Dolphin Physics

(SFX: Splish Splashing in the water, beach ambience) 

     WITH SUMMERTIME APPROACHING, MILLIONS OF AMERICANS WILL START HEADING
OFF TO THE BEACH AND MANY OF THEM WILL WORRY JUST HOW THEY'RE GOING TO LOOK
IN THEIR BATHING SUITS.  BUT BEFORE YOU START WORRYING TOO MUCH ABOUT THAT
EXTRA FAT, YOU SHOULD KNOW THAT SOME OF THE BEST SWIMMERS AROUND RELY ON
THAT FAT TO GET THEIR SPEED.  BIOLOGIST ANN PABST AT JAMES MADISON UNIVERSITY
SAYS THAT DOLPHINS MAKE USE OF A LAYER OF BLUBBER UNDER THE SKIN TO KEEP
THEIR SWIMMING STRONG AND GRACEFUL. 

     Pabst: "We're beginning to find that the hydrodynamic shape of the dolphin is really sculpted by
its blubber."
     
     THE DOLPHIN'S BLUBBER HAS THE CONSISTENCY OF OUR TENDONS.  PABST AND
HER COLLEAGUES STRETCH AND PULL AT THE BLUBBER USING THE SAME TOOLS THAT
ENGINEER'S DO WHEN TESTING THE STRENGTH OF CONCRETE.  SHE'S FOUND THAT JUST
AS CONCRETE CAN BUILD A FRAMEWORK FOR  A HOUSE, THE BLUBBER HOLDS THE SKIN
IN PLACE SO THAT IT DOESN'T RIPPLE WHILE SWIMMING.   THE DOLPHIN SAVES  ENERGY
AND, THEREFORE, MOVES FASTER IF IT CAN KEEP ITS BODY SMOOTH AND SLEEK--JUST
THE WAY AN AERODYNAMICALLY BUILT CAR WILL TRAVEL FASTER THAN A CLUNKY ONE. 

     Pabst: "At the speed that they swim, large scale deformations of the skin can very much
increase. . . the energy needed to drive a body through the water and somehow the dolphins skin
resists those large scale deformations."

     BLUBBER MAY STILL NOT TURN YOUR BELLY FLOP INTO A SWAN DIVE, BUT IT
CERTAINLY KEEPS THE DOLPHINS LOOKING PRETTY.