Chimera Cat

This is Venus, and she's what's known as a chimera cat. 

In her mother's uterus, this cat started out as a set of twins, and then the cells fused together to create a single animal with two entirely different genetic profiles. She's not a calico, with several fur patterns randomly appearing in her fur, but her face is literally split straight down the middle, one green eye, one blue. She is, in essence, her own fraternal twin.

A Chimera is a mythological beast, a mish-mash of several different animals. Obviously, Venus is all cat, but I can understand how the term applies. I heard a veterinarian once say that Mother Nature doesn't like straight lines, but apparently that's not always the case.