A swimming elephant effectively snorkels. The air it breathes through it's trunk is at 1ATA. However, the rest of it's body, the blood vessels etc, are at a far higher pressure because it's a number of meters UW. How does the elephant therefore manage to effect the oxygen transference between it's lungs...at 1ATA...and it's bloodstream...at a far higher pressure....without the blood vessel walls popping?
(not sure if this is really the right forum for this, if not, feel free to move it! )
(not sure if this is really the right forum for this, if not, feel free to move it! )