I've got 7 pullets that are 18 weeks old. Although the ancona is the smallest of the group, she's also the most aggressive. She will get in front of another pullet, stretch up her neck and the feathers on her neck will stick out. Most of the other chickens will run away from her when she does that. The little black star will stare her down, and she backs off. Is that just normal behavior as they work out their pecking order? We've only had them for a week, but I haven't seen this behavior before this morning.