What is a fossil?

Fossil - are the remains, moulds, traces or impressions of prehistoric animals and plants found in the ground. The word comes from the Latin fodere, meaning "to dig", and originally meant any old curious object dug out of the earth. But since about the middle of the 16th Century, fossils have been regarded specifically as hard objects showing evidence of earlier forms of life often many millions of years old. There are many kinds of fossils. Some are footprints which strange prehistoric animals left behind in mud long since turned to rock. Others are stones which were once soft substances but still preserve the outlines of extinct plants or of seashells or of the bodies of animals. Sometimes even the bones of creatures have survived. The study of fossils which is called palaeontology has enabled scientists to fill many vital gaps in the history of the world and its inhabitants. For example, fossils have shown that rocks in great mountain ranges like the Alps or the Rocky Mountains were once below the surface of the sea. They have indicated that the United States and Europe were once covered by tropical forests. Also, they provide evidence of the common ancestry of animals which today differ widely in appearance. The subject can be rewarding hobby for amateurs. Many important contributions to the world's great collections have been made by people who looked for fossils in their spare time or even came across fossils by sheer accident.