It
is only the breeding, and the 'bracelet' of course. lol The same basic genetics exist in both. The ferals in America are descended from captives since Rock Doves are not a native species The Racing Homers have just been bred to develop certain traits more fully and reliably, ie speed and the desire and ability to return quickly for racing purposes. There are a lot of stray racers contributing to the feral gene pool and theoretically you could capture and band a nestling and it would be eligible to race. Comparable to racing a wild captured mustang against a thoroughbred horse.