| A | B |
|---|
| mammary glands | secretes milk |
| monotreme | Duck-billed Platypus |
| marsupials | Australia |
| placenta | organ in womb |
| playing behavior | hunting and fighting skills |
| various kinds of teeth | eat a wide range of foods |
| high speed running | flexible hip and shoulder joints |
| endothermic | can remain active in cold temperatures |
| rodents | largest group of mammals |
| tusks | long modified teeth of Elephants |
| longer digestive tract | plant fiber is hard to digest |
| air sacs in lungs | increase surface area in lungs |
| bats | flying mammal |
| newborn marsupial | small and under developed |
| order Carnivora | lion, panda, and weasel |
| Therapsid | mammals evolved from this reptile |
