CONTENTS When Dinosaurs Ruled A Fossil Forms Dinosaur Fossils Whose Bones A Name at Last More Discoveries Paleontologists at Work A Fossil's Age Time to Eat What Did Dinosaurs Do Still Digging Glossary Index 4 6 8 12 16 18 20 22 24 26 28 30 31 WORDS IN THE GLOSSARY APPEAR IN BOLD TYPE THE FIRST TIME THEY ARE USED IN THE TEXT
WHEN DINOSAURS RULED Dinosaurs were amazing animals They could be bigger than a school bus or as small as a chicken They could be mean meat eaters or gentle plant eaters Dinosaurs ruled Earth for a long time But 66 million years ago almost all dinosaurs died out So how do we know so much about dinosaurs Fossils A fossil is what is left behind when something dies A A fossil may come from a plant or animal It may come from a bone footprint or egg Fossils can tell us when how and where dinosaurs lived long ago 4
WHEN DID DINOSAURS LIVE 66.4 MILLION YEARS AGO TERTIARY LATE cretaceous 975 MILLION YEARS AGO EARLY cretaceous 144 MILLION YEARS AGO JURASSIC 208 MILLION YEARS AGO TRIASSIC THIS CHART SHOWS SOME DIFFERENT KINDS OF DINOSAURS AND THE TIME PERIODS IN WHICH THEY LIVED 245 MILLION YEARS AGO Explore More ARCHOSAURS WERE PART OF A LARGE GROUP OF REPTILES THAT INCLUDED DINOSAURS MOST ARCHOSAURS DIED OUT BUT TWO EVOLVED AND STILL LIVE TODAY BIRDS AND CROCODILES 5
