The Sun Insects Insects Bugs and critters, but more specifically called insects, have been around for more than 350 million years. During this time, they have developed numerous physical features that allow them to survive on almost every part of the globe. Although these critters are quite diverse in their appearances, they all share several key traits. These characteristics distinguish an insect from other bugs such as spiders and centipedes.
Insects begin their lives as eggs.
From there, some kinds progress through complete metamorphosis in which they change into a larva and then into a pupa. At these times in their lives, insects usually look strikingly different from the adults that they will finally become. The worm-like larvae develop small wings and eyes, and they shed their outer coating in a process called molting. Molting allows the insect to grow in size. Insects usually spend their pupal stage of development inside of a sac-like cocoon, where they release chemicals that activate certain cells to grow and to divide.