Animals live everywhere. They roam the land. They burrow in the ground. They swim in the sea. They fly through the air. They creep, they leap, they soar, and they dive. A very few—including corals and barnacles—stay in one place.
Animals come in all sizes. The biggest animals are whales, which can be 100 feet (30 meters) long. The smallest animals can only be seen through a microscope.
Zoologists (scientists who study animals) have found more than 2 million species (kinds) of animals. They think they have discovered only a small portion of all animals on Earth.
Maybe you help with chores at home. Maybe you play on a team. You know that a lot of work can get done if everyone shares part of the job. No creature knows this better than the ant. Ants live in groups called colonies. Every ant in a colony has a special job to do.
WHAT KINDS OF JOBS DO ANTS DO?
There are three kinds of ants in each colony: workers, queens, and males. Each kind of ant does a different job. Worker ants dig tunnels, raise young ants, collect food, and build and clean the nest.
It is nearly dark. From out of a cave, a black cloud swirls. Suddenly you realize that it is made up of thousands of bats.
Does this make you think of Halloween, or movies about Dracula? People often fear bats as “creatures of the night.” Yet these remarkable animals are helpful to us. They eat insect pests. They pollinate useful plants, as bees do. Their droppings, called guano, are used as fertilizer.
WHAT IS A BAT?
Bats are mammals. They are the only mammals that fly. There are nearly 1,000 species (kinds) of bats. They are found in all kinds of habitats. Bats live in tropical rain forests.
Suppose you want to dig some insects out of a tree trunk. Your fingers are too short to reach the bugs. What should you do? You could make a tool. You could find a stick and sharpen it to a point. You could use the point to spear the insects.
This is a good idea, but someone else thought of it first. Apes use sharp sticks to dig out insects. Apes are so smart that they have learned to make simple tools.
WHAT DO APES LOOK LIKE?
Apes are a kind of animal called a primate. Humans and monkeys are also primates.
Imagine sticking your nose in the air and sniffing the smell of a hamburger cooking a mile away. Some bears can do just that. Bears have a keen sense of smell. They use this sense to help them find food. Bears are meat eaters, or carnivores. But most bears also eat fruits, nuts, and other foods. Bears live in North America, South America, Europe, and Asia. They do not live in Africa, Australia, or Antarctica.
WHAT MAKES A BEAR A BEAR?
Bears are powerful animals with lots of thick fur and a short, stumpy tail. They have big heads with a long snout (nose and mouth) and small ears and eyes.