Trace fossil topic

Trace fossils, also called ichnofossils (IPA: /ˈɪknoʊfɒsɨl/, Greek: ιχνος or ikhnos meaning "trace" or "track"), are geological records of biological activity. Trace fossils may be impressions made on the substrate by an organism: for example, burrows, borings (bioerosion), footprints and feeding marks, and root cavities. The term in its broadest sense also includes the remains of other organic material produced by an organism - for example coprolites (fossilized droppings) or chemical markers ... full article at wikipedia