No, we’re not kitten – ah, kidding. Did you know that orange cats are “red” and grey cats are “blue”? At least, that’s what they’re called. The two primary color genes in cats are black and "red" (what you and I would call "orange."). Red cats are most often male (roughly 80%). The reason lies in the genes and chromosomes the cat has inherited. The red gene is carried on the X chromosome; for this reason it is sex-linked. Males normally only have one X chromosome and so if a male carries the red gene at all, he will be red. Females have two X chromosomes; only if both X chromosomes carry the Red gene will the cat be red. While red females aren’t as unusual as calico or tortoisehell males (more about that in a moment!) they are still uncommon.
Tiger Lily is an unusual (and very friendly!) Red female. (Hey, someone has to be the 20%!)
Although some red cats may appear to be a solid color, upon closer examination, you will nearly always see the pale stripes, whorls, or spots of the tabby. You will also usually see the distinctive tabby facial markings, including the "M" usually visible on the forehead of tabby cats.
Another cat with the Red gene is the tortoiseshell (mixed black and orange) and the calico (orange, black and white). Because both the black and red genes travel on the X chromosome, these colors appear in combination only in females, at least, 99% of the time. Very rarely, black and orange colors may appear in male cats, but these males are genetically abnormal (they have XXY chromosomes instead of the normal XY.) Again, if the orange patches are big enough, tabby stripes will be seen.
There is considerable disagreement on the exact meaning of the terms “calico” and “tortoiseshell”. At least, on the one end, a cat with defined patches of black and orange and white is a calico.
Piper, the mascot of Sandpiper Cat Blog (used with permission), clearly a calico.
However, there is disagreement on what to call a cat who has mottled black and orange coloration, but also has white. Tortie and white? Calico? Perhaps we should expect disagreement in a world where orange is red, and gray is blue! So, why is orange red and gray blue? Apparently, nobody actually knows, but the prevailing theory is that those were the names applied to the colors by judges when cat shows became commonplace in the Victorian era. Maybe they were colorblind!
If you want to read more about the complicated genetics that controls cat coat color, the International Cat Association has a detailed explanation: http://www.tica.org/cat-colors
Tiger Lily, Helen and Shadow are all available for adoption if you want to add some red, white and blue to your summer! Click their names below their photos to see their biographies on the FFGW website.