Is it true that calico cats are only females?

"Calico cats are nearly always female, due to genetics. Coat color in cats is a sex-linked trait, a physical characteristic (coat color) related to gender. Female animals have two X chromosomes (XX); males have one X chromosome and one Y chromosome (XY). The genetic coding for displaying black or orange color is found on the X chromosome. The coding for white is a completely separate gene.

Since females have two X chromosomes, they are able to "display" two colors (orange and black, or variations thereof) and white; creating the 3-color calico mix. Since males have only one X chromosome, they can only be orange OR black. It is more complicated than simply having the color genes--it is a complex process of dominant and non-dominate genes interacting on the X chromosomes, but that is the basis for coat color in calico cats.

In rare instances, a calico cat can be a male. In this situation, the cat has two X chromosomes and one Y chromosome (XXY). Cats with this chromosomal configuration are usually sterile (not able to breed). They might have some value for their rarity, but not for breeding purposes."

You're a bit confused about what colours make up calico. Calico (more often called Tortie and White in cat fancy) is Black, Red and White and Tortie is just Black and Red. Those other colour combinations you mentioned appear in millions of cats - including millions of males - in tabby patterned coats.

So no, your statement is incorrect but yes Tortie/Calicos are MOST OFTEN female - about 99%. I've seen a few Tortie males including one called "NARC" (Not a Regular Cat) at a TICA cat show. Here's some more info about Tortie/Calico http://en.wikipedia.org/wiki/Tortoiseshell_cat

There's also "Torbie" where the Red of Tortie can appear in a cat with a Tabby or Tabby and White coat. Cats with this coat pattern are also most often female. There's also Tortie in pointed cats (marked like a Siamese) called "Tortie Point". There's also a Dilute (also called Blue Tortie) version when the Black is diluted to Blue (dark gray) and the Red (orange) to Cream (light orange). Examples of each are here http://www.seregiontica.org/Colors/tortietorbie/to...

False. 99% of calicos/tortoiseshell cats ARE female but there is a small number of male calico/torties born. Has to do with a genetic fault. Normal cats have XX (female) or (XY) male. With a male calico, it has a XXY - giving it two colors instead of the normal one.

Most all male calicos are sterile and cannot reproduce. There is a very small number of fertile males that have bred and produced offspring. But they breed only as a "bicolor" - they cannot pass on both colors like their sisters can.

Acutally it's solid patches of red and black on white. That's calico.

98% of them are female, since the color characteristics for calico and tortoishell are gene linked to the female sex chromosone. However enough male calicos have been showing up to regularly get posted about on this list. It's not all that rare.

The male chromosone has a red tabby coloration gene linked to it, though there are female red tabbies as well.

not exactly. most calicos are female. with very few males. the reason this is is that genes decide the color.

basically it goes like this white is a completely separate gene for both males and females, the colors orange and grey are both ruled by the x chromosome. males (xy) can show one color (x). females (xx) can show both grey and orange. in the rare cases that a male cat shows all three colors it is because it is xxy. but cats with that chromosome configuration are very rare, and usually sterile. a similar thing happens in humans but i cant remember what its called.

Wow @ answer #1 ... ya learn something new every day! And as for the answer I've always heard so.

yes