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Taphonomy

Taphonomy is the study of how organisms decay and become fossilized or preserved in the paleontological record. The term taphonomy (from Greek táphos, τάφος 'burial' and nomos, νόμος 'law') was introduced to paleontology in 1940[1] by Soviet scientist Ivan Efremov to describe the study of the transition of remains, parts, or products of organisms from the biosphere to the lithosphere.[2][3]

The term taphomorph is used to describe fossil structures that represent poorly-preserved, deteriorated remains of a mixture of taxonomic groups, rather than of a single one.

Description Edit

Taphonomic phenomena are grouped into two phases: biostratinomy, events that occur between death of the organism and the burial; and diagenesis, events that occur after the burial.[1] Since Efremov's definition, taphonomy has expanded to include the fossilization of organic and inorganic materials through both cultural and environmental influences. Taphonomy is now most widely defined as the study of what happens to objects after they leave the biosphere (living contexts), enter the lithosphere (buried contexts), and are subsequently recovered and studied.[4]

This is a multidisciplinary concept and is used in slightly different contexts throughout different fields of study. Fields that employ the concept of taphonomy include:

 
An articulated wombat skeleton in Imperial-Diamond cave (Jenolan Caves)
 
The La Brea Tar Pits represent an unusual depositional environment for their epoch (Pleistocene) and location (southern California).

There are five main stages of taphonomy: disarticulation, dispersal, accumulation, fossilization, and mechanical alteration.[5] The first stage, disarticulation, occurs as the organism decays and the bones are no longer held together by the flesh and tendons of the organism. Dispersal is the separation of pieces of an organism caused by natural events (i.e. floods, scavengers etc.). Accumulation occurs when there is a buildup of organic and/or inorganic materials in one location (scavengers or human behavior). When mineral rich groundwater permeates organic materials and fills the empty spaces, a fossil is formed. The final stage of taphonomy is mechanical alteration; these are the processes that physically alter the remains (i.e. freeze-thaw, compaction, transport, burial).[6] It should be added that these "stages" are not only successive, they interplay. For example, chemical changes occur at every stage of the process, because of bacteria. "Changes" begin as soon as the death of the organism: enzymes are released that destroy the organic contents of the tissues, and mineralised tissues such as bone, enamel and dentin are a mixture of organic and mineral components. Moreover, most often the organisms (vegetal or animal) are dead because they have been "killed" by a predator. The digestion modifies the composition of the flesh, but also that of the bones.[7][8]

Research areas Edit

 
Actualistic taphonomy seeks to understand taphonomic processes through experimentation, such as the burial of bone.[9]

Taphonomy has undergone an explosion of interest since the 1980s,[10] with research focusing on certain areas.

  • 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.
  • Actualistic taphonomy uses the present to understand past taphonomic events. This is often done through controlled experiments,[11] such as the role microbes play in fossilization,[12] the effects of mammalian carnivores on bone,[13] or the burial of bone in a water flume.[9] Computer modeling is also used to explain taphonomic events.[9][14]
  • The spatio-temporal resolution[clarification needed] and ecological fidelity[clarification needed] of species assemblages, particularly the relatively minor role of out-of-habitat transport contrasted with the major effects of time-averaging.[clarification needed]
  • 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 of ancient Mars habitability to developing predictive models on taphonomy.[clarification needed][15]

Paleontology Edit

One motivation behind taphonomy is to understand biases present in the fossil record better. 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.

Forensic science Edit

Forensic taphonomy is a relatively new field that has increased in popularity in the past 15 years. It is a subfield of forensic anthropology focusing specifically on how taphonomic forces have altered criminal evidence.[16]

There are two different branches of forensic taphonomy: biotaphonomy and geotaphonomy. Biotaphonomy looks at how the decomposition and/or destruction of the organism has happened. The main factors that affect this branch are categorized into three groups: environmental factors; external variables, individual factors; factors from the organism itself (i.e. body size, age, etc.), and cultural factors; factors specific to any cultural behaviors that would affect the decomposition (burial practices). Geotaphonomy studies how the burial practices and the burial itself affects the surrounding environment. This includes soil disturbances and tool marks from digging the grave, disruption of plant growth and soil pH from the decomposing body, and the alteration of the land and water drainage from introducing an unnatural mass to the area.[17]

This field is extremely important because it helps scientists use the taphonomic profile to help determine what happened to the remains at the time of death (perimortem) and after death (postmortem). This can make a huge difference when considering what can be used as evidence in a criminal investigation.[18]

Archaeology Edit

Taphonomy is an important study for Archaeologists to better interpret archaeological sites. Since the archaeological record is often incomplete, taphonomy helps explain how it became incomplete. The methodology of taphonomy involves observing transformation processes in order to understand their impact on archaeological material and interpret patterns on real sites.[19] This is mostly in the form of assessing how the deposition of the preserved remains of an organism (usually animal bones) has occurred to better understand a deposit.

Whether the deposition was a result of human, animals and/or the environment is often the goal of taphonomic study. Archaeologists typically separate natural from cultural processes when identifying evidence of human interaction with faunal remains.[20] This is done by looking at human processes preceding artifact discard in addition to processes after artifact discard. Changes preceding discard include butchering, skinning, and cooking. Understanding these processes can inform archaeologists on tool use or how an animal was processed.[21] When the artifact is deposited, abiotic and biotic modifications occur. These can include thermal alteration, rodent disturbances, gnaw marks, and the effects of soil pH to name a few.

While taphonomic methodology can be applied and used to study a variety of materials such as buried ceramics and lithics, its primary application in archaeology involves the examination of organic residues.[4] Interpretation of the post-mortem, pre-, and post-burial histories of faunal assemblages is critical in determining their association with hominid activity and behaviour.[22]

For instance, to distinguish the bone assemblages that are produced by humans from those of non humans, much ethnoarchaeological observation has been done on different human groups and carnivores, to ascertain if there is anything different in the accumulation and fragmentation of bones. This study has also come in the form of excavation of animal dens and burrows to study the discarded bones and experimental breakage of bones with and without stone tools.[23]

 
Taphonomic study of the Taung child skull claims they were likely killed by a large bird, indicated by traces of talon cuts.[24]

Studies of this kind by C.K. Brain in South Africa have shown that bone fractures previously attributed to “killer man-apes” were in fact caused by the pressure of overlying rocks and earth in limestone caves.[23] His research has also demonstrated that early hominins, for example australopithecines, were more likely preyed upon by carnivores rather than being hunters themselves, from cave sites such as Swartkrans in South Africa.[23]

Outside of Africa Lewis Binford observed the effects of wolves and dogs on bones in Alaska and the American Southwest, differentiating the interference of humans and carnivores on bone remains by the number of bone splinters and the number of intact articular ends. He observed that animals gnaw and attack the articular ends first leaving mostly bone cylinders behind, therefore it can be assumed a deposit with a high number of bone cylinders and a low number of bones with articular ends intact is therefore probably the result of carnivore activity.[23] In practice John Speth applied this criteria to the bones from the Garnsey site in New Mexico. The rarity of bone cylinders indicated that there had been minimal destruction by scavengers, and that the bone assemblage could be assumed to be wholly the result of human activity, butchering the animals for meat and marrow extraction.[25]

One of the most important elements in this methodology is replication, to confirm the validity of results.[19]

There are limitations to this kind of taphonomic study in archaeological deposits as any analysis has to presume that processes in the past were the same as today, e.g that living carnivores behaved in a similar way to those in prehistoric times. There are wide variations among existing species so determining the behavioural patterns of extinct species is sometimes hard to justify. Moreover, the differences between faunal assemblages of animals and humans is not always so distinct, hyenas and humans display similar patterning in breakage and form similarly shaped fragments as the ways in which a bone can break are limited.[23] Since large bones survive better than plants this also has created a bias and inclination towards big-game hunting rather than gathering when considering prehistoric economies.[19]

While all of archaeology studies taphonomy to some extend, certain subfields deal with it more than others. These include zooarchaeology, geoarchaeology, and paleoethnobotany.

