|Did you know that spiders are not insects?|
Origins and Classification: Insect means "segmented" in Latin. There are about a million different types of insects and many more that have not been discovered yet. The biggest insect that ever lived was the ancient dragonfly called Meganeura. This predatory flying insect lived about 250 million years ago and had a wingspan of about 2 feet!
Insects are arthropods (a type of invertebrate, animals that lack a backbone). Insects evolved during the Silurian Period, 438 to 408 mya (long before the dinosaurs appeared). Insects don't have backbone.
Parts of an Insect: Insects have a head, an abdomen, and a thorax. Insects have an exoskeleton. Exoskeleton means that the bones and skeleton are outside the body. The exoskeleton is made up of a material that is very similar to our fingernails. An insect must also have 3 pairs (six) legs. A spider, for instance, has more than 6 legs and belongs to a different class called Arachnids. The legs (and wings, if present) of an insect are attached to its thorax. Insects breathe through holes called spiracles. Insects hatch from eggs.
Types of Insects: Most insects can fly. Examples of flying insects are butterflies, moths, dragonflies, flies, grasshoppers, and mosquitos. Some insects cannot fly. Examples of non-flying insects are spingtails, feas, lice, and ants.