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Big Big Bugs

Bugs vs Insects
by Vicky Latz

Are you bugged by bugs?
Just what is a bug, anyway?

Some of us call any tiny, crawly thing a "bug." A spider might be a "bug," a butterfly might be a "bug," a mommy might call her baby a "cute little bug." Even the germs that make us sick are "bugs" and problems in computer programs are "bugs!"

Does the word "bug" have a special scientific meaning? Yes! There is one group of insects known to scientists as "bugs."

So how does something get to be called a true bug? First, of course, it has to be an insect. That means it has six legs and three body parts (a spider, remember, has eight legs and two body parts, so it can't be a true bug). Then, it has to be a certain type of insect. It must have a sharp mouth for poking a hole in its food to suck the juice. Butterflies and house flies can suck their food, but they cannot poke holes in things.

A true bug also has special wings. When the bug is resting, you will see only one pair of wings covering the bug's back. Near the head, these wings are thick and protective, but near the tail they are thin, just like the wings hidden underneath. (Just to make things tricky, some insects are called true bugs even though their wings are different. And some true bugs don't have wings at all!)

True bugs also grow differently from some other insects. Does a baby butterfly look like an adult butterfly? No! A baby butterfly is a caterpillar. The caterpillar has to change completely to become an adult butterfly. True bugs are different. A baby true bug looks like a small version of the adult true bug, but it doesn't have its wings yet. When insects grow this way, scientists call it "simple metamorphosis." The insects that change completely from baby to adult, such as butterflies and beetles, go through "complete metamorphosis."

True bugs are in the order Hemiptera. An order is a type of scientific grouping. You can learn more about how scientists group things (they call it classification or taxonomy) by checking out books in your library. The name of the order, "Hemiptera," means "half wing" to describe the wing that is half thick and half thin.

So which of the things we fondly call bugs are actually true bugs? Stink bugs, bed bugs, giant water bugs and milkweed bugs are just some of the true bugs. Come see the live insect zoo in the Big Big Bugs exhibit and look for our true bugs!

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