parts of an insect

Insect Anatomy

Do insects have bones? Insects do not have a backbone like humans and many other animals do. In fact, insects do not have any bones; they have a hard exoskeleton instead. "Exo" means outside, so that means that the skeleton is on the outside of the insect's body instead of on the inside like in our bodies. Did you know that insects are related to crabs and lobsters, which also have exoskeletons?

Thinking Scientifically: Animals that have a backbone are called vertebrates - can you think of any vertebrates?. Any animals that do not have a backbone, like insects, are calledinvertebrates.

All insects have three main body parts: a head, thorax, and abdomen. It's important to know these parts in order. It helps to think of the thorax as being sandwiched in between the head (which is at the top just like your own head) and the abdomen (at the bottom).

Head: An insect has a small head that is a lot like your own head because it holds the insect's brain, eyes, and mouth. Insects also have special feelers called antennae that stick out of the top of their heads. They use their antennae to smell and feel because they do not have noses and hands like we do.

Thinking Scientifically: You may have heard the word antenna before, but have you ever heard anyone say antennae (pronounced: an-ten-I)? Did you know that "antennae" is just the plural form of the word "antenna"? When we say "antenna," we are talking about one and when we say "antennae," we are talking about two or more, just like when we say "shoe" we are talking one shoe, and when we say "shoes" we are talking about a pair of shoes.

Eyes: Insect eyes are much different from human eyes (called simple eyes). In fact, insects do not even see things the same way we do! They have two compound eyes with many different lenses to see out of instead of just one lens in each eye like we do. Each compound eye can have anywhere from 2 to 30,000 different surfaces that are very sensitive to light. Compound eyes cannot see very much detail or things that are far away. They can see extremely quick movements and things that are close to them, though. If insects did not have compound eyes, they would have a very difficult time surviving and finding food! Have you ever tried to swat a fly? What happened when you got close to it? It probably flew away the second you got close enough to swat it. That is because a fly's compound eyes bulge out of its head so it can see motion all around its body and see when you are coming closer to it.

Thinking Scientifically: Some insects, like grasshoppers, have compound eyes and normal eyes (called simple eyes)! With simple eyes, they can see a lot more detail and see things that are far away.

Click these links to see some close up pictures of compound eyes:

• Compound insect eye
  
• A dragonfly's compound eyes