WHAT IS PALEONTOLOGY AND GEOLOGIC TIME?
Paleontology is the study of ancient life (life that is typically older than 10,000 years). Paleontologists study fossils and the rock layers in which they are found. Fossils are the remains or traces of ancient life. A fossil can be a seed from an ancient plant, the bone of an animal, or even prehistoric footprints or feces. Fossils are most commonly preserved in sedimentary rocks (rocks that are formed from the eroded grains of older rocks or minerals). Some of the most common sedimentary rocks are sandstone, shale, and limestone. In the Fossil or Not? component, visitors view a variety of fossils and non-fossils and see if they can determine the difference. Geologic time refers to the length of time the earth has existed. It is a scale used internationally as a reference to certain key events in the history of the planet. Scientists currently believe that the earth formed between 4.5 and 5 billion years ago. As more knowledge is gained, the story of how the earth actually formed is
