Is There a Connection Between Markings and Personality in Cats?
Q. I swear every calico I’ve ever met was crazy. Do you think differences in temperament are related to how a cat is marked?
A. I can’t say I know of any peer-reviewed studies linking feline markings to personality traits, but I can sure tell you that a great many cat lovers — and I include veterinarians among them — hold a suspicion that there’s a connection between color and temperament, especially when it comes to cats with orange fur. Calicos and tortoiseshells are often thought to be a little more unpredictable than other cats, while orange tabbies are often thought to be friendlier.
These cats aren't breeds as defined by their markings: Orange coloring appears in many breeds and certainly isn't uncommon in the wonderfully mixed-up cats known to veterinarians as DSH (domestic shorthair) and DLH (domestic longhair).
It's in the Genes
Before I get to what might be going on with a calico's temperament, I want to point out that there really is something special about orange cats. While the genes that produce tuxedos, tabbies and pointed cats (among other marking patterns) are distributed without regard for gender, the gene that produces orange fur (and what’s called “dilute” orange, sort of a warm tan) is strongly linked to whether a cat is male or female. That’s because that gene is displayed only on the X, or female, chromosome.
As you no doubt remember from high school biology, males have one X and one Y chromosome, while females have two X chromosomes. While male and female cats can get the orange gene from just one chromosome, for a cat to be a calico (orange, white and black patches) or tortoiseshell (same colors, but swirled together) requires two X chromosomes, which almost always means these cats are female. (The “almost” is a nod to the fact that about one in every 3,000 calico cats is male. These boys have an extra X chromosome — XXY instead of the XY of a normal male — making them what’s called Klinefelter males. They may be rare, but the trait doesn't reproduce, so these cats should be neutered like any other.)
Female cats, then, can be orange in calico, tortoiseshell or tabby patterns, but normal males can be orange tabbies only.
Here’s another way to think about the connection between markings and personality: Are females cats generally more unpredictable than males? Are male cats friendlier than females? If you think so — and I’m not sure that I do at all — then that’s as likely an explanation for why “all” calicoes/torties might seem “crazy” to you. Every calico you’ve met is likely to have been female.
But since there’s no large body of evidence on that, either, it’s just one of those things we cat lovers like to discuss when we're together.