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Informationen zum Autor Ken Jennings is the New York Times bestselling author of Brainiac , Maphead , Because I Said So! , Planet Funny , and 100 Places to See After You Die . In 2020, he won the "Greatest of All Time" title on the quiz show Jeopardy! and later succeeded Alex Trebek as the show's host. He lives in Seattle with his family. Klappentext "With this book about dinosaurs, you'll become an expert and wow your friends and teachers with awesome prehistoric facts: Did you know that dinosaurs had large holes in their skulls to make their heads lighter? Or that the Tyrannosaurus Rex used its bad breath as a weapon? With great illustrations, cool trivia, and fun quizzes to test your knowledge, this junior genius guide will have you on your way to whiz-kid status in no time!"--Dinosaurs THE LAND BEFORE TIME History means “writing things down,” Junior Geniuses. If nobody records something happening, historians will never know about it. Keep that in mind when a grown-up promises to get you ice cream “later” or “some other time.” Get the promise in writing, or it didn’t happen! Human beings have been keeping written records for only five or six thousand years. Everything that happened before that is prehistoric—before history. We all know how time in recorded history works: We use a calendar. Days, months, years, centuries. Prehistory is different. The dinosaurs didn’t know or care if it was Tuesday or Friday or March or October. Prehistoric time uses a geologic time scale, which scientists calculate based on evidence they find in rocks. Comparing geologic time to a modern calendar is like comparing a dinosaur to a flea: It’s much, much bigger. Geologic time is measured in: AGES (long spans of time, hundreds of thousands of years) that combine to make up EPOCHS (really long spans of time, millions of years) that combine to make up PERIODS (incredibly long spans of time, tens of millions of years) that combine to make up ERAS (amazingly long spans of time, hundreds of millions of years) that combine to make up EONS (insanely long spans of time, billions of years) EARTH DAY The problem with geologic time is that it’s hard to wrap your brain around it. Think how long one minute can feel on the last day of school, or when there’s not a vacant stall in the restroom and you’re desperate. Now try to imagine one billion years’ worth of minutes. Good luck! But I have a trick that may help. Let’s compress the entire life of the earth down to one twenty-four-hour day. Blink your eyes once. BOOM, more than five thousand years just passed. All of human history, and you missed it. That’s how fast time is going on this scale. If the earth has been around for only one day, it was pretty busy. 12:00 A.M.: Earth forms out of dust and gas swirling around the sun. 4:00 A.M.: Life! Microscopic one-cell organisms appear in the oceans. 1:00 P.M.: Not until after lunch do these cells start to have a nucleus and little organs. 6:30 P.M.: Around dinner, tiny multi-cell creatures. 8:30 P.M.: The first plants—simple seaweed. 8:50 P.M.: Right around bedtime, animals f...
