I thought the hippo was related to the horse amd the rhino was related to the pig.
You thought wrong.
It was commonly thought that hippos were related to pigs. Recently DNA has proved that Hippos are related to dolphins and whales which is why they can submerge themselves in water for long periods of time.
It was commonly thought that hippos were related to pigs. Recently DNA has proved that Hippos are related to dolphins and whales which is why they can submerge themselves in water for long periods of time.