Mary Allen
The fur of a tortoiseshell cat consists of black and red hair. Their drawing resembles the pattern on the back of a turtle – hence the name. Almost all tortoiseshell cats are female. This article explains why this is so.
What is a Tortoiseshell Cat?
The name tortoiseshell cat in itself is not an expression for an independent cat breed. Because this is the name of the unmistakable black-red color and pattern of the cat’s fur.
The pattern, reminiscent of a turtle shell, typically occurs as a two-tone fur structure in different cat breeds. These include both short and long-haired breeds such as:
- British shorthair
- British longhair
- German longhaired hair
- European shorthair
- Maine Coon
- Persian
- Siberian forest cat
What Does “Tortoiseshell” Mean?
The name tortoiseshell cat goes back to the Dutch word “Schildpad” – in German “turtle”. With a little imagination, you can see a certain similarity between the black and red fur pattern and the pattern on a turtle shell.
Breeders also use the term “tortie” for the black and red coat pattern. This comes from the English name for turtle shell “tortoiseshell”.
Tortoiseshell cats with a tabby pattern are also called “Torbie”. The made-up word is a combination of the words “tabby” and “tortie”. Tabby patterns are different, typical cat patterns. All tabby cats have an M-shaped mark on their foreheads.
Buy a Tortoiseshell Cat
The tortoiseshell drawing is a freak of nature. Therefore tortoiseshell cats cannot be bred according to plan. If you particularly like tortoiseshell cats or three-colored (tricolor) cats, you should turn your attention to the breeds already listed above.
The price for a tortie or tricolor cat is based on the price for the respective breed. The same applies to the keeping and care of a tortoiseshell cat what applies to the respective breed.
How is the Tortoiseshell Pattern Created?
All coat colors, shades, and patterns in cats can be traced back to two basic colors: black and red. The color pigment eumelanin is responsible for the black color, the color pigment pheomelanin for the red coloration.
These two pigments can be present in different proportions and thus result in different color variants. In tortoiseshell cats, some areas of fur are black and some are colored red.
The world of cats is not just made up of black, red, or black and red animals. There are numerous other factors that can affect the color and markings of a velvet paw.
The dilute gene, for example, is a dilution gene that brightens the color of the coat. Black becomes “blue” (blue-gray) and red becomes “cream”. In tortoiseshell cats, the dilute gene creates a blue-cream-colored tortoiseshell pattern.
The piebald gene, in turn, creates white spots on the fur. It turns a black and red tortoiseshell cat into a so-called three-colored lucky cat, also known as a tricolor cat among breeders.
Why Are Almost All Tortoiseshell Cats Female?
Almost all tortoiseshell cats are female. This is because the gene for a cat’s coat color is located on the X chromosome.
Females have two X chromosomes, one from the mother and the other from the father. Genetically speaking, a cat can be black and red – for example, if the mother has black and the father red.
As the kitten matures in the womb, one of the two X chromosomes is switched off. However, the shutdown does not take place smoothly. Sometimes the maternal, sometimes the paternal X chromosome is shut down. That means: sometimes the black fur color is suppressed, sometimes the red. This creates the different colored spots in the fur.
Hangovers only have one X chromosome and one extra Y chromosome. Therefore, genetically, they can only have one coat color: either black or red. A black and red spotted coat is not possible.
But there are no rules without exception: there are also hangovers who have two X chromosomes and one Y chromosome due to a genetic abnormality (Klinefelter syndrome). Because of the two X chromosomes, they can be black and red.
Cats with such an anomaly are always sterile. So they cannot reproduce.