Although most people know that the vast majority of calico cats are female, they don’t always realize that calico refers to a color pattern and not a breed of cat. Let’s take a closer look at what exactly a calico cat is, what breeds can have calico colors, and why there aren’t more male calico cats.
What is a Calico Cat?
Calico cats are a popular choice for cat lovers due to their beautiful fur. But unlike a Siamese or Persian cat, Calico is not a breed of cat. A calico can be a Persian, a Maine Coon, a Manx, or several other breeds. For a cat to be called a calico, its coat must be three colors: black, white and orange. These three colors appear in patches on the coat, often with white in the highest concentration. Calico cats are named for their coat color, which is reminiscent of calico fabric once imported to Europe from India.
Calico cats are often confused with tortoiseshell cats and the terms may be used interchangeably in some regions. Tortoiseshell differs from calico in that the colors are blended or blended and contain little to no white, while calico has noticeable patches with a lot of white. Calicos can also have thinned fur, with fawn, cream, chocolate, and gray patches instead of the traditional bright colors of white, orange, and black.
What breeds of cats can be Calico?
Since we’ve established that calico is a color pattern and not a breed, does that mean any cat can be calico? Many breeds can produce calico cats, but not all. If you’re dying to own one of these tri-colored beauties, here are some of the most popular calico-colored breeds:
Why are so many Calico cats female?
It is a fact that almost all Calico cats are female as the chromosomes have a unique composition that determines the color variations in their fur.
The sex chromosomes (X and Y) determine whether a cat is male or female. Every cat has a pair of sex chromosomes with the possible combinations XX (female) and XY (male). The X chromosome also carries the gene that encodes the black and orange colors in a calico’s fur.
Female calico cats have two X chromosomes and therefore two color-coded chromosomes. Only if the cat receives an orange coded X and a black coded X is it Calico and expresses both black and orange coloring.
For example, a cat receives an X chromosome from its mother that codes for black fur and an X chromosome from its father that codes for orange fur. While it only takes one X chromosome to give the fur a certain color, females with two X chromosomes are special. During development, one X chromosome can overwrite the other, so that either black or orange can be the dominant color in an area. This special color development occurs in every single cell, causing one X chromosome to be switched off while the other remains active. With different dominant X chromosomes, a cat’s colors also vary, giving calico cats the colors orange and black.
But where do the white spots come from? To complicate matters further, calico cats must also inherit a gene unrelated to the X and Y chromosomes that codes for white fur.
Since male cats have an X chromosome that codes for black or orange and a Y chromosome with no color genes, they technically cannot be calico cats. They only express either black or orange, but not both.
How do male calico cats occur?
There are a few exceptions to the female-only calico rule: a genetic abnormality called Klinefelter syndrome and chimerism. Klinefelter syndrome occurs when a man inherits an extra X chromosome from his father or mother, making his genetic makeup XXY. Chimerism occurs when two embryos fuse very early in development, resulting in two different sets of DNA.
Both mutations are rare. These unicorn cats are almost always sterile and therefore cannot be used to breed further calico patterns.
Unfortunately, because male calico cats are born due to a genetic abnormality, they are often much less healthy than their female counterparts. It is possible for calico males to live long and healthy lives, but these special kittens require dedicated caretakers.
If you’re looking to welcome a calico cat into your life, there’s a good chance it’s a female. But maybe you’ll be lucky and find a unicorn cat – a male calico. Whatever color your cat is, you’re sure to enjoy the company of your new cat.