Rise and fall of the dinosaurs

	Rise and fall of the dinosaurs contents T. rex would not have recognised the world that the first dinosaurs lived in. In this series of articles, Dr Jo Wright explores how the dinosaurs evolved as the world around them changed. New blood When dinosaurs first appeared the world was very different. There were no mammals, no birds and no lizards. But there were some lizard-like reptiles. Time of the titans In the Early Jurassic, dinosaurs started getting larger. Diplodocus was over 30 metres long - but even he wasn't safe from predators. A cruel sea While dinosaurs dominated the land, huge marine reptiles ruled the water. Ichthyosaurs looked very like dolphins - but they weren't the top predators of the Jurassic seas. Giant of the skies The largest animals ever to fly were pterosaurs. But during their reign, birds as we know them were also beginning to appear. Spirits of the ice forest There's considerable evidence that dinosaurs once lived at polar latitudes. How did they survive the cold? Land of the giants Argentinosaurus was the largest dinosaur ever - 35 metres long, and up to a hundred tonnes in weight. The giant claw 75 million years ago the Mongolian desert was home to dinosaurs of all shapes and sizes - including one with the largest claw of all time. Death of a dynasty Why the dinosaurs died out is one of the most frequently asked questions of dinosaur experts. Will we ever know the answer?