SECOND CLASS SCOUT

Kinds of Wild Animals

Biologists divide all animals into large groups - vertebrates and invertebrates.

Vertebrates have backbones, invertebrates do not.

There are five classes of vertebrates, each based on physical similarities:

Birds

Warm-blooded animals with wings and feathers are birds. They hatch their young frmo eggs.

Mammals

Deer, bears, foxes, squirrels, moles, and other mammals are warm-blooded vertebrates that have some kind of hair. They nurse their babies with milk.

Reptiles

Snakes, alligators, crocodiles, lizards, and turtles are all reptiles - cold-blooded, air-breathing animals with backbones. Some move on short legs while others crawl on their bellies. Reptiles are covered with scales or bony plates.

Fish

Fish are cold blooded, live in water, and breathe through gills. Their bodies are covered with scales.

Amphibians

Frogs, toads, newts, salamanders, and other amphibians start life in the water as gilled aquatic larvae hatched from eggs. Adult amphibians breathe air and generally live on land.

Invertebrates greatly outnumber vertebrates on our planet, and can be divided into many more groups. The largest invertebrate group is made up of arthropods - insects, arachnids, and crustaceans. The mollusk group, second in size to the arthropod group, includes snails, clams, oysters, mussels, and squids.