Taphonomy

Taphonomy is the study of decaying organisms over time and how they may become fossilized. The term taphonomy (from the Greek taphos, τάφος meaning "burial", and nomos, νόμος meaning "law") was introduced to paleontology in 1940 by Russian scientist Ivan Efremov to describe the study of the transition of remains, parts, or products of organisms, from the biosphere, to the lithosphere, i.e. the creation of fossil assemblages.

Taphonomists study such phenomena as biostratinomy, decomposition, diagenesis, and encrustation and bioerosion by sclerobionts. (Sclerobionts are organisms which dwell on hard substrates such as shells or rocks.)

One motivation behind taphonomy is to better understand biases present in the fossil record. Fossils are ubiquitous in sedimentary rocks, yet paleontologists cannot draw the most accurate conclusions about the lives and ecology of the fossilized organisms without knowing about the processes involved in their fossilization. For example, if a fossil assemblage contains more of one type of fossil than another, one can infer either that the organism was present in greater numbers, or that its remains were more resistant to decomposition.

During the late twentieth century, taphonomic data began to be applied to other paleontological subfields such as paleobiology, paleoceanography, ichnology (the study of trace fossils) and biostratigraphy. By coming to understand the oceanographic and ethological implications of observed taphonomic patterns, paleontologists have been able to provide new and meaningful interpretations and correlations that would have otherwise remained obscure in the fossil record.

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