"But researchers at the Rensselaer Polytechnic Institute in the US have now studied the movement of water around dolphins as they swim.

"The results show that dolphins can exert as much as 180kg (400lb) of force with their tails.

"When "walking" - keeping upright mostly above water with powerful flips of their tails - the dolphins produced as much as 180kg of force.

"Gray had supposed they could produce less than a tenth of this amount, and imagined that something about the dolphins' skin allowed them to overcome the force of drag in the water and reach high speeds.

" 'For the first time, I think we can safely say the puzzle is solved. 'said Tim Wei, the Rensselaer scientist who led the study.

" 'The short answer is that dolphins are simply much stronger than Gray or many other people ever imagined.' " 

Between Flipper and Sir James Gray, Gray never had a chance.  Congratulations, Flipper