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This page explains why there are so many insects in the world.
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This page explains why there are so many insects in the world.
There are well over 1 million species of insects. They outnumber all other animals combined by more than 4 to 1. That means that if you counted up all the animals in the whole world, and then all the insects, there would be four times as many insects as animals. That's a lot of insects!
There are more different kinds of beetles than there are different kinds of flowers. They range in size from larger than the smallest mammals to small enough to crawl through the eye of a needle. They have been around since before dinosaurs roamed the earth.
What are the secrets for their success?
* they are small in size. That means that they can live in many more different kinds of places than larger animals. It also means that they only use a few resources so their food doesn't run out so quickly.
* they have a short life cycle. Because they only live for a short period of time, insects can live in temporary habitats such as water puddles and decaying organic matter. It also means they can adapt to changing conditions much more rapidly than other animals.
* they have LOTS of offspring. For example, an aphid has 50 offspring and it only lives for three weeks. Compare that with a human!
* they undergo complete metamorphosis. This means that they can live in two quite different places in one lifetime. (For example the dragonfly lives in the water for one part of its life, then flies in the air for the rest.)
* they have an exoskeleton. The exoskeleton is the 'shell' which protects insects from drying out in the sun and other damage.
* many of them can fly. Creatures who can fly are able to move to new habitats and food sources, and also escape from predators trying to eat them.
* diversification. Although they all have the same basic structure, each species of insect has adapted so that it is exactly suited to its own particular environment.