I don't have an answer but what a great observation! I am new too. I have 1 black star, 2 partridge rock, 1 speckled sussex, & 2 bantam ameracauna. We got them the 23rd.
You know.... I don't know! Everytime I look in on my little ones there just all hanging out together as a group, never notice if it was breed oriented, Hmmm I have to watch and see what happens, I know that they all have a special buddy it seems. LOL Sandy