I have 8 chickens now...3 of which I believe are roos. I had 3 I raised from about 2-3 weeks old, they are now around 2months old. Two days ago I bought 5 to add to my 3. I watched them to see "what" if anything might change, be challenged or simply accepted. Well, they still keep to their "gangs"...my original 3 stick together and my new additions all stick together...They sleep separately too. My 3 ward off the new five at every turn. I believe one of my new five is a roo because the one I raised whom I think is a roo also keeps the other chickens, especially the new roo away from food, water and whatever else he feels like running them off from. My 3 flew up on me while I was squatted in the coop and they settled down and began preening....and that's another question all together. Is that an unwise thing to allow them to do? They frequently like to sit on my arm or knee. I know that sometimes the things we humans like and think is cute at the time can be a nightmare later...I don't know if it's a good idea or not to let them do that. Any way...how long does it take for them to "re-work" the pecking order when new arrivals co-habitate what was singularly theirs?