Insects

Insects are arthropods which first appeared about 380 mya. Insects are different from the other arthropods because they have only three pairs of legs and most insects have wings. Also, unlike most other arthropods, the insect's body is divided into three regions: the head, the thorax, and the abdomen.

Insects form the largest class of the arthropods, which is itself the largest animal phylum or tribe. Of all the animal species so far discovered, insects make up about five-sixths. As well as the roughly one million insect species known, there may be one to four million yet to be discovered.

Insects are divided into

Apterygota - primitive and wingless

Thysanura - bristletails, silverfish

Pterygota - more advanced winged or secondarily wingless

Coleoptera - beetles and weevils

Diptera - flies, midges, gnats,

Ephemeroptera - mosquito, mayflies

Heteroptera - bugs

Homoptera - aphids, leafhoppers, and cicadas

Hymenoptera - bees, wasps, and ants

Isoptera - termites

Lepidoptera - butterflies and moths

Neuroptera - lacewings

Odonata - dragonflies and damselflies

Orthoptera - grasshoppers, locusts, crickets, and katydids

Siphonaptera - fleas

Thysanoptera - thrips

Trichoptera - caddis flies

Another planet started to form but broke up into pieces because of the gravity of Jupiter. It formed a ring of small rocks where the planet should have been. We call them the asteroids.