What are five acquired traits of animals?

1. Mammals are warm-blooded vertebrates.

2. Give live birth

3. Females nurse their young with milk

4. Have skin, hair or fur.

5. Must breathe air using lungs and a respiratory system.

It must be noted that not all mammals give live birth. There is one sub-group of mammals known as monotremes. Monotremes are egg-laying mammals, which still fulfil all the other criteria listed above.