Microbial Mats Edit

Modern experiments have been conducted on post-mortem invertebrates and vertebrates to understand how microbial mats and microbial activity influence the formation of fossils and the preservation of soft tissues.[26][27] In these studies, microbial mats entomb animal carcasses in a sarcophagus of microbes—the sarcophagus entombing the animal's carcass delays decay.[26] Entombed carcasses were observed to be more intact than non-entombed counter-parts by years at a time. Microbial mats maintained and stabilized the articulation of the joints and the skeleton of post-mortem organisms, as seen in frog carcasses for up to 1080 days after coverage by the mats.[26] The environment within the entombed carcasses is typically described as anoxic and acidic during the initial stage of decomposition.[26][28] These conditions are perpetuated by the exhaustion of oxygen by aerobic bacteria within the carcass creating an environment ideal for the preservation of soft tissues, such as muscle tissue and brain tissue.[26][27] The anoxic and acidic conditions created by that mats also inhibit the process of autolysis within the carcasses delaying decay even further.[29]  Endogenous gut bacteria have also been described to aid the preservation of invertebrate soft tissue by delaying decay and stabilizing soft tissue structures.[29] Gut bacteria form pseudomorphs replicating the form of soft tissues within the animal. These pseudomorphs are possible explanation for the increased occurrence of preserved guts impression among invertebrates.[29] In the later stages of the prolonged decomposition of the carcasses, the environment within the sarcophagus alters to more oxic and basic conditions promoting biomineralization and the precipitation of calcium carbonate.[26][27]

Microbial mats additionally play a role in the formation of molds and impressions of carcasses. These molds and impressions replicate and preserve the integument of animal carcasses.[26] The degree to which has been demonstrated in frog skin preservation. The original morphology of the frog skin, including structures such as warts, was preserved for more than 1.5 years. The microbial mats also aided in the formation of the mineral gypsum embedded within the frog skin.[26] The microbes that constitute the microbial mats in addition to forming a sarcophagus, secrete an exopolymeric substances (EPS) that drive biomineralization. The EPS provides a nucleated center for biomineralization.[27] During later stages of decomposition heterotrophic microbes degrade the EPS, facilitating the release of calcium ions into the environment and creating a Ca-enriched film. The degradation of the EPS and formation of the Ca-rich film is suggested to aid in the precipitation of calcium carbonate and further the process of biomineralization.[28]

Taphonomic biases in the fossil record Edit

Because of the very select processes that cause preservation, not all organisms have the same chance of being preserved. Any factor that affects the likelihood that an organism is preserved as a fossil is a potential source of bias. It is thus arguably the most important goal of taphonomy to identify the scope of such biases such that they can be quantified to allow correct interpretations of the relative abundances of organisms that make up a fossil biota.[30] Some of the most common sources of bias are listed below.

Physical attributes of the organism itself Edit

This perhaps represents the biggest source of bias in the fossil record. First and foremost, organisms that contain hard parts have a far greater chance of being represented in the fossil record than organisms consisting of soft tissue only. As a result, animals with bones or shells are overrepresented in the fossil record, and many plants are only represented by pollen or spores that have hard walls. Soft-bodied organisms may form 30% to 100% of the biota, but most fossil assemblages preserve none of this unseen diversity, which may exclude groups such as fungi and entire animal phyla from the fossil record. Many animals that moult, on the other hand, are overrepresented, as one animal may leave multiple fossils due to its discarded body parts. Among plants, wind-pollinated species produce so much more pollen than animal-pollinated species, the former being overrepresented relative to the latter.[citation needed]

Characteristics of the habitat Edit

Most fossils form in conditions where material is deposited on the bottom of water bodies. Coastal areas are often prone to high rates of erosion, and rivers flowing into the sea may carry a high particulate load from inland. These sediments will eventually settle out, so organisms living in such environments have a much higher chance of being preserved as fossils after death than do those organisms living in non-depositing conditions. In continental environments, fossilization is likely in lakes and riverbeds that gradually fill in with organic and inorganic material. The organisms of such habitats are also liable to be overrepresented in the fossil record than those living far from these aquatic environments where burial by sediments is unlikely to occur.[31]

Mixing of fossils from different places Edit

A sedimentary deposit may have experienced a mixing of noncontemporaneous remains within single sedimentary units via physical or biological processes; i.e. a deposit could be ripped up and redeposited elsewhere, meaning that a deposit may contain a large number of fossils from another place (an allochthonous deposit, as opposed to the usual autochthonous). Thus, a question that is often asked of fossil deposits is to what extent does the fossil deposit record the true biota that originally lived there? Many fossils are obviously autochthonous, such as rooted fossils like crinoids,[clarification needed] and many fossils are intrinsically obviously allochthonous, such as the presence of photoautotrophic plankton in a benthic deposit that must have sunk to be deposited. A fossil deposit may thus become biased towards exotic species (i.e. species not endemic to that area) when the sedimentology is dominated by gravity-driven surges, such as mudslides, or may become biased if there are very few endemic organisms to be preserved. This is a particular problem in palynology.[citation needed]

Temporal resolution Edit

Because population turnover rates of individual taxa are much less than net rates of sediment accumulation, the biological remains of successive, noncontemporaneous populations of organisms may be admixed within a single bed, known as time-averaging. Because of the slow and episodic nature of the geologic record, two apparently contemporaneous fossils may have actually lived centuries, or even millennia, apart. Moreover, the degree of time-averaging in an assemblage may vary. The degree varies on many factors, such as tissue type, the habitat, the frequency of burial events and exhumation events, and the depth of bioturbation within the sedimentary column relative to net sediment accumulation rates. Like biases in spatial fidelity, there is a bias towards organisms that can survive reworking events, such as shells. An example of a more ideal deposit with respect to time-averaging bias would be a volcanic ash deposit, which captures an entire biota caught in the wrong place at the wrong time (e.g. the Silurian Herefordshire lagerstätte).

