Fossils Tell of Long Ago

What is a fossil?
Sometimes it' s the imprint of an ancient leaf in a rock. Sometimes it' s a woolly mammoth, frozen for thousands of years in the icy ground. Sometimes it' s the skeleton of a stegosaurus that has turned to stone.
A fossil is anything that has been preserved, one way or another, that tells about life on Earth. But you can make a fossil, too— something to be discovered a million years from now— and this book will tell you how.