Seals and sea lions look very similar and it’s sometimes difficult to tell which is which. Both of these marine mammals swim with flippers and can be found in oceans all over the world. One has visible ear flaps while the others’ ears have no external flaps. One swooshes through the water using their back flippers and the other uses their front flippers to swim. On land, one bounces along and the other can “walk” on their flippers.