My favorite #CatFact on this beautiful #Caturday is that most calico cats are female! The regions of different colors are due to different X chromosomes being "turned on" for the fur color (at least that's how I understand it in my poor grasp of genetics)
So if you see a rare male calico, chances are it has XXY chromosomes, not XY.
@_astronoMay Another thing I love about calicoes: the size, shape and position of regions are not only bound to genetics but to embryogenesis too.
And it's difficult to clone calicoes, because of that and "random inactivation of one of the X chromosomes" (thanks Wikipedia for the term): the first cloned cat, "Carbon copy" hadn't the same pattern as her genetic donor (in fact she even wasn't a calico like her donor) . See https://en.wikipedia.org/wiki/CC_(cat), it's really interesting.
@lamecarlate wow, that's super interesting!
(Naturally I had to go track down pictures of the original cat, she's an adorable chonker!)
Erin M. May, PhD
Lamecarlate