by John Kricher, Professor of biology at Wheaton College in Norton, Massachusetts Dinosaurs-the word means "fearfully great reptile"-have been a source of fascination ever since their discovery in England early in the nineteenth century. Aside from birds, all dinosaurs have been extinct for 65 million years, yet, before then, they dominated Earth's terrestrial habitats for about 160 million years, far longer than primates, or humans, have been around. REUPLOAD NEEDED
PreSchool-Grade 2—A new cast of brightly colored dinosaurs appears in this charming back-to-school story. The text's easy rhyme and rhythm will be familiar to those who have read other books in this series, and Teague's charismatic and naughty dinosaurs will continue to delight readers with their antics and exuberance. The illustration accompanying "DOES A DINOSAUR YELL?" is sure to elicit smiles as an excited Herrerasaurus leaps out of his chair proudly holding up a newly lost tooth.
Discovery School - 100 Greatest Discoveries - Evolution
1. K-T Asteroid Theory of Dinosaur Extinction (1980) Walter Alvarez postulates that high levels of iridium found in rock core samples around the world provide evidence that an asteroid impact caused the extinction of dinosaurs. Iridium, a common mineral found in asteroids, was discovered in the clay layer at what is known as the K-T boundary. This layer, at 65 million years, lies between the rocks of the Cretaceous and the Tertiary periods and coincides with the mass extinction of dinosaurs.
2. First Dinosaur Fossils Identified (1820s – 1840s)
Danny's going to camp––and he's taking the dinosaur! First introduced in 1958 with Danny and the Dinosaur and the recent stars of Happy Birthday, Danny and the Dinosaur, this popular pair is together again in an adventure sure to please beginning readers and happy campers alike.