2. Sea lions are creatures in the suborder Pinpoda, and the correct name of their limbs is Pinpoda.

3. Their fins are quite different from the legs of terrestrial mammals, and more like fish fins.

This is because sea lions live in the ocean, and the living environment of fish is the same.

So in the process of evolution, limbs gradually become more and more like fins.

6. This will make them move freely in the water at a faster speed.