I decided to read it and it just went on and on and on and on and on about the same crap so I just breezed through and quickly read little bits here and there and it basically said that is to do with low kinetic activity and blah, blah, blah, and something about the colour of the fish changes when it yawns over and over again.
Heres their conclusion.
In conclusion, it appears that the behaviour pattern yawning in fish is unlikely to be completely analogous to the behaviour of the same name in birds and mammals. In fish it serves asa mechanism to equate discrepancies between increased excitement level and lowered kinetic activity, raising the latter variable by its performance. It is, as has stated, simply a stretching movement and appears to be unassociated with breathing. In all vertebrates, however, it appears to be triggered by environmental stimuli and can also occur under the influence of endogenous factors, as stated above. It is likely that yawning may basically have the same causation in other vertebrate groups as has been demonstrated here for fish, but has developed secondary functions in the higher vertebrates, especially in social species where it acts as a signal in addition to being physiological regulatory mechanism.
How do they convince people to pay them to study this, I see my fish 'Yawning' from time to time and I don't give two hoots.
