Can you imagine a bug the size of a small crocodile? How about one bigger than a large basketball player? As scary as it may seem, supersized, insect-like critters such as these roamed Earth long before humans. In this peek into prehistory, award-winning science writer Helaine Becker introduces seven of these megabugs, the ancestors of modern-day insects, spiders, crabs and other arthropods, which lived from 480 million to 47 million years ago...