Gaps in time series Edit

The geological record is very discontinuous, and deposition is episodic at all scales. At the largest scale, a sedimentological high-stand period may mean that no deposition may occur for millions of years and, in fact, erosion of the deposit may occur. Such a hiatus is called an unconformity. Conversely, a catastrophic event such as a mudslide may overrepresent a time period. At a shorter scale, scouring processes such as the formation of ripples and dunes and the passing of turbidity currents may cause layers to be removed. Thus the fossil record is biased towards periods of greatest sedimentation; periods of time that have less sedimentation are consequently less well represented in the fossil record.[citation needed]

A related problem is the slow changes that occur in the depositional environment of an area; a deposit may experience periods of poor preservation due to, for example, a lack of biomineralizing elements. This causes the taphonomic or diagenetic obliteration of fossils, producing gaps and condensation of the record.[citation needed]

Consistency in preservation over geologic time Edit

Major shifts in intrinsic and extrinsic properties of organisms, including morphology and behaviour in relation to other organisms or shifts in the global environment, can cause secular or long-term cyclic changes in preservation (megabias).[citation needed]

Human biases Edit

Much of the incompleteness of the fossil record is due to the fact that only a small amount of rock is ever exposed at the surface of the Earth, and not even most of that has been explored. Our fossil record relies on the small amount of exploration that has been done on this. Unfortunately, paleontologists as humans can be very biased in their methods of collection; a bias that must be identified. Potential sources of bias include,

  • 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.[citation needed]

Preservation of biopolymers Edit

 
Although chitin exoskeletons of arthropods such as insects and myriapods (but not trilobites, which are mineralized with calcium carbonate, nor crustaceans, which are often mineralized with calcium phosphate) are subject to decomposition, they often maintain shape during permineralization, especially if they are already somewhat mineralized.
 
Soft-bodied preservation of a lizard, Parachute Creek Member, Green River Formation, Utah. Most of the skeleton decalcified.

The taphonomic pathways involved in relatively inert substances such as calcite (and to a lesser extent bone) are relatively obvious, as such body parts are stable and change little through time. However, the preservation of "soft tissue" is more interesting, as it requires more peculiar conditions. While usually only biomineralised material survives fossilisation, the preservation of soft tissue is not as rare as sometimes thought.[12]

Both DNA and proteins are unstable, and rarely survive more than hundreds of thousands of years before degrading.[32] Polysaccharides also have low preservation potential, unless they are highly cross-linked; this interconnection is most common in structural tissues, and renders them resistant to chemical decay.[33] Such tissues include wood (lignin), spores and pollen (sporopollenin), the cuticles of plants (cutan) and animals, the cell walls of algae (algaenan),[33] and potentially the polysaccharide layer of some lichens.[citation needed] This interconnectedness makes the chemicals less prone to chemical decay, and also means they are a poorer source of energy so less likely to be digested by scavenging organisms.[32] After being subjected to heat and pressure, these cross-linked organic molecules typically "cook" and become kerogen or short (<17 C atoms) aliphatic/aromatic carbon molecules.[32] Other factors affect the likelihood of preservation; for instance sclerotization renders the jaws of polychaetes more readily preserved than the chemically equivalent but non-sclerotized body cuticle.[33] A peer-reviewed study in 2023 was the first to present an in-depth chemical description of how biological tissues and cells potentially preserve into the fossil record. This study generalized the chemistry underlying cell and tissue preservation to explain the phenomenon for potentially any cellular organism.[32]

It was thought that only tough, cuticle type soft tissue could be preserved by Burgess Shale type preservation,[34] but an increasing number of organisms are being discovered that lack such cuticle, such as the probable chordate Pikaia and the shellless Odontogriphus.[35]

It is a common misconception that anaerobic conditions are necessary for the preservation of soft tissue; indeed much decay is mediated by sulfate reducing bacteria which can only survive in anaerobic conditions.[33] Anoxia does, however, reduce the probability that scavengers will disturb the dead organism, and the activity of other organisms is undoubtedly one of the leading causes of soft-tissue destruction.[33]

Plant cuticle is more prone to preservation if it contains cutan, rather than cutin.[33]

Plants and algae produce the most preservable compounds, which are listed according to their preservation potential by Tegellaar (see reference).[36]

Disintegration Edit

How complete fossils are was once thought to be a proxy for the energy of the environment, with stormier waters leaving less articulated carcasses. However, the dominant force actually seems to be predation, with scavengers more likely than rough waters to break up a fresh carcass before it is buried.[37] Sediments cover smaller fossils faster so they are likely to be found fully articulated. However, erosion also tends to destroy smaller fossils more easily.[citation needed]

Distortion Edit

 
Skulls of Diictodon undistorted (top), compressed in a lateral axis (middle) and compressed on a dorsal-ventral axis (bottom)

Often fossils, particularly those of verterbates, are distorted by the subsequent movements of the surrounding sediment, this can include compression of the fossil in a particular axis, as well as shearing.[38]

Significance Edit

Taphonomic processes allow researchers of multiple fields to identify the past of natural and cultural objects. From the time of death or burial until excavation, taphonomy can aid in the understanding of past environments.[13] When studying the past it is important to gain contextual information in order to have a solid understanding of the data. Often these findings can be used to better understand cultural or environmental shifts within the present day.

The term taphomorph is used to collectively describe fossil structures that represent poorly-preserved and deteriorated remains of various taxonomic groups, rather than of a single species. For example, the 579–560 million year old fossil Ediacaran assemblages from Avalonian locations in Newfoundland contain taphomorphs of a mixture of taxa which have collectively been named Ivesheadiomorphs. Originally interpreted as fossils of a single genus, Ivesheadia, they are now thought to be the deteriorated remains of various types of frondose organism. Similarly, Ediacaran fossils from England, once assigned to Blackbrookia, Pseudovendia and Shepshedia, are now all regarded as taphomorphs related to Charnia or Charniodiscus.[39]

Fluvial taphonomy Edit

Fluvial taphonomy is concerned with the decomposition of organisms in rivers. An organism may sink or float within a river, it may also be carried by the current near the surface of the river or near its bottom.[40] Organisms in terrestrial and fluvial environments will not undergo the same processes. A fluvial environment may be colder than a terrestrial environment. The ecosystem of live organisms that scavenge on the organism in question and the abiotic items in rivers will differ than on land. Organisms within a river may also be physically transported by the flow of the river. The flow of the river can additionally erode the surface of the organisms found within it. The processes an organism may undergo in a fluvial environment will result in a slower rate of decomposition within a river compared to on land.[41]

