun variations exist today.

A bay with the dun gene is a Zebra Dun:



A chestnut with the dun gene is a red dun:



A black with the dun gene is a grulla (pronounced grew-ya):



A palomino + dun is called a palomino dun or a dunalino. A buckskin + dun is called a dunskin.

An interesting fact about the dun color is that a horse cannot be a dun unless at least one of its parents was a dun also, unlike most other colors.