Female Dominance?

[tsasquatch]

I have three chickens, one that is about seven months old and two younger that are about three months old. Of the two younger pullets one is much larger than the other (almost bigger than the older buff orp). She occasionally kind of bites and holds on to the feathers at the back of the other two chickens necks. Is this a sign of challenging the dominance of the older hen or a sign of a cockerel getting ready to start mating?
Thanks

 

[Junkmanme]

I'd say you have a cockerel there.

 

[Teach97]

could be either...hens have a dominance oder just like roos. Heck I have a hen that smacks down roos!