Well, since it is springtime, there are lots of babies entering the world. In fact, we have had 5 kids born within the past 3 weeks (3 bucks and 2 does), and we have 4 new barn kittens. Two are black and white and two are orange. So, I thought it might be fun to talk about cat coat colors.
Can you identify these colors and coat patterns? (answers at the bottom!)
From a genetic perspective, all cats are black, orange (the term used by professional cat people is red), or both. White can cover or co-exist with either color. Basically, what that means is coat color is determined by sex. Both black and orange are carried on X chromosomes. Since males carry one X and one Y, they will either be black or orange. If the colors are diluted, they can be gray (the professionals call this blue) or yellow (the professionals call this cream). For a male cat to have both black and orange, he will most likely have two X chromosomes. Orange females are uncommon.
Here is your trivia for the day: this condition of having XXY chromosomes is known as Klinefelter’s syndrome in people, and it is associated with difficulty developing secondary sex characteristics. These individuals are usually sterile.
Rarely, a black and orange (tortoiseshell) or black, orange, and white (calico) male will be fertile. This can be caused by mistaken identification of color, or it can be caused by chimerism where two embryos actually fuse in the womb.
Mistaken identification of color is actually more common than you would believe! As I mentioned above, coat colors include white (which can be seen as a solid color), black, red (orange), blue (gray), cream (yellow), brown, cinnamon (light brown with red overtones), and fawn (a dilute version of cinnamon).
To the coat color, you need to describe the coat pattern. You can have a solid, and as the name implies, this is all one color. Tabby is the most common coat pattern, but tabbies are further classified as mackerel, classic (blotched), spotted, or ticked (agouti). The mackerel has narrow stripes that run parallel to one another. The classic tabby has elaborate swirls with butterflies over the shoulders. The spotted tabby has stripes or swirls that appear to be broken into spots of color (the Ocicat is a good example of a spotted tabby), and the ticked tabby has multiple colors on each hair on its body with barring on the legs and tail (Abyssinians have this agouti tabby pattern). A bicolor is white with a second color. The other color can be solid or tabby. A bicolor can be a Harlequin where the coat is primarily white, or they can be called a van if they are mostly white with color only on the head and tail. A tortoisehell is orange and black or yellow and gray. A tricolor or calico is white, black, and orange or white, gray, and yellow. A colorpoint has dark color on the face, paws, and tail. This pattern is temperature related with the cooler parts of the body having the darker colors.
To further complicate the color process, some coats have special effects where the color changes from light to dark along the hair shaft. There are three varieties of special effects: tipped where only the tips of the hair are dark, shaded where half of the hair is light and half is dark, and smoked where most of the hair is dark with a light undercoat.
If you think this is all pretty confusing, you aren’t alone! If you want to practice (some of my colleagues make a game of identifying coat color and pattern), it will eventually all make sense.