Curiosity 6: Horses' colors

Today was our dog Milo's 13th birthday, and he told us he wanted to have a special birthday walk at the Carmel River—on the River Trail in Garland Park. Who were we to refuse?

While there, we encountered several horses. Two were a beautiful golden color, with long black stockings. The third was brown, but what made him special was his costume: he was dressed in an orange cape with pumpkin motifs and sported a black witch's hat. The woman riding him was cackling delightfully (or maybe delightedly). Halloween is just around the corner.

The first pair of horses made me wonder about the nomenclature for their colors. I know "golden" isn't right. And here's some of what I've found out:

bay is a moderate reddish-brown color
chestnut is yellow-brown or golden-brown (used more commonly among english riding disciplines; cf. sorrel)
claybank is a dull brownish-orange color
cream is yellowish-white
dapplegrey is a horse with a grey coat having spots of darker color
dun, caused by a specific "dilution" gene, creates stripes along the back and on the legs and withers, dark tips of the ears, and a darker coloration on the lower legs, and a faded overall color; variations include red dun, grullo (a black horse with the dun modifier, making for a smoky color), and "dunalino" and "dunskin" (dun + palomino or buckskin, buckskin being a breed of horse, not a color designator) [the photo above, of Hollywood Dun It, is a dunskin—beautiful, no?]
fleabitten, having reddish-brown spots on a lighter background
mealy: spotted or mottled
palomino is a golden horse with a cream or white mane and tail
piebald is a black and white pied horse: in North America it's called a pinto
roan: having a bay (red roan), chestnut (strawberry roan) or black (blue roan) coat sprinkled with white hairs
skewbald is marked or spotted in white and any color except black (also called pinto in North America)
sorrel is a light brown to brownish-orange color (same as chestnut; used more commonly among western riding disciplines)

And that's only the beginning. There is a whole lot of genetics going on in horses, with many many color variations, such as the "cream gene," the "pearl gene," and the "dun gene" mentioned above. The buckskin breed, for example, has this going on genetically: "buckskin has the Extension, or 'black base coat' (E) gene, the agouti gene (A) gene (see bay for more on the agouti gene), which restricts the black base coat to the points, and one copy of the cream gene (CCr), which lightens the red/brown color of the bay coat to a tan/gold" (from Wikipedia).

I had no idea! I'm going to go with dun for the first pair we saw, and bay for the Halloween horse.

And here's a very happy Milo swimming in the river: