Taphonomy

Taphonomy KAREN B. BORRAZZO Instituto Multidisciplinario de Historia y Ciencias Humanas, CONICET, Argentina; Universidad de Buenos Aires, Argentina The term taphonomy (from the Greek words taphos meaning “burial” and nomos meaning “laws”) was originally selected by Russian scientist Ivan A. Efremov (1940) to name a specialization within paleontological research devoted to the study of the transition of animal remains from the biosphere into the lithosphere. Thus, it was conceived as the detailed study of the processes and transformations undergone by an organism from its death to the fossilization of its remains. Although this definition of taphonomy primarily dealt with Efremov’s interest in the passage of terrestrial vertebrate remains from the biosphere into the lithosphere, subsequent uses of this approach to study different fossil assemblages broadened its application to other organic remains (plants, molluscs) and beyond the paleontological record. Indeed, it was within the field of archaeofaunal studies (see zooarchaeology) that most nonpaleontological theoretical and methodological contributions to taphonomic research took place. In recent decades, archaeologists began to develop and systematize taphonomic frameworks to study nonorganic materials, such as lithic artifacts, on a regular basis as well (Hiscock 1985). Although not without dissent, archaeological practitioners of bone taphonomy support the current expansion of taphonomic perspectives towards the analysis of other materials of the archaeological record (see archaeological record). Taphonomy can be broadly defined today as the theoretical and methodological scientific approach devoted to understanding the post-depositional (taphonomic) history of any fossil record (paleontological, archaeological, forensic, or other), considering all its components, their spatial arrangement, and context (Domínguez-Rodrigo, Fernández-López, and Alcalá 2011). It seeks to identify the mechanisms and the sequence of events involved in the formation of any assemblage and its sedimentary matrix. Furthermore, it studies the processes of preservation and how they affect information in the fossil record (Behrensmeyer and Kidwell 1985). Thus, taphonomy addresses the constant tensions between preservational and destructive media through the study of the record of these tensions on different materials (Borrero 2014a). There is increasing recognition of the fact that every fossil record has been affected by taphonomic processes and that the impact of those processes needs to be properly evaluated in order to proceed with paleobiological or behavioral interpretation (see interpretation). Indeed, a taphonomic diagnosis is key to assessing bias and adjusting research questions to the characteristics and scale of the record under study. Or the other way around: if a taphonomic research is conducted at the landscape or regional scale, it guarantees the selection of the more adequate loci to answer specific research questions (Borrero 2014b; Burger, Todd, and Burnett 2008). Thus, from a taphonomic perspective, the transformations undergone by material remains within the process of fossilization are not only biased but also an additional source of information. Certainly, the widespread integration of taphonomic approaches in archaeological studies proved that most archaeological sites are better explained as cumulative, time-averaging, and dynamic phenomena (i.e., palimpsests exhibiting differential integrity, resolution, and preservation) rather than static well-preserved “living floors.” Several basic concepts are the backbone of taphonomic approaches. Agents are the sources of energy (e.g., wind) that trigger different processes (e.g., transport). The latter modify the properties of material remains; such changes are known as taphonomic effects. Finally, taphonomic history is the sequence or order in which agents and processes acted upon an assemblage (Gifford 1981; Lyman 1994). The Encyclopedia of Archaeological Sciences. Edited by Sandra L. López Varela. © 2018 John Wiley & Sons, Inc. Published 2018 by John Wiley & Sons, Inc. DOI: 10.1002/9781119188230.saseas0568 2 TA P H O N O M Y Each taphonomic agent (e.g., wind, water, gravity, fauna, vegetation) originates manifold taphonomic processes (e.g., transport, sandblasting, dissolution, trampling, gnawing), which comprise physical, chemical, or biological mechanisms. These mechanisms impinge on the original attributes of remains. Within taphonomic studies, processes and their effects are separated into two general realms according to the context—before or after burial—in which they take place. Biostratinomy is the segment of taphonomic history that spans between the death of an organism and the final burial of its remains, while fossil diagenesis (see diagenesis of bone) comprises the modifications occurring on remains after burial. Thus, since weathering (the physical and chemical decay of bone components) mainly occurs in subaerial contexts, it falls within the realm of biostratinomy, while bone mineralization and deformation are primarily diagenetic processes. More generally, taphonomic effects on any fossil remain can be classified into two basic categories: morphological and distributional alterations. The former includes changes in the aspect, texture, shape, size, and so on of elements. The meaning of morphological effects in terms of formational history can be evaluated at the individual level (e.g., on an isolated specimen), although an assemblage approach is more informative. Examples of morphological modifications on different raw materials (bone, lithic, ceramic, wood) include polish, abrasion, fractures, tooth marks, cracking, root etching, weathering rinds, and coatings. On the other hand, distributional modifications transform the spatial arrangement of fossil remains. These phenomena encompass the movement of specimens and changes in their position—such as vertical and horizontal displacements, changes in the axial orientation, inclination, and inversion. Burial also modifies the distributional properties of the assemblages. Unlike morphological modifications, the assessment of taphonomic spatial changes is only feasible at the assemblage level. The study of taphonomic effects is essential for assessing the existence of taphonomic bias in fossil assemblages and identifying its possible sources. Several factors determine the occurrence and characteristics of taphonomic effects. First, each environmental, sedimentary context exposes assemblages to differential conditions (i.e., potential taphonomic agents and processes). Therefore, researchers need to build any taphonomic study on a case-specific basis: identify the past and present agents that were locally available, the energy and magnitude of the processes they triggered, their signatures on different materials, and so on. Second, taphonomic effects vary according to the intrinsic properties of each organic or nonorganic element (i.e., physical and chemical attributes of remains). Thus, material-specific frames of reference are required to undertake the taphonomic study of every component of a multifabric record, as is the case of many archaeological assemblages (bones and ivory (see bones and ivory), lithic, ceramic, metal, wood, etc.). Third, it is expected that the intensity and extension of taphonomic effects vary according to the duration of the process. Furthermore, given the sequential and cumulative nature of taphonomic effects, earlier processes in the taphonomic history of an assemblage may facilitate the subsequent transformations of remains by a different mechanism. Taphonomic methods integrate the principles, knowledge, and case studies from natural sciences (biology, physics, chemistry, geology) with observations on the fossil record itself. Actualism is also central to most taphonomic research. Uniformitarism principles, modern experiments (see experiment in archaeology), and naturalistic observations provide jointly with natural sciences the frame of reference to assess taphonomically the patterns exhibited by the fossil record (e.g., Weigelt [1927] 1989). Hypothesis testing (see hypothesis testing) and the integration of data provided by other lines of evidence are common procedures in taphonomic research, since more than one agent and/or process produces the same trace or effect on material remains (equifinality). Therefore, competitive explanations are evaluated against a corpus of actualistic and fossil data to account for fossil trends. The general goals of taphonomic studies within the realms of archaeological research have mostly focused on: • • assessing differential attrition to reconstruct the original content and patterns of material remains (see deterioration); establishing agents of accumulation and modification as well as the sources of bias; TA P H O N O M Y detecting and describing common taphonomic trends at different spatial scales, whether to recognize background noise (e.g., the natural deposition of bones or taphonomic “bone rain,” geofacts or other lithic pseudoartifacts) or to identify sites or spaces that share their taphonomic properties (isotaphonomy); characterizing the taphonomic history of a fossil assemblage, that is, detailing the circumstances (sequence of events) under which the assemblage existed through time. 3 SEE ALSO: Archaeoentomology; Archaeometry; Charcoal and Wood Analysis; Conservation; Environmental Archaeology; Formation Processes; Geoarchaeology; Lithics Data Quantification; Marine Molluscs; Paleoethnobotany; Palynology Borrero, Luis Alberto. 2014a. “Multi-Service Taphonomy: Shells, Garbage, and Floating Palimpsests.” In Taphonomic Approaches to the Archaeological Record, edited by Karen Borrazzo and Celeste Weitzel, 13–20. Intersecciones en Antropología 15 (suppl. 1). Buenos Aires: Facultad de Ciencias Sociales–UNICEN. Borrero, Luis Alberto. 2014b. “Regional Taphonomy.” In Encyclopedia of Global Archaeology, edited by Claire Smith, 7232–35. New York: Springer. Burger, Oskar, Lawrence Todd, and Paul Burnett. 2008. “The Behavior of Surface Artifacts: Building a Landscape Taphonomy on the High Plains.” In Archaeological Landscapes on the High Plains, edited by Laura Scheiber and Bonnie Clark, 203–36. Boulder: University Press of Colorado. Domínguez-Rodrigo, Manuel, Sixto Fernández-López, and Luis Alcalá. 2011. “How Can Taphonomy be Defined in the XXI Century?” Journal of Taphonomy 9: 1–13. Efremov, Ivan A. 1940. “Taphonomy: A New Branch of Paleontology.” Pan American Geologist 74: 81–93. Gifford, Diane. 1981. “Taphonomy and Paleoecology: A Critical Review of Archeology’s Sister Discipline.” Advances in Archaeological Method and Theory 4: 365–438. DOI:10.1016/b978-0-12-0031047.50013-2. Hiscock, Peter. 1985. “The Need for a Taphonomic Perspective in Stone Artefact Analysis.” Queensland Archaeological Research 2: 82–95. Lyman, Robert Lee. 1994. Vertebrate Taphonomy. Cambridge: Cambridge University Press. Weigelt, Johannes. [1927] 1989. Recent Vertebrate Carcasses and their Paleobiological Implications. Chicago: University of Chicago Press. REFERENCES FURTHER READINGS Behrensmeyer, Anne K., and Susan M. Kidwell. 1985. “Taphonomy’s Contribution to Paleobiology.” Paleobiology 11: 105–9. DOI:10.1017/s00948373000 1143x. Andrews, Peter. 1990. Owls, Cave and Fossils. Chicago: University of Chicago Press. Haglund, William D., and Marcella Sorg, eds. 1997. Forensic Taphonomy. New York: CRC Press. • • Taphonomy has become a powerful and necessary tool for disciplines dealing with the fossil record. Current research suggests that the incorporation of a taphonomic perspective improves the understanding of the sources of variation for every component of archaeological assemblages. Finally yet importantly, a widespread integration of taphonomy in cultural and natural resource management is highly beneficial for improving conservation policies and sustainable practices worldwide.