| A | B |
|---|
| How many species of mammals are there? | 5,000 |
| What characteristics allowed early mammals to to hunt food and night? | They are endotherms |
| What size were the first mammals? | about the size of a mouse |
| How did the end of the dinosaur era allow mammals to spread out and live? | more food and land available |
| seven characteristics of mammals | making milk, diaphragm, endotherms, have hair, specialized teeth, sexual reproduction, and large brains |
| two benefits of mammals being endotherms | keeps them warm, and keeps body temperature constant |
| three ways mammals keep warm | hair, blubber, and endotherms |
| How long do newborns stay with parents | until grown |
| mammals all have | predators, need exercise, special features, need a certain amount of food |
| large brains help them to | learn, think, and respond quickly |
| What does diaphragm do? | helps them get air into lungs |
| What do mammals get to get energy from food | oxygen |
