Book excerpt: Bugs make up more than 90 percent of all living things on Earth, but it can be difficult for people to remember that fact because of how tiny most are. Some bugs can only be viewed with the aid of a microscope. Others can be seen with the naked eye, but the details of their bodies must be magnified before they become visible. Through vivid full-color photographs and in-depth sidebars, this volume explores what exactly counts as a bug, why it is important to learn about them, and what they look like up close.