I have five roosters: 2 Buttercups, 3 Cochins. (Yes, I realize I should cull a couple for social reasons, but only two of the Cochins fight with each other, and they are getting better, so for now I'm letting them be. Anyway...) One Buttercup has decided to take over and be the Head Roo. At the time they were originally housed in the barn, both Buttercup roos were approximately the same level of, how can I put it, masculinity. Both had equally red, large combs, both had the same beginnings of little red wattles, both had a few hints of saddle feathers to come. When one roo decided to be the Head Roo, seemingly by mutual agreement, his comb got bigger and redder, and I could swear that the other roo's comb didn't grow half as much, and it looks a bit paler. The lowest-level roo, a small-ish Cochin, has a comb that is not much larger than a pullet's, but at one time I could swear it was as big and red as any of the others'. Do they actually change their hormone levels in response to social structure or something?