Can You Tell Me Some Basic Facts About Arthropods?

The phylum Arthropoda (arthro = joint, poda = foot) is the largest phylum in the animal kingdom. It includes about 75% of all known animal species. We know of 900 000 species of arthropods. Many more have yet to be discovered and studied.

The oldest fossil insect is a 390-million year old bristletail found in Quebec in Canada. Some insects have 4 000 individual muscles, which is amazing considering that humans have less than 500. The female of most species of insect is larger than the male.

An insect's worst enemies are other insects - millions of insects eat animals instead of plants and most feed on other insects. Around 200 million insects and mites can live in the soil of an acre of rich pasture land. Most spiders have eight eyes, some 6. But there are spiders with no eyes, 2, 4 and up to even 12 eyes.