Insects

In order to answer this question we must look at where insects fit in the animal kingdom. The animal kingdom is divided into several groups called phyla. An example of a phylum is the Chordata, which holds all the backboned animals. Insects belong to the phylum Arthropoda.

Arthropods are characterised by having the following features:

* a hard external skeleton (called a exoskeleton)
* a segmented body
* at least three pairs of jointed legs

The Arthropoda is divided into a number of classes. These include the:

* Crustacea (crabs, crayfish, prawns)
* Arachnida (spiders, mites, scorpions)
* Myriapoda (millipedes & centipedes)
* Insecta (insects)

The insects have proved to be the most successful arthropods. There are far more species in the class Insecta than in any other group of animals. These amazingly diverse animals have conquered all the environments on earth except for the frozen polar environments at the highest altitudes and in the immediate vicinity of active volcanoes.

Insects play a very important role in the web of life, in every environment. Some of their jobs include pollinating flowering plants, being a source of food for insectivorous animals and assisting in the decomposition of plants and animals.

Modern insect classification divides the Insecta into 29 orders, many of which have common names. Some of the more common orders are:

* Mantodea - praying mantids
* Blattodea - cockroaches
* Isoptera - termites
* Siphonaptera - fleas
* Odonata - dragonflies and damselflies
* Dermaptera - earwigs
* Diptera - flies
* Lepidoptera - butterflies and moths
* Orthoptera - grasshoppers, katydids, crickets
* Coleoptera - beetles
* Hymenoptera - wasps, bees, ants, sawflies
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