Climatic Control of Marine Trace Fossil Distribution

Marine trace fossils are not generally considered to be useful as climatic indicators, because of their usually long stratigraphic ranges, and because ichnotaxa may have been formed by a variety of different animals. However Ophiomorpha is today formed only in tropical/subtropical sediments. This appears to have been the case in older sediments, back at least to the early Caenozoic. The burrows of spatangoid echinoids forming Scolicia and Bichordites have a wider range (temperate to tropical). Together, and with regard to a few other trace fossils (Diplocraterion, Lingulichnus, Renichnus, and possibly Cruziana) these two conspicuous trace fossils offer small but significant climatic indications, if certain safeguards regarding identification are observed.