They have long, sharp incisors on both the lower and upper jaw. Most rodents are herbivores. There are over 2000 species of rodents. They make up almost half of all the mammal species. They are found in all parts of the world except for Antarctica and New Zealand. .
Cetaceans have long torpedo-shaped bodies and tails that end in flukes.
They have an air or blow hole on the top of their head. Like most mammals, they give birth to live young and feed them milk. . Carnivora - the dog family, the cat family, bears, raccoons, pandas, sea lions, seals, walruses, bears, weasels, skunks, otters, badgers, civets, mongooses, hyenas Most carnivores are meat eaters. Their jaws can only move vertically, or up and down. Most carnivores have sharp side teeth, or canines, that help them sever meat. .