cats

Lead author Chris Kaelin explained that orange cats produce more of an orange/red pigment called pheomelanin than they do a black/brown pigment called eumelanin, which isn’t too dissimilar from redheaded humans.

While human gingers owe their color to changes in the MC1R gene, the orange cat mutation is located in one gene called Arhgap36. The scientists say that the protein produced by this gene disrupts the biological pathway that determines a cat’s coat color, effectively shutting down eumelanin production and letting orange pigment take over.

As for why most orange cats are dudes, that has everything to do with a cat’s X chromosome. Males only get one, so if that X carries the mutation, it’s a ginger. Females, having two Xs, need both to be mutated to go full orange.