Think there are several enviromental factors, from what I've seen with first years hatches. Our flock is pretty varied
Our flock free ranges, we have chickens that hatched from the flock some broody raised some hatched in the incubator and kept separate from the flock until they were old...
I have a Barred Rock rooster and 4 hens in a mixed flock and they are sweet as can be other than the rooster he is another story all together but great at protecting his hens, other than the youngest who got picked on a lot, and she's only an issue when it's to cold to get out and free range. We...