I can not tell any of my BO's apart. I have 6 of them. I can tell a couple of my RIR's apart, though, only because their combs and wattles are bigger and redder (come on eggs!) than the rest. Of course, this will change in time when the others catch up. However these same two also will follow very closely to my leg when I am out in the yard...hoping for treats! They get a little miffed if I don't give them any and will peck my leg, like "Hey, where's my treat?" So instead of individually naming my girls I just call them Biddy Girls, collectively. Now my roo has his own name, Rudy, but he doesn't know his name. They all come running when I go outside and start calling 'Biddy, Biddy, Biddy! Come on!' It works for me...