See also Edit

References Edit

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  32. ^ a b c d Anderson, L. A. (May 2023). "A chemical framework for the preservation of fossil vertebrate cells and soft tissues". Earth-Science Reviews. 240: 104367. Bibcode:2023ESRv..24004367A. doi:10.1016/j.earscirev.2023.104367. S2CID 257326012.
  33. ^ a b c d e f Jones, M. K.; Briggs, D. E. G.; Eglington, G.; Hagelberg, E.; Briggs, Derek E. G. (29 January 1999). "Molecular taphonomy of animal and plant cuticles: selective preservation and diagenesis". Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences. 354 (1379): 7–17. doi:10.1098/rstb.1999.0356. PMC 1692454.
  34. ^ Butterfield, Nicholas J. (1990). "Organic preservation of non-mineralizing organisms and the taphonomy of the Burgess Shale". Paleobiology. 16 (3): 272–286. Bibcode:1990Pbio...16..272B. doi:10.1017/S0094837300009994. JSTOR 2400788. S2CID 133486523.
  35. ^ Morris, Simon Conway (March 2008). "A redescription of a rare chordate, Metaspriggina Walcotti Simonetta and Insom, from the Burgess Shale (Middle Cambrian), British Columbia, Canada". Journal of Paleontology. 82 (2): 424–430. Bibcode:2008JPal...82..424M. doi:10.1666/06-130.1. S2CID 85619898.
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  37. ^ Behrensmeyer, Anna K.; Kidwell, Susan M.; Gastaldo, Robert A. (December 2000). "Taphonomy and paleobiology". Paleobiology. 26: 103–147. doi:10.1666/0094-8373(2000)26[103:TAP]2.0.CO;2. S2CID 39048746.
  38. ^ Kammerer, Christian F.; Deutsch, Michol; Lungmus, Jacqueline K.; Angielczyk, Kenneth D. (2020-10-07). "Effects of taphonomic deformation on geometric morphometric analysis of fossils: a study using the dicynodont Diictodon feliceps (Therapsida, Anomodontia)". PeerJ. 8: e9925. doi:10.7717/peerj.9925. ISSN 2167-8359. PMC 7547620. PMID 33083110.
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  40. ^ Sorg, Marcella; Haglund, William (2001-07-30), "Advancing Forensic Taphonomy: Purpose, Theory, and Process", Advances in Forensic Taphonomy, CRC Press, pp. 3–29, doi:10.1201/9781420058352-3, ISBN 978-0-8493-1189-5, retrieved 2022-04-11
  41. ^ Pokines, James T.; Symes, Steve A.; L'Abbé, Ericka N., eds. (December 2021). Manual of forensic taphonomy. CRC Press. pp. 115–134. ISBN 978-0-367-77437-0. OCLC 1256590576.

Further reading Edit

  • Emig, C. C. (2002). "Death: a key information in marine palaeoecology". Current topics on taphonomy and fossilization. Col.lecio Encontres. Vol. 5. Valencia. pp. 21–26. ISBN 9788484840367. OCLC 49214974.{{cite book}}: CS1 maint: location missing publisher (link)
  • Greenwood, D. R. (1991). "The taphonomy of plant macrofossils". In Donovan, S. K. (ed.). The processes of fossilisation. Belhaven Press. pp. 141–169.
  • Lyman, R. L. (1994). Vertebrate Taphonomy. Cambridge University Press. doi:10.1017/CBO9781139878302. ISBN 9780521452151.
  • Shipman, P. (1981). Life history of a fossil: An introduction to taphonomy and paleoecology. Harvard University Press. ISBN 0674530853.
  • Taylor, P.D.; Wilson, M.A. (July 2003). "Palaeoecology and evolution of marine hard substrate communities" (PDF). Earth-Science Reviews. 62 (1–2): 1–103. Bibcode:2003ESRv...62....1T. doi:10.1016/S0012-8252(02)00131-9.

External links Edit

  • The is the first long-term large-scale deployment and re-collection of organism remains on the sea floor.
  • Journal of Taphonomy
  • at the College of Wooster
  • compiled by Mark A. Wilson
  • Taphonomy
  • Minerals and the Origins of Life (Robert Hazen, NASA) (video, 60m, April 2014).
  • 7th International Meeting on Taphonomy and Fossilization (Taphos 2014), at the Università degli studi di Ferrara, Italy, 10–13 September 2014

