Mammals
Mammals are warm-blooded animals with backbones, and most of them have fur or hair. One of their coolest features? They nurse their babies with milk produced by the mother. Mammals come in all shapes and sizes—from tiny bats to massive whales—and they live just about everywhere: in oceans, forests, deserts, and even your backyard. Whether it’s a playful dolphin or a sleepy bear, mammals are some of the most familiar and fascinating animals on Earth!