The number of insects far surpasses the numbers of all other kinds of living things. Insects can be found in the fossil record back to Paleozoic times, some 350 million years ago. They are some of the oldest known forms of terrestrial animal life. Insects are necessary to life on planet Earth, for without them many plants and other animals would perish. One in every four animals on this planet is a beetle.
Insects are generally terrestrial as very few insects have invaded the sea.
The insects pre-empt every space on this world but for the deep oceans. Even in the frozen extremes of the Arctic and Antartica you will see some insects alive and active during the warmer months. Their ability to metamorphose, or change form, allows them to persist against extremes in climate and environment. Their fragile forms strive also in sheer numbers, where one female may produce thousands of eggs, allowing armies to capture Earth. Insects are ubiquitous, they are everywhere.