taphonomy, study, organisms, decay, become, fossilized, preserved, paleontological, record, term, taphonomy, from, greek, táphos, τάφος, burial, nomos, νόμος, introduced, paleontology, 1940, soviet, scientist, ivan, efremov, describe, study, transition, remain. Taphonomy is the study of how organisms decay and become fossilized or preserved in the paleontological record The term taphonomy from Greek taphos tafos burial and nomos nomos law was introduced to paleontology in 1940 1 by Soviet scientist Ivan Efremov to describe the study of the transition of remains parts or products of organisms from the biosphere to the lithosphere 2 3 The term taphomorph is used to describe fossil structures that represent poorly preserved deteriorated remains of a mixture of taxonomic groups rather than of a single one Contents 1 Description 2 Research areas 2 1 Paleontology 2 2 Forensic science 2 3 Archaeology 2 4 Microbial Mats 3 Taphonomic biases in the fossil record 3 1 Physical attributes of the organism itself 3 2 Characteristics of the habitat 3 3 Mixing of fossils from different places 3 4 Temporal resolution 3 5 Gaps in time series 3 6 Consistency in preservation over geologic time 3 7 Human biases 4 Preservation of biopolymers 5 Disintegration 6 Distortion 7 Significance 8 Fluvial taphonomy 9 See also 10 References 11 Further reading 12 External linksDescription EditTaphonomic phenomena are grouped into two phases biostratinomy events that occur between death of the organism and the burial and diagenesis events that occur after the burial 1 Since Efremov s definition taphonomy has expanded to include the fossilization of organic and inorganic materials through both cultural and environmental influences Taphonomy is now most widely defined as the study of what happens to objects after they leave the biosphere living contexts enter the lithosphere buried contexts and are subsequently recovered and studied 4 This is a multidisciplinary concept and is used in slightly different contexts throughout different fields of study Fields that employ the concept of taphonomy include Archaeobotany Archaeology Biology Forensic science Geoarchaeology Geology Paleoecology Paleontology Zooarchaeology nbsp An articulated wombat skeleton in Imperial Diamond cave Jenolan Caves nbsp The La Brea Tar Pits represent an unusual depositional environment for their epoch Pleistocene and location southern California There are five main stages of taphonomy disarticulation dispersal accumulation fossilization and mechanical alteration 5 The first stage disarticulation occurs as the organism decays and the bones are no longer held together by the flesh and tendons of the organism Dispersal is the separation of pieces of an organism caused by natural events i e floods scavengers etc Accumulation occurs when there is a buildup of organic and or inorganic materials in one location scavengers or human behavior When mineral rich groundwater permeates organic materials and fills the empty spaces a fossil is formed The final stage of taphonomy is mechanical alteration these are the processes that physically alter the remains i e freeze thaw compaction transport burial 6 It should be added that these stages are not only successive they interplay For example chemical changes occur at every stage of the process because of bacteria Changes begin as soon as the death of the organism enzymes are released that destroy the organic contents of the tissues and mineralised tissues such as bone enamel and dentin are a mixture of organic and mineral components Moreover most often the organisms vegetal or animal are dead because they have been killed by a predator The digestion modifies the composition of the flesh but also that of the bones 7 8 Research areas Edit nbsp Actualistic taphonomy seeks to understand taphonomic processes through experimentation such as the burial of bone 9 Taphonomy has undergone an explosion of interest since the 1980s 10 with research focusing on certain areas Microbial biogeochemical and larger scale controls on the preservation of different tissue types in particular exceptional preservation in Konzervat lagerstatten 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 Actualistic taphonomy uses the present to understand past taphonomic events This is often done through controlled experiments 11 such as the role microbes play in fossilization 12 the effects of mammalian carnivores on bone 13 or the burial of bone in a water flume 9 Computer modeling is also used to explain taphonomic events 9 14 The spatio temporal resolution clarification needed and ecological fidelity clarification needed of species assemblages particularly the relatively minor role of out of habitat transport contrasted with the major effects of time averaging clarification needed 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 of ancient Mars habitability to developing predictive models on taphonomy clarification needed 15 Paleontology Edit One motivation behind taphonomy is to understand biases present in the fossil record better 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 Forensic science Edit Forensic taphonomy is a relatively new field that has increased in popularity in the past 15 years It is a subfield of forensic anthropology focusing specifically on how taphonomic forces have altered criminal evidence 16 There are two different branches of forensic taphonomy biotaphonomy and geotaphonomy Biotaphonomy looks at how the decomposition and or destruction of the organism has happened The main factors that affect this branch are categorized into three groups environmental factors external variables individual factors factors from the organism itself i e body size age etc and cultural factors factors specific to any cultural behaviors that would affect the decomposition burial practices Geotaphonomy studies how the burial practices and the burial itself affects the surrounding environment This includes soil disturbances and tool marks from digging the grave disruption of plant growth and soil pH from the decomposing body and the alteration of the land and water drainage from introducing an unnatural mass to the area 17 This field is extremely important because it helps scientists use the taphonomic profile to help determine what happened to the remains at the time of death perimortem and after death postmortem This can make a huge difference when considering what can be used as evidence in a criminal investigation 18 Archaeology Edit Taphonomy is an important study for Archaeologists to better interpret archaeological sites Since the archaeological record is often incomplete taphonomy helps explain how it became incomplete The methodology of taphonomy involves observing transformation processes in order to understand their impact on archaeological material and interpret patterns on real sites 19 This is mostly in the form of assessing how the deposition of the preserved remains of an organism usually animal bones has occurred to better understand a deposit Whether the deposition was a result of human animals and or the environment is often the goal of taphonomic study Archaeologists typically separate natural from cultural processes when identifying evidence of human interaction with faunal remains 20 This is done by looking at human processes preceding artifact discard in addition to processes after artifact discard Changes preceding discard include butchering skinning and cooking Understanding these processes can inform archaeologists on tool use or how an animal was processed 21 When the artifact is deposited abiotic and biotic modifications occur These can include thermal alteration rodent disturbances gnaw marks and the effects of soil pH to name a few While taphonomic methodology can be applied and used to study a variety of materials such as buried ceramics and lithics its primary application in archaeology involves the examination of organic residues 4 Interpretation of the post mortem pre and post burial histories of faunal assemblages is critical in determining their association with hominid activity and behaviour 22 For instance to distinguish the bone assemblages that are produced by humans from those of non humans much ethnoarchaeological observation has been done on different human groups and carnivores to ascertain if there is anything different in the accumulation and fragmentation of bones This study has also come in the form of excavation of animal dens and burrows to study the discarded bones and experimental breakage of bones with and without stone tools 23 nbsp Taphonomic study of the Taung child skull claims they were likely killed by a large bird indicated by traces of talon cuts 24 Studies of this kind by C K Brain in South Africa have shown that bone fractures previously attributed to killer man apes were in fact caused by the pressure of overlying rocks and earth in limestone caves 23 His research has also demonstrated that early hominins for example australopithecines were more likely preyed upon by carnivores rather than being hunters themselves from cave sites such as Swartkrans in South Africa 23 Outside of Africa Lewis Binford observed the