why are all tortershell cats female?

Answer 1

Hi there
The reason being the gene for tortoiseshell is sex linked so only females are tortoiseshell. Also the reason why nearly all ginger cats are male although there are exceptions to every rule but it is complicated genetics stuff depending on what colour gene mum and dad are carrying. Hope that helps.

Answer 2

It's a genetic thing. Here comes the Science bit...

Coat coloration in cats is complex, and controlled by several genes. One gene involved has two alleles: the Orange allele, O, which is the dominant form, (i.e., XO), and produces orange fur; and the "Black" allele, "o", which is the recessive form, (i.e., Xo), and produces black fur.

For a cat to be a tortoiseshell or calico, it must simultaneously express both of the alleles, O and o, which are two versions of the same gene, located at the same location on the X chromosome. Males normally cannot do this: they can have only one allele, as they have only one X chromosome. Virtually all tortoiseshell or calico cats are females. Occasionally a male is born (the rate is approximately 1 in 3,000 [1]). These may have Klinefelter's syndrome, carrying an extra X chromosome, and will almost always be sterile or they may be a chimera resulting from the fusion of two differently coloured embryos.

The spotting gene causes white patches to cover the colored fur. Although there is no genetic difference, the amount of white is artificially divided into mitted, bicolour, harlequin, and van, going from almost no white to almost completely white.

In normal female tortoiseshell cats and in Klinefelter males, the position of the patches depends on which X-chromosome is active in each cell and which is inactivated to become a Barr body.

Hope that makes sense! lol :))

Answer 3

The gene for the orange coloration is carried on the X chromosome and it is recessive. So it takes two (XX) of them to express the color and therefore the cat will be female. Occasionally a cat has XXY and is male. This pattern can occur in humans too and the males are usually sterile.

I did read a whole book about that though ("Cats are Not Peas") and that XXY is not the only possible pattern that produces a male so the males are not necessarily 100% sterile. At one point in history there was even a registry of males who could or had breed successfully - not necessarily producing calico kittens though.

I'll add the author of the book to this post when I check it in my computer. The author is Laura Gould. There is only one copy in my county library system.

Answer 4

Some are male, but most are female. It's a genetic thing (tortoiseshell cats also have a tendency to be a bit spiky!), similarly most ginger cats are male and a lot of white cats are deaf.

Answer 5

Most are female (like 99%), but the the males are usually sterile. It would be very difficult and rare for 2 torties to get together and actually have kittens. Nature and genetics just prevent this from happening.

Answer 6

Hi, They are not by cat Bobbie is a tortoiseshell. He has got a sister Molly that lives next door but one.

Answer 7

They mainly are in britian but there are male tortershell cats in the rest of Europe, I have seen some in Portugal...

Answer 8

It is a genetic thing i'm told.There are very occasional males but they are almost all sterile.

Answer 9

They aren't, but it is true that all male tortoiseshells are sterile. I don't know why.

Answer 10

They're NOT !!!!!!!!!!!!