There is ALWAYS a pecking order, I think. There are only issues when a chicken does not kow her place in the order, or challenges it. I only have 3 chickens, and it it is obvious who the top hen is. It is also quite obvious who the lowest hen is. The bottom rung chicken "Chickie" gets harassed quite a bit by the other two, but I think it's more psychological than physical. She's never been injured that I could see. She just is always the last to get to eat, and probably gets last choice for roosting spots at night. It's kind of sad to watch. Kind of like middle school and high school----the popular girls vs the non popular girls. Poor Chickie just has to keep her head down.