Taphonomy is a multidisciplinary, multitasking body of knowledge that studies the processes affecting organic remains after deaththat is, the transition of these remains from the biosphere into the lithosphere. Taphonomic studies are key to paleobiology, paleontology, archaeology, geology, and geography, among other disciplines, as they impinge directly on our capacity to reconstruct paleoenvironments and past biotas. They do so by understanding the postmortem processes on biological materials and how they affect the fossil recordbroadly defined as the set of nonliving remains and traces of organismsand the information therein.

The term taphonomy, from the Greek taphos and nomos (the laws of burial), was coined by Ivan Efremov in 1940, although such inquiries had been carried out well before, notably by German paleontologists in the late 19th and early 20th centuries. These researchers focused primarily on paleoenvironmental reconstruction, while Efremov and others emphasized information loss and biases introduced in the fossil record. Other researchers, especially after the input by Anna Behrensmeyer, Susan Kidwell, and Diane Gifford, have focused on the positive contributions of taphonomy as well. These emphasize the preservation of the fossil record and the paleoecological and paleobiological information contained in the signatures of the processes that have affected it through time. Moreover, all the recycling pathways of biologically derived materials are informative to taphonomic enquiry.

The processes affecting organic remains from death to final burial, such as carnivore scavenging of vertebrate carcasses, are different from those occurring from final burial until recovery, as is the case with mineral replacement in different organic remains. The former are known as biostratinomy and the latter, as diagenesis, and both constitute taphonomy. On infrequent occasions, as in the case of severe floods and catastrophic death, rapid burial of organisms lead to large concentrations of exceptionally well-preserved fossils, known as fossil lagersttten.

Taphonomists study both direct and indirect evidencethat is, not only the organic remains themselves but also the traces of different organisms, such as the tooth marks of a predator on bones or a leaf imprint on a sedimentary matrix. These traces or signatures of activity by an organism are also known as ichnofossils and commonly inform us of the interactions with its environment. Finally, they study the geological context where the fossils and traces are deposited as well.

To understand and interpret all these lines of evidence, taphonomic principles are needed. As in other historical sciences, the most powerful strategy for doing so is actualismthat is, the study of contemporary, observable taphonomic processes producing effects analogous to those observed in the fossil record, and their causes. This strategy has been key in taphonomy since the German Aktuopalontologie (invertebrate) program in the early 20th century. Observing present-day processes and their contexts links causes and effects, thereby generating models that can be applied to the fossil record by analogy. In some cases, experiments can help understand the effects of some processes as well. Such studies require assuming that the processes operating in the past are essentially the same as those operating in the present, although their rates and configurations and their interactions may well have changed through time. This methodological assumption is called uniformitarianism.

Another important strategy is the comparative method, namely, the comparison of different fossil records, which allows considering processes at a larger scale of operation. Deductions from general models and strong links among different lines of evidence complement both strategies.

All these approaches allow reconstructing and interpreting the taphonomic histories of different fossils. It should be noted that each specimenthat is, an individual organic remain or tracehas its own history, which can differ from that of other specimens in the same assemblage. Some variables, such as morphological and qualitative ones (e.g., chemical alterations), are monitored on each specimen. Other variables, though, such as the quantitative and contextual ones (e.g., the spatial relationships among different specimens), can only be assessed at the assemblage level. Therefore, analysis always begins at the specimen level, while fossil assemblages, with their specific propertiessuch as specimen arrangement, statistical trends in specimen properties, and the paleoecological information they bearturn out to be the main unit of analysis and comparison. The geological context bearing the assemblages provides important, independent evidence as well that helps infer the taphonomic history of the fossil

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record, for instance, by shedding light on the accumulation processes that concentrated the fossils under study. All these lines of evidence can be integrated at the landscape level so as to interpret taphonomic patterns and processes at a regional scale.

A more general approach considers taphonomic modes, which encompass fossil records resulting from similar processes (physical, chemical, and biological), involving similar preservational contexts. Hence, different taphonomic modes are characterized by different biases. Changes through time in taphonomic modes would thus generate megabiases.

One particular taphonomic mode is archaeological accumulations, where humans are the main taphonomic agents. These can be isolated or can even modify whole landscapes, as in the case of shellmound concentrations in coastal Brazil and Uruguay. Humans can not only be taphonomic agents but also the subject of taphonomic processes, as has been studied by forensics and paleoanthropology, two disciplines where taphonomy is also central.

It is the multidisciplinary nature of taphonomy, whereby very different questions are posed at varying scales, that contributes to the richness of this research field.

A. Sebastin Muoz and Mariana Mondini

Allison, P. A. , ed. , & Briggs, D. (Eds.). (1991). Taphonomy: Releasing the data locked in the fossil record. New York: Plenum Press.

Further Readings

Behrensmeyer, A. K. , Kidwell, S. M. , and Gastaldo, R. A. Taphonomy and paleobiology. In D. G. Erwin & S. L. Wing (Eds.) Deep time: Paleobiology's perspective. Paleobiology vol. 26 no. (Suppl. to No. 4) pp. 103147. (2001).

Gifford, D. P. (1981). Taphonomy and paleoecology: A critical review of archaeology's sister disciplines. In M. B. Schiffer (Ed.), Advances in archaeological method and theory (Vol. 4 , pp. pp. 365438). New York: Academic Press.

Lyman, R. L. (1994). Vertebrate taphonomy. Cambridge, UK: Cambridge University Press.

Entry Citation:

Muoz, A. Sebastin, and Mariana Mondini. "Taphonomy." Encyclopedia of Geography. 2010. SAGE Publications. 5 Oct. 2010. .

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