What Makes An Insect An Insect? 4 Common Characteristics

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An Ant is a common insect that can be found throughout the world.

Every insect in the world has 4 common characteristics.  These traits are what make an insect an insect and not a spider, mammal, or bird.

There are so many different kinds of tiny bugs in the world.  They come in various shapes, sizes, colors and live everywhere imaginable.  They live underground, in the forest, on mountaintops, or underwater.  Some fly, others crawl, and others do both.  Despite how different they may appear, every single insect shares a number of common traits that make them an insect.

insectEvery Single Insect Has These 4 Characteristics

In general, what makes an insect an insect?  All insects have the following in common:

Exoskeleton – Insects all have an exoskeleton.  This is a hard shell like covering on the outside of its body.

Three Part Body – The body itself is composed of three parts: head, thorax, and abdomen.

Six Legs – They have six legs.

One Pair Of Antennae – They have one pair of antennae.

Not All Tiny Creatures Are Insects

Most people think of all tiny little creatures they see as bugs.  Most of the time when people use the term bug it is in a general sense and refers to a broad range of tiny animals, including insects.  However, insects are certain types of those little creatures.  There are some little creatures that are the size of bugs, but are not actually insects because they do not have all of these characteristics.

Additionally, there are some types of insects that are called ‘true bugs.’  True bugs are an order of insects that comprise thousands of species, including aphids, shield bugs, and cicadas.

One of the tiny creatures that does not have all the characteristics is an earthworm.  An earthworm is an invertebrate (meaning that it has no backbone), but it does not have the characteristics of insects.  Read here for information about what happens if you cut a worm in two.

Here is  little test – are these insects or not?

SPIDER?

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An easy one to start.  Is a spider (black widow) an insect?

NO.  Spiders have eight legs and so are not insects.

GRASSHOPPER?

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YES.  Grasshoppers are insects.

BUTTERFLY?

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YES.

PILL BUG OR SOW BUG?

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NO.  Pill bugs have more than six legs.