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

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:

Archaeobotany

Archaeology

Biology

Forensic science

Geoarchaeology

Geology

Paleoecology

Paleontology

Zooarchaeology

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

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
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. In the marine
environment, taphonomy, specifically aragonite loss,[16] poses a major challenge in reconstructing
past environments from the modern,[17] notably in settings such as carbonate platforms.

Forensic science

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.[18]

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.[19]

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.[20]

Archaeology

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.[21] 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.[22] 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.[23] 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.[24]

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.[25]

Taphonomic study of the Taung child skull claims they were likely killed by a large bird, indicated by
traces of talon cuts.[26]

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.[25] 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.[25]

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.[25] In practice John Speth applied
these 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.[27]

One of the most important elements in this methodology is replication, to confirm the validity of
results.[21]

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.[25] 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.[21]

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