Cats have a specific gene that happens in-utero that creates the Tabby stripes and the M pattern on their heads. Science was all “why?” and so they found out the pre-pattern came from the gene Dkk4 that creates thick and thin patterns of skin which then determines the hair color. If you care more about the science you can find it here! If you don’t… here’s a picture of the cat I live with with all of her pre-determined stripes.

-Nikki