What are Mammals?

A mammal is a name for a large group of animals. They are vertebrates, which means they have backbones, and, unlike reptiles and amphibians, they are warm-blooded. Mammals can also be recognized by their fur or hair, and by the fact that they feed their babies milk. Mammals are highly adaptable. They live on every continent and can live in grasslands, forests, oceans, polar regions, and deserts. Mammals can swim, hop, fly, run, and climb. There are more than 5,400 species of mammals alive on the earth today, and they range in size from the tiny bumblebee bat to the gigantic blue whale. Almost all mammals give birth to live young.

Some mammals, called marsupials, carry their babies in pouches. Only two kinds of mammals, the platypus and the echidna, lay eggs. Still, once they hatch, their babies drink milk, just like every other species of mammal. Because of this, mammal parents always take care of their offspring, some for a very short time – like the hooded seal, that nurses her pups for only four days – or for a very long time, like the orangutan, that nurses her baby for seven years. Mammals are warm-blooded, which means that they maintain constant internal body temperature. Keeping a stable body temperature takes a lot of energy, which means that mammals need to eat more than cold-blooded animals of similar size. However, mammals get that energy in many different ways. Some mammals are carnivores, eating only meat, some are herbivores, eating only plants, and some are omnivores, eating both plants and meat. You will probably recognize many of the types of mammals that are kept by humans. Some are kept on farms, to do work or provide food for people. Other mammals are very popular as pets. There are many more types of mammals that are happiest living in the wild. I hope you enjoyed learning about mammals today.