In Science we looked at Mammals

Mammals are warm-blooded vertebrate animals of a class that is distinguished by the possession of hair or fur, females that secrete milk for the nourishment of the young, and (typically) the birth of live young.

Mammals include humans and all other animals that are warm-bloodedvertebrates (vertebrates have backbones) with hair. They feed their young with milk and have a more well-developed brain than other types of animals.