Basics p

■ ut a butterfly and a cricket side by side, and what do you

■ notice? Even though the size, shape, color, and sometimes J— the function of each part can be different, the basic body plan for both insects, and every other adult insect, is the same. (Immature insects can look very different than adult ones. See chapter 3,"Metamorphic Magic," for details.) They may seem similar to each other, but how do insects compare to you? Can they see better with those huge eyes? Are they really able to lift more, jump farther, and run faster than humans? Get ready to find out.

Insects are cold-blooded invertebrates (in-VUR-ta-brats). Invertebrates are all animals that do not have a backbone, including worms, clams, slugs, and insects. Instead of having bones to hold their bodies up, insects have exoskeletons. Exoskeletons are like miniature suits of armor. These hard shells protect insects' bodies and give a place for their muscles to attach. However, a solid, hard shell would be too hard to bend and move, so insect bodies are divided into three parts, and each part has smaller segments.

The three body parts are the head, thorax, and abdomen.

On its head, an insect usually has two sets ofjaws, two kinds of eyes, and one pair of antennae.

An insect's thorax has three segments. Each segment has a pair ofjointed legs, so an insect normally has six legs. Most insects also have one pair of wings attached to the middle segment, and another pair of wings attached to the back segment. But some insects have only one pair of wings, and a few have none at all.

The abdomen is the softest and most flexible part of an insect's body. It usually has between eight and eleven segments with tiny holes called spiracles on the side of each segment. These holes are how an insect breathes. The abdomen also holds an insect's stomach and other organs.

Almost 300,000 kinds of beetles have been identified so far, making them the largest group of animals on the earth.Their hard exoskeletons are one reason they have been so successful. How do exoskeletons help beetles and other insects survive? This activity will give you some ideas.


Spray bottle with water Paper towels 4 toilet paper tubes Watch or clock

Red food coloring Egg

wet paper towel

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