Insects Background Information for Teachers, Parents and Caregivers
This page provides information to support educators and families in teaching K-3 students about insects. It is designed to complement the Insects topic page on BrainPOP Jr.
Help children learn about the world around them and understand how living things are connected. This movie explores insects—their anatomy, behavior, life cycle, and their vital roles in food webs and food chains. The movie also explains how insects are not pests, but important organisms that many living things—including humans—rely on to survive. The insects movie builds upon concepts introduced in the Food Chain movie, as well as the Butterflies and Camouflage movies. You may also want to check out the Classifying Animals movie before screening this one.
Review with children that an invertebrate is an animal that has no spine, or backbone. Brainstorm different invertebrates such as slugs, worms, spiders, flies, bees, squid, crabs, lobsters, seahorses, sea anemone, and coral. What do these animals have in common? How are they alike and different? Children will see that invertebrates cover a wide range of habitats. Explain that most of the world’s animal species are invertebrates. Scientists have found over 1.3 million species of invertebrates and only about 64,000 species of vertebrates. About 1 million of those invertebrate species are insects. In other words, most of the animals on our planet are insects! You may want to explore these numbers using a pie chart or other graph.
Describe the main characteristics of insects. They have three body parts: head, thorax, and abdomen. The head contains the mouth, eyes, and a pair of antennae. The antennae help the animal sense the world around them—they pick up scents and detect movement and changes. The antennae on insects differ as widely as the insects themselves. Some look feathery while others are short and segmented. Observe different insect antennae by visiting the library, a local museum, or researching on the Internet.
The head also contains the eyes. Explain that insects have compound eyes, which look a lot different from our own eyes. Compound eyes are made up of tiny sensory units that point in different directions. This allows the insect to have a greater field of vision and see more of the environment at once. Contrary to popular belief, insects do not see the world as a kaleidoscope. Their brains process information from each sensory unit in the eye to create one image.
The insect’s thorax is the middle part of the body. This is where two pairs of jointed legs attach to the body. If the insect has wings, then those attach to the thorax as well. Brainstorm different winged and wingless insects with children. Some beetles may not look like they have wings, but actually do, such as cockroaches and ladybugs.
The abdomen is the lower part of the insect’s body and it contains the digestive system. Remind children that the digestive system is in charge of breaking down food and taking in nutrients for the whole body. It is important to know that insects have exoskeletons, meaning the skeletons are on the outside of their bodies. Children who have observes an insect will recall the hard covering.
Insects can be found on every continent on the planet, including Antarctica! They can be found in the frozen tundra or on ocean shores. Insects have adapted to their environments to survive. Brainstorm ways insects stay safe from their predators. Some insects, such as the gypsy moth, use camouflage. Their bodies look exactly like tree bark! Other insects, such as the stinkbug, release a foul odor to ward off enemies. Insects such as the milkweed grasshopper release a poisonous substance that predators want to avoid. Wasps and bees have stingers, and ants have sharp, powerful mandibles that allow them not only to cut leaves, but attack enemies. Monarch butterflies are poisonous to predators (or at least foul-tasting) and so viceroy butterflies mimic the color and patterns of Monarch wings to stay safe. Research different insects that are in your area with children. How do these animals survive?
Remind children that insects go through metamorphosis as they turn into adults. Some insects go through incomplete metamorphosis. For example, a beetle will hatch from an egg as a nymph. As the nymph grows, it must molt and shed its exoskeleton to make room for a bigger one. A nymph might molt 4 to 40 times in its lifetime before it turns into an adult. Other insects, such as butterflies, will go through complete metamorphosis. A caterpillar, or larva, will hatch from an egg. The larva eats and grows and eventually enters the pupa stage. A chrysalis forms and inside the pupa turns into a mature butterfly. All insects go through metamorphosis, and many scientists agree that all insects hatch from eggs.
Help children understand that while many people think of insects as pests, insects actually serve important roles in our environment. Insects such as bees play important roles in pollinating flowers. Many of our fruits and vegetables rely on bees for pollination. Some burrowing insects help turn the soil to keep it fertile for our plants, while others help break down dead plant matter so nutrients return to the soil. Children may already know that birds and bats help control insect populations for farmers. Explain that insects help control other insect populations, too! Aphids might harm crops, but ladybugs eat aphids. So many farmers or gardeners will lure ladybugs to help keep their crops healthy.
Insects play important roles in many food chains and food webs. A myriad of animals feed on insects, including mice, snakes, lizards, birds, raccoons, and even bears. Since insects are able to reproduce rapidly, they offer a sustainable source of food for many animals. In addition, insects give us food and things people use every day. Silkworms give us silk and bees give us wax and honey. What else do insects give us? Discuss with children.
Explore the weird and wonderful world of insects with children. Help them understand that insects are not just animals that gross us out or scare us. They serve a critical role in our ecosystem!