labyrinth organ evolution

Question
what is the current theory behind the beta fish's evolution of its labyrinth organ?
my guess is that they lived in shallow pools that did not contain much oxygen,
so it was a benefit to breath straight from the atmosphere. am i close?

Answer
Hi Cade,
 Yes, that is what we assume happened.  Air breathing in fish has evolved many times (possibly as many as 17 times) and is almost always
the result of fishes living in oxygen-poor environments.

-- Ron
  rcoleman@cichlidresearch.com
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