Patches! He's such a cool guy. There is still quite strong debate regarding the underlying cause of his white patches. Many say they are purely genetic markings (ie unchanging markings he has always had), however I personally have always believed it is more like a genetic mutation that prevents recolouration of scar tissue. Normally Bottlenose dolphins' skin has very good recolouration properties. Even with more serious scratches or deeper wounds, the damaged tissue regains colour so when healed, the original wound is hardly visible. It can only be felt, and a scar line seen in close up. However there are cetacean species, like the Risso's dolphin and many beaked whales, where scratches quite explicitly do not recolour. On the contrary, the smallest blemish remains a stark, pure white. In these species the tally of scratches seems to serve a social function. I wonder if Patches carries a mutation that causes something similar to happen with him. Most of his white patches seem to have the shape of rake marks, and the others (like on his dorsal fin, around his mouth and on his melon) are places where dolphins often sustain damage either from feeding or raking/social interaction.