Alligators like sharks move with ease through the water without making ripple, however sharks have fins to help them move, however alligators do not. Instead they use a series of muscles to move, they can shift their muscles and lungs so that they can dive and roll in the water.

When they need to dive they shift their rib muscles to change centre of buoyancy, this in turn forces their lungs to their tail so that they can dive.

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