Differences Between Tortoiseshell and Calico Cats
Tortoiseshell and Calico Cat Color Pattern
Tortoiseshell and calico cats come in a great variety of the colors: black, red, and white. Unlike what some people think, they're not different breeds. Their differences lie in their special color patterns. In this article, I'll explain how the tortoiseshell pattern compares to the calico pattern. While a tortie coat might not have any white at all, a calico coat always include white. In my family, we had one tortoiseshell cat and two calico cats. One calico with plain colored patches and one with tabby colored patches. In The Netherlands, we use only one word for these cats: lapjeskat. In English, this means "patched cat."
Curiosity is the very basis of education and if you tell me that curiosity killed the cat, I say only the cat died nobly.— Arnold Edinborough
Why Tortoiseshell and Calico Patterns Are Different
Most tortoiseshell and calico cats are females. They have two X chromosomes, one for orange (XO), one for black (XB). They only pass one on to the next generation. Yet males have one X chromosome and one Y chromosome, which is either orange (XO) or black (XB). Below you'll find more detail about how this works:
Female XO + Male XO = orange
Female XO + Male XB = mixed orange+black pattern
Female XB + Male XO = mixed orange+black pattern
Female XB + Male XB = black
Whenever a male tortoiseshell or calico cat is born, the father most likely had an extra X chromosome, XXO or XXB, which is a rarity.
Pigment Genes in Cats
Pigment genes express in what we call melanocytes. When there is a mixed pattern, these genes surface to the skin. The colors mingle in random order, giving the cat that special brindled look. In tri-colored cats, there's a second gene interacting, which has no pigment at all. This results in either small or large white spots. This is why some cats look completely white but are not albino. They have a brindle pattern in their genes with a dominant white. This dominant white won't let the orange and black color surface to the skin.
The Only Difference Between a Tortie and a Calico Is the Presence of White
- The calico pattern has an extra spotting gene, which produces white, unpigmented spots. Those white spots can be either small or very big. The spotting gene overrules the color gene. You can have an almost white cat with a few colored patches or a colored cat with a few white spots.
Tortoiseshell cats, also called Torties, very often have only two colors, red and black. They have no white at all. The color can include black, orange (red), brown, black, cream, cinnamon, and blue. These cats often have a mottled or brindled coat. They can either be short-haired or long-haired, and the color patterns can vary from very dark to very light.
You can see that this cat has a very bright colored pattern of white, black and red patches on her head and body.
Which Color Pattern Is Your Cat?
My Calico Was a Stray Cat
One evening in 2002, I went into the barn and there she was: A cute, but skinny, teenage kitten with very big eyes. She was shy, but also hungry, and she ate until her belly was full. She may have come from a farm in the neighbourhood. They often have cats to keep the mice away. Or they threw her out of the car. Who knows?
That's how Red came to live with us. It took a lot of begging and spoiling before she allowed me to pet her. She never allowed me to pick her up though and hold her in my arms.
Cats With an Attitude
We discovered soon enough that Red must have had a difficult life before she ended up in our barn. She must have had some very bad experience with human encounters.
She comes to sit next to you, purrs a lot and actually loves petting. Yet when you pet her too much all the way down to her tail, she will grab you with her claws. Her ears go back to her neck, and she turns into a wild animal. You'd better get her off your lap by then. You can't pick her up, so the best way to do it is to stand up, and she'll jump off. She has always been like that, all nine years long, so we keep her away from visitors.
Would You Hang on to a Cat with a Nasty Attitude or Would You Get Rid of Them
What Is a Diluted Calico?
Dilute means less intensive. A dilute calico is a cat that has the same coloring pattern as a normal calico, but the red and black are not so bright. It looks like they're a bit washed out, so to speak. The black is greyish blue, and the red is rather creamy as you can see in the photo below.
Questions & Answers
My calico has cream, or off-white, areas on her in addition to black and light orange. Is she a steaight calico, or a torti, as her vet said?
The vet is right, when there is no real white it's a Torti.Helpful 21
Can a Calico cat be all white with hints of orange and light black?
Yes a Calico can be all white with either strong or diluted orange and black spots/hints. Even when the colored spots are the size of a pin head, it's still a Calico cat where the white has the upper hand.Helpful 14
How come my Siamese cat comes from the same mom as my tortoiseshell?
A cat will only ovulate after mating with a tomcat. In order to be sure she will have kittens, she will mate with as many tomcats as possible. That's why your two cats from the same mom, have different fathers.Helpful 13
Can a calico be of only two colours white and orange?
A calico has always three colors: white, black and orange.Helpful 12
Our Tortie kitten has a white belly and paws - is she a Cali-tort? She Also has one orange tabby front leg.
Your kitten is a calico. Torties don't have white spots.Helpful 10
© 2011 Titia Geertman