Fossil
Although most fossils are formed from the hard parts of organisms, there are also indirect signs of prehistoric life. Examples such as a worm's trail or an animal's footprint are quite common. These are known as  trace fossils. Fossilized excrement, faeces or dung is known as a coprolite. A chemical trace of prehistoric organisms is called a chemofossil. Objects made by prehistoric people are called artifacts but these are not fossils.