effects of wolves and dogs on bones in Alaska and the American Southwest differentiating the interference of humans and carnivores on bone remains by the number of bone splinters and the number of intact articular ends He observed that animals gnaw and attack the articular ends first leaving mostly bone cylinders behind therefore it can be assumed a deposit with a high number of bone cylinders and a low number of bones with articular ends intact is therefore probably the result of carnivore activity 23 In practice John Speth applied this criteria to the bones from the Garnsey site in New Mexico The rarity of bone cylinders indicated that there had been minimal destruction by scavengers and that the bone assemblage could be assumed to be wholly the result of human activity butchering the animals for meat and marrow extraction 25 One of the most important elements in this methodology is replication to confirm the validity of results 19 There are limitations to this kind of taphonomic study in archaeological deposits as any analysis has to presume that processes in the past were the same as today e g that living carnivores behaved in a similar way to those in prehistoric times There are wide variations among existing species so determining the behavioural patterns of extinct species is sometimes hard to justify Moreover the differences between faunal assemblages of animals and humans is not always so distinct hyenas and humans display similar patterning in breakage and form similarly shaped fragments as the ways in which a bone can break are limited 23 Since large bones survive better than plants this also has created a bias and inclination towards big game hunting rather than gathering when considering prehistoric economies 19 While all of archaeology studies taphonomy to some extend certain subfields deal with it more than others These include zooarchaeology geoarchaeology and paleoethnobotany Microbial Mats Edit Modern experiments have been conducted on post mortem invertebrates and vertebrates to understand how microbial mats and microbial activity influence the formation of fossils and the preservation of soft tissues 26 27 In these studies microbial mats entomb animal carcasses in a sarcophagus of microbes the sarcophagus entombing the animal s carcass delays decay 26 Entombed carcasses were observed to be more intact than non entombed counter parts by years at a time Microbial mats maintained and stabilized the articulation of the joints and the skeleton of post mortem organisms as seen in frog carcasses for up to 1080 days after coverage by the mats 26 The environment within the entombed carcasses is typically described as anoxic and acidic during the initial stage of decomposition 26 28 These conditions are perpetuated by the exhaustion of oxygen by aerobic bacteria within the carcass creating an environment ideal for the preservation of soft tissues such as muscle tissue and brain tissue 26 27 The anoxic and acidic conditions created by that mats also inhibit the process of autolysis within the carcasses delaying decay even further 29 Endogenous gut bacteria have also been described to aid the preservation of invertebrate soft tissue by delaying decay and stabilizing soft tissue structures 29 Gut bacteria form pseudomorphs replicating the form of soft tissues within the animal These pseudomorphs are possible explanation for the increased occurrence of preserved guts impression among invertebrates 29 In the later stages of the prolonged decomposition of the carcasses the environment within the sarcophagus alters to more oxic and basic conditions promoting biomineralization and the precipitation of calcium carbonate 26 27 Microbial mats additionally play a role in the formation of molds and impressions of carcasses These molds and impressions replicate and preserve the integument of animal carcasses 26 The degree to which has been demonstrated in frog skin preservation The original morphology of the frog skin including structures such as warts was preserved for more than 1 5 years The microbial mats also aided in the formation of the mineral gypsum embedded within the frog skin 26 The microbes that constitute the microbial mats in addition to forming a sarcophagus secrete an exopolymeric substances EPS that drive biomineralization The EPS provides a nucleated center for biomineralization 27 During later stages of decomposition heterotrophic microbes degrade the EPS facilitating the release of calcium ions into the environment and creating a Ca enriched film The degradation of the EPS and formation of the Ca rich film is suggested to aid in the precipitation of calcium carbonate and further the process of biomineralization 28 Taphonomic biases in the fossil record EditThis section needs additional citations for verification Please help improve this article by adding citations to reliable sources in this section Unsourced material may be challenged and removed April 2011 Learn how and when to remove this template message Because of the very select processes that cause preservation not all organisms have the same chance of being preserved Any factor that affects the likelihood that an organism is preserved as a fossil is a potential source of bias It is thus arguably the most important goal of taphonomy to identify the scope of such biases such that they can be quantified to allow correct interpretations of the relative abundances of organisms that make up a fossil biota 30 Some of the most common sources of bias are listed below Physical attributes of the organism itself Edit This perhaps represents the biggest source of bias in the fossil record First and foremost organisms that contain hard parts have a far greater chance of being represented in the fossil record than organisms consisting of soft tissue only As a result animals with bones or shells are overrepresented in the fossil record and many plants are only represented by pollen or spores that have hard walls Soft bodied organisms may form 30 to 100 of the biota but most fossil assemblages preserve none of this unseen diversity which may exclude groups such as fungi and entire animal phyla from the fossil record Many animals that moult on the other hand are overrepresented as one animal may leave multiple fossils due to its discarded body parts Among plants wind pollinated species produce so much more pollen than animal pollinated species the former being overrepresented relative to the latter citation needed Characteristics of the habitat Edit Most fossils form in conditions where material is deposited on the bottom of water bodies Coastal areas are often prone to high rates of erosion and rivers flowing into the sea may carry a high particulate load from inland These sediments will eventually settle out so organisms living in such environments have a much higher chance of being preserved as fossils after death than do those organisms living in non depositing conditions In continental environments fossilization is likely in lakes and riverbeds that gradually fill in with organic and inorganic material The organisms of such habitats are also liable to be overrepresented in the fossil record than those living far from these aquatic environments where burial by sediments is unlikely to occur 31 Mixing of fossils from different places Edit A sedimentary deposit may have experienced a mixing of noncontemporaneous remains within single sedimentary units via physical or biological processes i e a deposit could be ripped up and redeposited elsewhere meaning that a deposit may contain a large number of fossils from another place an allochthonous deposit as opposed to the usual autochthonous Thus a question that is often asked of fossil deposits is to what extent does the fossil deposit record the true biota that originally lived there Many fossils are obviously autochthonous such as rooted fossils like crinoids clarification needed and many fossils are intrinsically obviously allochthonous such as the presence of photoautotrophic plankton in a benthic deposit that must have sunk to be deposited A fossil deposit may thus become biased towards exotic species i e species not endemic to that area when the sedimentology is dominated by gravity driven surges such as mudslides or may become biased if there are very few endemic organisms to be preserved This is a particular problem in palynology citation needed Temporal resolution Edit Because population turnover rates of individual taxa are much less than net rates of sediment accumulation the biological remains of successive noncontemporaneous populations of organisms may be admixed within a single bed known as time averaging Because of the slow and episodic nature of the geologic record two apparently contemporaneous fossils may have actually lived centuries or even millennia apart Moreover the degree of time averaging in an assemblage may vary The degree varies on many factors such as tissue type the habitat the frequency of burial events and exhumation events and the depth of bioturbation within the sedimentary column relative to net sediment accumulation rates Like biases in spatial fidelity there is a bias towards organisms that can