The order Cetacea includes marine mammals, such as whales, dolphins, and porpoises. Fossil evidence suggests that the cetaceans share a common ancestor with land-dwelling mammals that began living in marine environments around 50 million years ago. Today, they are the mammals best adapted to aquatic life.
The order Cetacea includes marine mammals, such as whales, dolphins, and porpoises. Fossil evidence suggests that the cetaceans share a common ancestor with land-dwelling mammals that began living in marine environments around 50 million years ago. Today, they are the mammals best adapted to aquatic life.
