Insects are among the most diverse groups of animals on the planet, there are more than 5 million species and this represents more than half of all known living organisms. The life cycles of insects vary from one day to a few years.
Insects are mostly solitary, but some, such as certain bees, ants and termites, are social and live in large, well-organized colonies. lnsect pollinators are essential to the life-cycle of many flowering plants on which most organisms, including humans, are at least partly dependent.