survive reworking events such as shells An example of a more ideal deposit with respect to time averaging bias would be a volcanic ash deposit which captures an entire biota caught in the wrong place at the wrong time e g the Silurian Herefordshire lagerstatte Gaps in time series Edit The geological record is very discontinuous and deposition is episodic at all scales At the largest scale a sedimentological high stand period may mean that no deposition may occur for millions of years and in fact erosion of the deposit may occur Such a hiatus is called an unconformity Conversely a catastrophic event such as a mudslide may overrepresent a time period At a shorter scale scouring processes such as the formation of ripples and dunes and the passing of turbidity currents may cause layers to be removed Thus the fossil record is biased towards periods of greatest sedimentation periods of time that have less sedimentation are consequently less well represented in the fossil record citation needed A related problem is the slow changes that occur in the depositional environment of an area a deposit may experience periods of poor preservation due to for example a lack of biomineralizing elements This causes the taphonomic or diagenetic obliteration of fossils producing gaps and condensation of the record citation needed Consistency in preservation over geologic time Edit Major shifts in intrinsic and extrinsic properties of organisms including morphology and behaviour in relation to other organisms or shifts in the global environment can cause secular or long term cyclic changes in preservation megabias citation needed Human biases Edit Much of the incompleteness of the fossil record is due to the fact that only a small amount of rock is ever exposed at the surface of the Earth and not even most of that has been explored Our fossil record relies on the small amount of exploration that has been done on this Unfortunately paleontologists as humans can be very biased in their methods of collection a bias that must be identified Potential sources of bias include 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 citation needed Preservation of biopolymers EditMain article Preservation of biopolymers nbsp Although chitin exoskeletons of arthropods such as insects and myriapods but not trilobites which are mineralized with calcium carbonate nor crustaceans which are often mineralized with calcium phosphate are subject to decomposition they often maintain shape during permineralization especially if they are already somewhat mineralized nbsp Soft bodied preservation of a lizard Parachute Creek Member Green River Formation Utah Most of the skeleton decalcified The taphonomic pathways involved in relatively inert substances such as calcite and to a lesser extent bone are relatively obvious as such body parts are stable and change little through time However the preservation of soft tissue is more interesting as it requires more peculiar conditions While usually only biomineralised material survives fossilisation the preservation of soft tissue is not as rare as sometimes thought 12 Both DNA and proteins are unstable and rarely survive more than hundreds of thousands of years before degrading 32 Polysaccharides also have low preservation potential unless they are highly cross linked this interconnection is most common in structural tissues and renders them resistant to chemical decay 33 Such tissues include wood lignin spores and pollen sporopollenin the cuticles of plants cutan and animals the cell walls of algae algaenan 33 and potentially the polysaccharide layer of some lichens citation needed This interconnectedness makes the chemicals less prone to chemical decay and also means they are a poorer source of energy so less likely to be digested by scavenging organisms 32 After being subjected to heat and pressure these cross linked organic molecules typically cook and become kerogen or short lt 17 C atoms aliphatic aromatic carbon molecules 32 Other factors affect the likelihood of preservation for instance sclerotization renders the jaws of polychaetes more readily preserved than the chemically equivalent but non sclerotized body cuticle 33 A peer reviewed study in 2023 was the first to present an in depth chemical description of how biological tissues and cells potentially preserve into the fossil record This study generalized the chemistry underlying cell and tissue preservation to explain the phenomenon for potentially any cellular organism 32 It was thought that only tough cuticle type soft tissue could be preserved by Burgess Shale type preservation 34 but an increasing number of organisms are being discovered that lack such cuticle such as the probable chordate Pikaia and the shellless Odontogriphus 35 It is a common misconception that anaerobic conditions are necessary for the preservation of soft tissue indeed much decay is mediated by sulfate reducing bacteria which can only survive in anaerobic conditions 33 Anoxia does however reduce the probability that scavengers will disturb the dead organism and the activity of other organisms is undoubtedly one of the leading causes of soft tissue destruction 33 Plant cuticle is more prone to preservation if it contains cutan rather than cutin 33 Plants and algae produce the most preservable compounds which are listed according to their preservation potential by Tegellaar see reference 36 Disintegration EditHow complete fossils are was once thought to be a proxy for the energy of the environment with stormier waters leaving less articulated carcasses However the dominant force actually seems to be predation with scavengers more likely than rough waters to break up a fresh carcass before it is buried 37 Sediments cover smaller fossils faster so they are likely to be found fully articulated However erosion also tends to destroy smaller fossils more easily citation needed Distortion Edit nbsp Skulls of Diictodon undistorted top compressed in a lateral axis middle and compressed on a dorsal ventral axis bottom Often fossils particularly those of verterbates are distorted by the subsequent movements of the surrounding sediment this can include compression of the fossil in a particular axis as well as shearing 38 Significance EditTaphonomic processes allow researchers of multiple fields to identify the past of natural and cultural objects From the time of death or burial until excavation taphonomy can aid in the understanding of past environments 13 When studying the past it is important to gain contextual information in order to have a solid understanding of the data Often these findings can be used to better understand cultural or environmental shifts within the present day The term taphomorph is used to collectively describe fossil structures that represent poorly preserved and deteriorated remains of various taxonomic groups rather than of a single species For example the 579 560 million year old fossil Ediacaran assemblages from Avalonian locations in Newfoundland contain taphomorphs of a mixture of taxa which have collectively been named Ivesheadiomorphs Originally interpreted as fossils of a single genus Ivesheadia they are now thought to be the deteriorated remains of various types of frondose organism Similarly Ediacaran fossils from England once assigned to Blackbrookia Pseudovendia and Shepshedia are now all regarded as taphomorphs related to Charnia or Charniodiscus 39 Fluvial taphonomy EditFluvial taphonomy is concerned with the decomposition of organisms in rivers An organism may sink or float within a river it may also be carried by the current near the surface of the river or near its bottom 40 Organisms in terrestrial and fluvial environments will not undergo the same processes A fluvial environment may be colder than a terrestrial environment The ecosystem of live organisms that scavenge on the organism in question and the abiotic items in rivers will differ than on land Organisms within a river may also be physically transported by the flow of the river The flow of the river can additionally erode the surface of the organisms found within it The processes an organism may undergo in a fluvial environment will result in a slower rate of decomposition within a river compared to on land 41 See also EditBeecher s Trilobite type preservation Bitter Springs type preservation Burgess Shale type preservation Doushantuo type preservation Ediacaran type preservation Fossil record Karen Chin Lagerstatte Permineralization Petrifaction Pseudofossil Trace fossilReferences Edit a b Lyman R Lee 2010 01 01 What Taphonomy Is What it Isn t and Why Taphonomists Should Care about the Difference PDF Journal of Taphonomy 8 1 1 16 Archived from the original PDF on 2021 07 02 Retrieved 2021 04 20 Efremov I A 1940 Taphonomy a new branch of paleontology Pan American Geology 74 81 93 Archived from the original on 2008 04 03 Martin Ronald E 1999 1 1 The foundations of taphonomy Taphonomy A Process Approach Cambridge University Press Cambridge England p 1 ISBN 0 521 59833 8 a b Stahl Peter W 2014 Vertebrate Taphonomy in Archaeological Research in Smith Claire ed Encyclopedia of Global Archaeology New York NY Springer