Explain how a mutation might lead to adaptation

In the past, whales had legs. From whales no longer having legs, its technically a mutation. With this, it means they can no longer go onto land, so they learned to adapt to the water.

Used to water and cool climates, probably not thick coated or fluffy. they most likely have thin coats and have to survive to find food. sorry if this wasn't the answer you were looking for..: )