oscar behavoir!!

Question
We have 5 small oscars in our tank. Don't worry, we will be separating them into different tanks. Anyway, I was wondreing why our smallest ocscar turns on it's side when our largest oscar comes around it. It's almost like it's playing dead. Another thing, why do they shake their tailfin?Is that a sign of aggression?
It would be cool if you know the answers to these questions.
Thanks!!

Answer
Hi Allicia,
  What you are seeing is how oscars sort out their "pecking order".  They use these displays to communicate who is boss and who isn't. It is a lot of fun to watch once you know what's happening and see who does what to whom and how they react.

-- Ron
  rcoleman@cichlidresearch.com
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