I'm not a huge fan of internet cat photos/videos so I'm just now seeing this one. Her name is Venus. Wow! Except for still having both eyes, this cat is a dead ringer (pun intended) for the world's greatest assassin. Even the orange and black are on the correct sides of her face. It's been claimed that she is a "chimera," which a single organism made from two originally distinct embryos that fuse together soon after conception. However Columbia University geneticist, Prof. Virginia Papaioannou, explained to New Republic.com that Venus, while looking like a total bad-ass, is simply a normal calico cat whose genes randomly expressed this way due to something called "X-Inactivation Mosaicism."
I'm certainly no geneticist, but I'll try to summarize Prof. Papaioannou's explaination here. All females have two x-chromosomes replete with a full set of genetic information, but will only need half of it to create a healthy organism (this is why males can be healthy organisms with only one x-chromosome). Because females only need one set of genetic instructions per cell, one of the x-chromosomes per cell randomly becomes inactive. So for females, gene expression is considered to be "mosaic" with half of the genetic information coming from one x-chomosome and half come from the other. In Venus' case, one x-chromosome contributed black fur information and the other contributed orange. The random nature of x-chromosome inactivation per cell resulted in Venus' Deathstrokesque facial markings. I may have been a few years late with this story, but where else would you get the genetics lesson that goes with it? Am I right?
