Hens cock fighting?

[chicksnchicks]

I have 2 bantams who I bought together, they are around 15 weeks old now. They sometimes run up to each other touch chests and fluff their neck feathers like my roosters do. Why would they be doing this to each other?
I've seen "their" rooster do it to one of them. Does he just not except them so they behave this way with each other?

 

[sourland]

Pullets as well as cockerels will engage in play fighting. If they are cockerels it may become more aggressive as they mature.