Here’s another article: https://www.livescience.com/why-cats-have-white-socks-on-paws.html
And it answers a question which was bugging me: Does it mean that the developmental quirk happened in all the white patches of a cat?
Looks like the answer is YES.
These distinctive fur colors and markings emerge while a cat embryo is developing. The cells that give cat fur its color first appear as neural crest cells, which are located along what will become the back, Lyons said.
Then, those cells slowly migrate down and around the body. If those waves of cells move far enough to meet each other on the cat’s front side, the embryo will be born a solid-colored kitten, such as an all-black or all-orange cat. Felines develop white feet, faces, chests and bellies when these cells don’t quite make it all the way.
Hmm…then my next question would be: What about “white” people?
Hahaha….
I won’t go there!
Indra’s white leg! Both his hind legs are white! So unique.