• 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.

      • microbial, biogeochemical, and larger-scale controls on the preservation of different tissue types; in particular, exceptional preservation in Konzervat-lagerstätten. Covered within this field is the dominance of biological versus physical agents in the destruction of remains from all major taxonomic groups (plants, invertebrates, vertebrates).
      • processes that concentrate biological remains; especially the degree to which different types of assemblages reflect the species composition and abundance of source faunas and floras.
      • the spatio-temporal resolution and ecological fidelity of species assemblages, particularly the relatively minor role of out-of-habitat transport contrasted with the major effects of time-averaging.
      • the outlines of megabiases in the fossil record, including the evolution of new bauplans and behavioral capabilities, and by broad-scale changes in climate, tectonics, and geochemistry of Earth surface systems.
      • The Mars Science Laboratory mission objectives evolved from assessment on ancient Mars habitability to developing predictive models on taphonomy.
      • Search images: field experiments have shown that paleontologists working on, say fossil clams are better at collecting clams than anything else, because their search image has been shaped to bias them in favour of clams.
      • Relative ease of extraction: fossils that are easy to obtain (such as many phosphatic fossils that are easily extracted en masse by dissolution in acid) are overabundant in the fossil record.
      • Taxonomic bias: fossils with easily discernible morphologies will be easy to distinguish as separate species, and will thus have an inflated abundance.
      • Emig, C. C. (2002). "Death: a key information in marine palaeoecology" in Current topics on taphonomy and fossilization, Valencia". Col.lecio Encontres. 5: 21–26. 
      • Greenwood, D. R. (1991), "The taphonomy of plant macrofossils". In, Donovan, S. K. (Ed.), The processes of fossilisation, p. 141-169. Belhaven Press.
      • Lyman, R. L. (1994), Vertebrate Taphonomy. Cambridge University Press.
      • Shipman, P. (1981), Life history of a fossil: An introduction to taphonomy and paleoecology. Harvard University Press.
      • Taylor, P. D.; Wilson, M. A. (2003). "Palaeoecology and evolution of marine hard substrate communities" (PDF). Earth-Science Reviews. 62: 1–103. doi:10.1016/s0012-8252(02)00131-9. 
  • What Else?

    • Taphonomy