Mammals are warm-blooded, which means their bodies make their own heat and stay at a steady temperature regardless of the weather.

Reptiles are cold-blooded, meaning their body temperature changes with their surroundings. They often bask in the sun to warm up.

An eagle uses its wings to fly high in the sky. Wings are one of the key features that all birds have, even if they cannot all fly.

A turtle carries a hard shell on its back for protection. The shell is part of the turtle's skeleton and helps keep it safe.

Insects have six legs and three body parts: the head, thorax, and abdomen. Having six legs is a defining feature of all insects.

A salmon lives in water and breathes with gills. Gills filter oxygen from the water so the fish can breathe.

Baby mammals drink milk from their mother. Producing milk to feed young is one of the traits that defines mammals.

A lizard is a reptile because it has dry scales, is cold-blooded, and lays eggs. Reptiles include snakes, turtles, and crocodiles.

Frogs live near water because they are amphibians. Amphibians need water to lay their eggs and to keep their skin moist.

Bear → mammal because it has fur and feeds its cubs milk. Penguin → bird because it has feathers and lays eggs. Gecko → reptile because it has dry scales and is cold-blooded. Trout → fish because it lives in water and breathes with gills.