For over a century the blue whales almost entered mass extinction when they were being hunted until they became a protected animal.
Hippos likely evolved from a group of anthracotheres about 15 million years ago, the first whales evolved over 50 million years ago, and the ancestor of both these groups was terrestrial. These first whales, such as Pakicetus, were typical land animals. They had long skulls and large carnivorous teeth. The blue whales used to walk on land with most of the other sean animals known today. The whale has a “leg” bone near the back of its body called the vestigial hip bones. Through evolution the whales have slowly gone into the water and did not need their legs so over time they went