Trace Fossil

trace fossil [′trās ‚fäs·əl]

(geology)

A trail, track, or burrow made by an animal and found in ancient sediments such as sandstone, shale, or limestone. Also known as ichnofossil.

---

Trace Fossil 

a manifestation of the vital activity of an extinct organism. Some paleontologists believe that trace fossils include only the traces (ichnolites) left by animals as a result of locomotion on land or the bottom of a body of water, as well as various trails and burrows in loose sediments and rocks and borings into mollusk shells. Others more broadly interpret the concept to include various evidences of the physiological function of organisms. For example, reproduction in ancient animals is studied by the remains of birds’ eggs and fish roe, and nutrition by the remains of gastroliths and by excrements and food in the stomach. Traces of injuries and illnesses and structures inhabited by extinct animals are also called trace fossils.

Trace fossils are found in the deposits of all geological systems, beginning with the Precambrian. They provide clues to the existence in the geological past of organisms of which nothing has been preserved except the trace fossils and give some idea of the way of life of extinct animals. The branch of biology that studies trace fossils in the narrow sense is called ichnology (or palichnology). Assemblages of trace fossils found in deposits are called ichnocoenoses.

REFERENCES

Vialov, O. S. “Klassifikatsiia iskopaemykh sledov zhizni.” In Paleontologiia. Moscow, 1972. (Mezhdunarodnyi geologicheskii kongress: XXIVsessiia: Doklady sovetskikh geologov: Problema 7.)
Gekker, R. F. “Sovremennoe sostoianie izucheniia sledov vymerskikh bespozvonochnykh (paleoikhnologiia bespozvonochnykh).” In Voprosy zakonomernostei i form razvitiia organicheskogo mira: Trudy VII sessii Vses. paleontologicheskogo ob-va. Moscow, 1964.
Abel, O. Vorzeitliche Lebensspuren. Jena, 1935.

R. F. GEKKER