Answer: Here are some of the differences:
- Sea lions have small ear flaps, whereas seals have only ear opening
- Sea lions can bring their back flippers under the body to help them move on land; seals cannot do this – they simply drag themselves along.
- Sea lions swim by moving their front flippers; seals swim by using their hind limbs in side to side strokes.
Source: Biggest Ever Book of Questions & Answers