My chickens seem to be in 2 flocks 1 coop/run

[Poodlemum]

But you will always find that birds that are similar in appearance will hang out together.

Yup! My two Bielefelders are always side by side, even though they were from the same batch as the WTB. The two lavender Orpingtons stick side by side even though they were a day or two younger, but brooded together. Karen and Kevin just do their own thing (Polish roos). I have no idea how many chickens total I have, but can quickly take a head count because I know which group is always together

 

[Granny23]

Wait.

Once everyone starts laying, they will form a more cohesive flock.
But you will always find that birds that are similar in appearance will hang out together.

That's funny because I have 2 adult Rhode Island Reds, a Barred Rock and a Buff Orpington who are a group. I do see once in a great while that Twinkie, the Buff Orpington is the one who gets picked on. Someone, I suspect it's Cookie the Barred is doing the picking as I saw her poke at her. Twinkie had a bloody comb a few weeks ago and we' ve never had any problems before. My new ones are a Delaware white and supposedly an Aracana but she is a RIR.
We bought our girls 2 at a time not being sure exactly what we were going to do as far as getting chickens.