Dolphin speed - solved?

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   I came across these interesting research findings recently - thought I'd share.

      New research has shown how dolphins achieve their blinding speeds.

Gray's Paradox - named after British zoologist Sir James Gray -
proposed that dolphins simply do not have the strength to swim so fast.
 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 400lb of force with their tails.

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."

To determine this, Professor Wei used a new method of measuring the
movement of water that he originally developed to track Olympic
swimmers. 	

The technique employs digital particle image velocimetry, which
measures the speed of water movements around a swimming dolphin or
human. 

      Retired US Navy dolphins Primo and Puka were filmed swimming through a tank filled with millions of tiny bubbles.

      Software tracked the movement of individual bubbles, determining their speed and direction, and assigning them a colour.

Professor Wei then used force measurement concepts from aerospace
research to translate those velocities into a force that the dolphins'
tails were producing - nearly 200lb on average. 
 When "walking" - keeping upright mostly above water
with powerful flips of their tails - the dolphins produced as much as
400lb of force. 

      Professor Wei will go on to study the motion and force generation of other sea animals.
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So it seems a culmination of muscle power and streamlining allow dolphins to reach such high speeds in a viscous environment like water. I've had a bit of trouble trying to find microscope (light or electron) scans of a dolphin's tail muscle cells. I'd be very interested to take a look at one, if anyone comes across one...as you do.
I look forward to findings about other sea animals, especially some species like the Great White, Thresher and Mako sharks. 
Regards,

- Knights -