Fascinating read. I loved reading about why calicos express orange or black because the color for orange is donated by one of the two parents on the X chromosome. Due to X expression being randomized, orange or black shows in patches on the cat.

Orange cats are typically male, calicos are products of black and orange parents. Ergo, females exhibit calico or tortie coats because they have two X chromosomes expressing traits from one parent or the other, assholes orange or black.