If you could have been in North America or Europe twenty thousand years ago, you'd have thought you were at the North Pole! Much of the land was covered with a mountain of ice and snow. Many animals...
Elephants without trunks
Most scientists believe that 50 million years ago there were elephants living in swamps where Egypt is today. But they didn't look anything like elephants do now. The first elephants didn't have...
Horses without hoofs
> Eohippus > > \ Scientists say that if you could see the horses that lived 55 million years ago, you wouldn't know they were horses. They had toes on their feet instead of hoofs. They ate fruit...
Stories in stone
There were no people on the world when dinosaurs were alive. So how do we know about dinosaurs and other animals of long ago? Sometimes, when a dinosaur died, its body lay on muddy ground. The soft...
Tyrannosaurus the meat-eater
One of the most fierce-looking dinosaurs was Tyrannosaurus. Scientists can tell from its sharp teeth that it was a meat-eater. But they're not sure how it got its food. Some scientists think...
The first birds
The birds of today sing or whistle or screech. But the first birds may have hissed like snakes! They were more like reptiles than like birds. They were reptiles with wings and feathers. The first...
Flying reptiles
No reptile that lives today---snake, turtle, lizard, alligator, or crocodile---can fly. And no reptile of today has hair on its body. But scientists say that 150 million years ago there were many...
The biggest dinosaurs
You could have walked beneath an Apatosaurus and your head wouldn't even have touched its stomach. An Apatosaurus was as long as four big elephants standing in a line. The word Apatosaurus means...
Turtles and terrible lizards
According to most scientists, the first dinosaurs came into the world about 225 million years ago. And along with them came the first turtles. The word dinosaur means terrible lizard. But the first...
A 250-million-year-old puzzle
Scientists tell us that about 250 million years ago there lived a big reptile called Dimetrodon. It was about as long as a small automobile. It ate smaller reptiles. Dimetrodon had a big fin like a...
