Are my tiger barbs mating?

I currently have 4 tiger barbs and they school nicely. I have noticed that 2 of them will pair off and go head to head and do an odd sort of dance. They stick together mouths touching and rotate around each other, they will do this for around 5 to 10 minutes then stop. I have witnessed this behavior on 2 separate occasions and have no clue what it is. Any help?

Brook

 

Sounds like they are disputing "rank" within the school.

 

My tiger barbs do the same thing. I believe they are esablishing "rank" in the school.

 

I read somewhere that when they do that, they are fighting.

 

I was glad to find this post...I found my tigers doing this too and wondered what they were up to. I also noticed that there were some coloration changes in them while they were having it out, with black mesh-like lines appearing while they were fighting, disappearing after they calmed down. Strange critters!