* Platypus
* Echidna
Marsupials
* Kangaroo
* Koala
* Wombat
* Tasmanian devil
* Opossum
Eutherians
* Human
* Dog
* Cat
* Horse
* Cow
* Pig
* Elephant
* Giraffe
* Lion
* Tiger
* Whale
* Dolphin
* Bat
This is a small sample of the thousands of mammals that exist on Earth. Mammals are found on all continents except Antarctica. They vary greatly in size, from the tiny shrew to the massive blue whale. Mammals are also incredibly diverse in their adaptations, reflecting their many different habitats and lifestyles.