Trace fossils are the products of the activities of ancient organisms, including tracks, trails, burrows, borings, eggs and faecal remains. The importance of these fossils compared with body fossils (shells, bones) is that they provide the palaeontologist with evidence of how the ancient organism actually functioned, including activities such as locomotion, feeding, reproduction and social behaviour, for which no other data exist. They also provide the only evidence of the existence of soft-bodied organisms for which no other fossil material has survived.