It is to help reduce water resistance and friction between the water and the seal,allowing it to swim faster to escape from its predator or to catch its prey.
Yes, they should have.
The reason is that fishes have streamlined body shape and since mudskippers are also considered as a specie of fish, it would also have the same characteristic.
because seals need to hunt for fish, and to swim faster, they have evolved so that their body has changed and became streamlined. having streamlined bodies makes seals swim faster and can change...