I'm curious about them, too. My parents had a cat while I was growing up that was entirely black until she was about 6 or 7 years old. Then her hair turned color and she had the distinctive tortoiseshell markings. I've always wondered if she was just a fluke of nature or something. Her siblings are all calico; as was her mother.
That is so odd, I wonder if it just took some time for her true markings to come through. I had a cat Nova she was all black but if she sat in the sun just right you could she her tabby markings, truely beautiful.
__________________ Freya Rose, born silent Feb 26,2007 little one, Coming Soon May2008
It's a coat color. Is tortoise shell the same as calico? Calico cats are always female. It is a sex linked trait that only females can exhibit. It is attached to the X chromosome. Females have two of them. If two X chromosomes are inherited you have a female and if the trait is attached to both of these X's you will have calico coloring. You need two of these traits together to get the coloring.
They are beautiful cats!
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