Why are dinosaurs so popular with kids? Probably because they were so ugly, nasty, and often huge, and they lived a long time ago; so kids today don't have to worry about running into one of them on the street. Amazon lists 12,534 children's dinosaur books on their website. National Geographic has created one book in its LITTLE KIDS FIRST BIG BOOK series devoted to dinosaurs. This book includes eight small dinosaurs, 40 big ones, 72 giants, and 102 gigantic dinosaurs. The smallest is Microraptor. It weighed less than four pounds, had feathers and wings, but allegedly did not fly. Instead of flying it climbed trees and glided through the air. Just recently paleontologists have uncovered bones of the world's largest animal ever to have walked on Earth referred to as "the big one." A member of the newly discovered species of dinosaur called Titanosaur, it is thought to have stood up to seven stories tall and weighed up to 77 tons. Dinosaurs reigned on Earth from the Mesozoic Era about 250 million years ago until their extinction 65 million years ago. But undoubtedly just the mention of the word dinosaur will continue to create excitement in the hearts and minds of generations of kids for as long as the human race exists.