New York pp 7617 7623 doi 10 1007 978 1 4419 0465 2 2134 ISBN 978 1 4419 0426 3 retrieved 2023 05 12 TAPHONOMY personal colby edu Retrieved 2017 05 03 Taphonomy amp Preservation paleo cortland edu Archived from the original on 2017 05 17 Retrieved 2017 05 03 Brugal J P Coordinateur 2017 07 01 TaphonomieS GDR 3591 CNRS INEE Paris Archives contemporaines ISBN 978 2813002419 OCLC 1012395802 Dauphin Y 2014 in Manuel de taphonomie Denys C Patou Mathis M coordinatrices Arles Errance ISBN 9782877725774 OCLC 892625160 a b c Carpenter Kenneth 30 April 2020 Hydraulic modeling and computational fluid dynamics of bone burial in a sandy river channel Geology of the Intermountain West 7 97 120 doi 10 31711 giw v7 pp97 120 Behrensmeyer A K S M Kidwell R A Gastaldo 2009 Taphonomy and paleobiology Andrews P 1995 Experiments in taphonomy Journal of Archaeological Science 22 2 147 153 Bibcode 1995JArSc 22 147A doi 10 1006 jasc 1995 0016 via Elsevier Science Direct a b Briggs Derek E G Kear Amanda J 1993 Decay and preservation of polychaetes taphonomic thresholds in soft bodied organisms Paleobiology 19 1 107 135 Bibcode 1993Pbio 19 107B doi 10 1017 S0094837300012343 S2CID 84073818 a b Lyman R Lee Vertebrate taphonomy Cambridge Cambridge University Press 1994 page needed Olszewski Thomas D 2004 Modeling the Influence of Taphonomic Destruction Reworking and Burial on Time Averaging in Fossil Accumulations PALAIOS 19 1 39 50 Bibcode 2004Palai 19 39O doi 10 1669 0883 1351 2004 019 lt 0039 MTIOTD gt 2 0 CO 2 S2CID 130117819 Grotzinger John P 24 January 2014 Habitability Taphonomy and the Search for Organic Carbon on Mars Science 343 6169 386 387 Bibcode 2014Sci 343 386G doi 10 1126 science 1249944 PMID 24458635 Passalacqua Nicholas Introduction to Part VI Forensic taphonomy a href Template Cite journal html title Template Cite journal cite journal a Cite journal requires journal help Forensic taphonomy Crime Scene Investigator CSI and forensics information 2011 12 08 verification needed Front Matter Manual of Forensic Taphonomy 2013 pp i xiv doi 10 1201 b15424 1 ISBN 978 1 4398 7841 5 a b c Grant Jim Gorin Sam Fleming Neil 2015 03 27 The Archaeology Coursebook 0 ed Routledge doi 10 4324 9781315727837 ISBN 978 1 317 54111 0 Lyman R Lee 1994 07 07 Vertebrate Taphonomy 1 ed Cambridge University Press doi 10 1017 cbo9781139878302 ISBN 978 0 521 45215 1 Rainsford Clare O Connor Terry June 2016 Taphonomy and contextual zooarchaeology in urban deposits at York UK Archaeological and Anthropological Sciences 8 2 343 351 doi 10 1007 s12520 015 0268 x ISSN 1866 9557 S2CID 127652031 Forbes Shari 2014 Taphonomy in Bioarchaeology and Human Osteology in Smith Claire ed Encyclopedia of Global Archaeology New York NY Springer New York pp 7219 7225 doi 10 1007 978 1 4419 0465 2 137 ISBN 978 1 4419 0426 3 retrieved 2023 05 12 a b c d e Renfrew Colin Bahn Paul 2020 Archaeology Theory Methods and Practice 8th ed London Thames amp Hudson pp 89 90 ISBN 9780500843208 Berger Lee R October 2006 Brief communication Predatory bird damage to the Taung type skull ofAustralopithecus africanus Dart 1925 American Journal of Physical Anthropology 131 2 166 168 doi 10 1002 ajpa 20415 ISSN 0002 9483 PMID 16739138 Speth John D Parry William J 1978 Late Prehistoric Bison Procurement in Southeastern New Mexico The 1977 Season at the Garnsey Site Ann Arbor MI U OF M MUSEUM ANTHRO ARCHAEOLOGY doi 10 3998 mpub 11395480 ISBN 978 0 932206 73 2 a b c d e f g h Iniesto M Villalba I Buscalioni A D Guerrero M C Lopez Archilla A I May 2017 The Effect Of microbial Mats In The Decay Of Anurans With Implications For Understanding Taphonomic Processes In The Fossil Record Scientific Reports 7 1 45160 Bibcode 2017NatSR 745160I doi 10 1038 srep45160 ISSN 2045 2322 PMC 5364532 PMID 28338095 a b c d Iniesto Miguel Buscalioni Angela D Carmen Guerrero M Benzerara Karim Moreira David Lopez Archilla Ana I 2016 05 10 Involvement of microbial mats in early fossilization by decay delay and formation of impressions and replicas of vertebrates and invertebrates Scientific Reports 6 1 25716 Bibcode 2016NatSR 625716I doi 10 1038 srep25716 ISSN 2045 2322 PMC 4861970 PMID 27162204 a b INIESTO MIGUEL LAGUNA CELIA FLORIN MAXIMO GUERRERO M CARMEN CHICOTE ALVARO BUSCALIONI ANGELA D LoPEZ ARCHILLA ANA I 2015 The Impact of Microbial Mats and Their Microenvironmental Conditions in Early Decay of Fish PALAIOS 30 11 12 792 801 Bibcode 2015Palai 30 792I doi 10 2110 palo 2014 086 ISSN 0883 1351 JSTOR 44708731 S2CID 73644674 a b c Butler Aodhan D Cunningham John A Budd Graham E Donoghue Philip C J 2015 06 07 Experimental taphonomy of Artemia reveals the role of endogenous microbes in mediating decay and fossilization Proceedings of the Royal Society B Biological Sciences 282 1808 20150476 doi 10 1098 rspb 2015 0476 PMC 4455810 PMID 25972468 Kidwell Susan M Brenchley Patrick J 1996 Evolution of the fossil record thickness trends in marine skeletal accumulations and their implication Evolutionary Paleobiology In Honor of James W Valentine University of Chicago Press pp 290 336 ISBN 9780226389110 How are dinosaur fossils formed www nhm ac uk Retrieved 19 February 2022 a b c d Anderson L A May 2023 A chemical framework for the preservation of fossil vertebrate cells and soft tissues Earth Science Reviews 240 104367 Bibcode 2023ESRv 24004367A doi 10 1016 j earscirev 2023 104367 S2CID 257326012 a b c d e f Jones M K Briggs D E G Eglington G Hagelberg E Briggs Derek E G 29 January 1999 Molecular taphonomy of animal and plant cuticles selective preservation and diagenesis Philosophical Transactions of the Royal Society of London Series B Biological Sciences 354 1379 7 17 doi 10 1098 rstb 1999 0356 PMC 1692454 Butterfield Nicholas J 1990 Organic preservation of non mineralizing organisms and the taphonomy of the Burgess Shale Paleobiology 16 3 272 286 Bibcode 1990Pbio 16 272B doi 10 1017 S0094837300009994 JSTOR 2400788 S2CID 133486523 Morris Simon Conway March 2008 A redescription of a rare chordate Metaspriggina Walcotti Simonetta and Insom from the Burgess Shale Middle Cambrian British Columbia Canada Journal of Paleontology 82 2 424 430 Bibcode 2008JPal 82 424M doi 10 1666 06 130 1 S2CID 85619898 Tegelaar E W de Leeuw J W Derenne S Largeau C November 1989 A reappraisal of kerogen formation Geochimica et Cosmochimica Acta 53 11 3103 3106 Bibcode 1989GeCoA 53 3103T doi 10 1016 0016 7037 89 90191 9 Behrensmeyer Anna K Kidwell Susan M Gastaldo Robert A December 2000 Taphonomy and paleobiology Paleobiology 26 103 147 doi 10 1666 0094 8373 2000 26 103 TAP 2 0 CO 2 S2CID 39048746 Kammerer Christian F Deutsch Michol Lungmus Jacqueline K Angielczyk Kenneth D 2020 10 07 Effects of taphonomic deformation on geometric morphometric analysis of fossils a study using the dicynodont Diictodon feliceps Therapsida Anomodontia PeerJ 8 e9925 doi 10 7717 peerj 9925 ISSN 2167 8359 PMC 7547620 PMID 33083110 Liu Alexander G Mcilroy Duncan Antcliffe Jonathan B Brasier Martin D May 2011 Effaced preservation in the Ediacara biota and its implications for the early macrofossil record EDIACARAN TAPHOMORPHS Palaeontology 54 3 607 doi 10 1111 j 1475 4983 2010 01024 x S2CID 128785224 Retrieved 20 February 2022 Sorg Marcella Haglund William 2001 07 30 Advancing Forensic Taphonomy Purpose Theory and Process Advances in Forensic Taphonomy CRC Press pp 3 29 doi 10 1201 9781420058352 3 ISBN 978 0 8493 1189 5 retrieved 2022 04 11 Pokines James T Symes Steve A L Abbe Ericka N eds December 2021 Manual of forensic taphonomy CRC Press pp 115 134 ISBN 978 0 367 77437 0 OCLC 1256590576 Further reading EditEmig C C 2002 Death a key information in marine palaeoecology Current topics on taphonomy and fossilization Col lecio Encontres Vol 5 Valencia pp 21 26 ISBN 9788484840367 OCLC 49214974 a href Template Cite book html title Template Cite book cite book a CS1 maint location missing publisher link Greenwood D R 1991 The taphonomy of plant macrofossils In Donovan S K ed The processes of fossilisation Belhaven Press pp 141 169 Lyman R L 1994 Vertebrate Taphonomy Cambridge University Press doi 10 1017 CBO9781139878302 ISBN 9780521452151 Shipman P 1981 Life history of a fossil An introduction to taphonomy and paleoecology Harvard University Press ISBN 0674530853 Taylor P D Wilson M A July 2003 Palaeoecology and evolution of marine hard substrate communities PDF Earth Science Reviews 62 1 2 1 103 Bibcode 2003ESRv 62 1T doi 10 1016 S0012 8252 02 00131 9 External links EditThe Shelf and Slope Experimental Taphonomy Initiative is the first long term large scale deployment and re collection of organism remains on the sea floor Journal of Taphonomy Bioerosion Website at the College of Wooster Comprehensive bioerosion bibliography compiled by Mark A Wilson Taphonomy Minerals and the Origins of Life Robert Hazen NASA video 60m April 2014 7th International Meeting on Taphonomy and Fossilization Taphos 2014 at the Universita degli studi di Ferrara Italy 10 13 September 2014 Portals nbsp Astronomy nbsp Biology nbsp geology Retrieved from https en wikipedia org w index php title Taphonomy amp oldid 1173268911, wikipedia, wiki, book, books, library,

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