Some evolutionists have tried to tackle this problem by claiming that many millions of years ago, long after mammals had fully developed on land, there was a type of wolf that lived near the edge of the sea. This creature learned to like fish, so he spent much time jumping into the water to catch them. After
quite a while doing this, the wolf-like creature began to swim out farther into the waves after its food. It spent more and more time in the ocean. Over millions of years, its front legs began to turn into fins. It completely lost its back legs, and its tail area grew into a large “flipper”. To breathe properly, its nose began to evolve from the front of his head up to the top and just turned into a hole. His skin changed, too, to include the special blubber that whales have to keep them
insulated. These, and many other changes, all by random chance, eventually turned the wolf-like dog into the whale we have today.
If you don’t like that idea, perhaps you might like the story that other evolutionists tell. They say that it wasn’t a wolf-like creature that turned into a whale, but a cow-like creature! So, it seems you have a choice!
Again, common sense will tell you that this is pure fantasy! And, it is NOT science to claim that any of this actually happened, and that the supposed processes can simply (and conveniently) be hidden behind the magic secrecy of millions of years of blind chance.