Megalodon sharks are extinct, while blue whales still exist.
Megalodon lived from the late Miocene 6.5438+0.5 million years ago to the early Pleistocene 2.6 million years ago, and it was the top marine predator in its life.
The blue whale is the first generation of mammals. They have lived on the earth for 50 million years. The first blue whales were middle-clawed animals that lived on land. After a long time, they changed from terrestrial to amphibious, and then became modern whales and dolphins.