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Literature Review over the Effect of Textile Material Affecting Forensic Important Insects from
Entering a Body
By
Dustin Stockmann
A paper submitted for ENTO 896 at the University of Nebraska-Lincoln
1
Table of Contents
Abstract............................................................................................................................................4
Introduction......................................................................................................................................5
Taphonomic Research.....................................................................................................................6
Forensic Entomology.......................................................................................................................6
Fabric/textile barriers.......................................................................................................................7
Estimation of the Post-Mortem Level..............................................................................................9
Forensic Entomology and Post-Mortem Interval..........................................................................10
Influencing factors of time since death estimations .....................................................................10
Accumulated degree days (ADD).................................................................................................10
Accumulated degree hour(ADH)...................................................................................................11
Cumulative degree hours (CDH)...................................................................................................11
Stages of tissue decomposition......................................................................................................12
A. rigor mortis........................................................................................................................12
B. livor mortis.........................................................................................................................13
C. Algor mortis.......................................................................................................................13
Fresh Stage.....................................................................................................................................14
Autolysis........................................................................................................................................14
Decay Stage...................................................................................................................................14
Skeletonization Stage.....................................................................................................................15
Factors affecting the rate of decomposition ..................................................................................16
A. temperature........................................................................................................................16
B. moisture.............................................................................................................................16
Insect Activity................................................................................................................................17
2
Arthropods relationship to a body.................................................................................................18
Necrophagous species....................................................................................................................18
Predators and parasites of nectophagous species...........................................................................18
Maggot activity in a body..............................................................................................................19
Omnivorous species.......................................................................................................................20
Adventive species..........................................................................................................................20
A. seasonality..........................................................................................................................20
B. Surface vs. buried bodies...................................................................................................21
Fabric/textile barriers.....................................................................................................................19
Conclusion.....................................................................................................................................22
Work cited.....................................................................................................................................23
Vita................................................................................................................................................26
3
Abstract
There are a large number of factors that can impact the process in which forensically
important insects may enter into a carcass. A main hindrance of insects has been the ability to
access substantially more portions of a body to feed on. This literature review deals with the
accessibility and chance of being able to find an opening to explore if a body has been covered.
Coverings can impact the decomposition process of a cadaver in which are frequently found in
forensics cases (Dautartas, 2009). Depending on which season the carcass is discovered in, can
lead to a possible interference of not only insects being able to access entrance into a body, but
also how this can retard the process of insects entering into the body (Miller, 2002).
4
Introduction
Forensic entomology is a broad field in which arthropods and the judicial system interact.
A forensic entomologist uses the presence of insects as tools of evidence to discover
circumstances of interest to the law as it is often related to crime (Silahuddin, Latif, Kurahashi,
Walter, & Heo, 2015). A problem that must be addressed in the ever-growing field of forensic
science is to establish accurately when a death occurred (Gordon, 2003). This issue of having to
determine postmortem intervals (PMI) is helped by the use of forensically important insects. This
determination uses several different factors in allowing insects to determine PMI due to their
succession on a corpse (Dautartas, 2009). Due to a body possibly being wrapped in some textile
or fabric, this can affect how the insects would effectively access a body. Since a multitude of
factors can affect the decomposition process, coverings for this literature review were based on
the textiles of plastic and fabric because they are the most common coverings observed on
bodies.
This literature review purpose is to: first, assess how different materials covering a body
can affect the entrance of crucial forensics insects into a body. This question focuses on how
individual textiles can hinder forensically important insects from accessing a body. The second
question of this literature review is to help determine how coverings can affect a PMI estimate.
Clothing has different effects on the decomposition of a body based on its material and thickness
(HauTEO, Hamzah, Osman, Ghani, & Hamzah, 2013). The research behind developing this
literature review stands to the current knowledge of how PMI estimates within legal cases can be
affected due to the environment in which they are found. Insect activity is arguably one of the
most important factors influencing decomposition (Dautartas, 2009). Traditionally, a forensic
entomologist who is trying to establish A PMI, first needs to establish the age of the insects,
5
particularly blow fly larvae collected from the corpse (Mohr & Tomberlin, 2014). The age of
these larvae are then applied to either AAH or ADD growth models and calculated using the
accumulated-hour and accumulated day concept of growth (Higley & Haskell, 2001)
Taphonomic Research
Taphonomic research has become more common in forensics work across the world
(Dautartas, 2009). The Field of study regarding taphonomic research examines how the
processes of a biological organism change in the time of death estimates. Such factors as
environmental, biological, chemical, and even cultural factors can affect how matter can be
decomposed. Figuring out these processes can help explain precisely how decomposition can be
affected, and this in turn allows for more accurate estimate of the PMI or time of death. An exact
assessment of PMI can help narrow the carcass of data that will need to be assessed. This overall
helps with creating a timeline for a forensic case.
Forensic Entomology
Forensic entomology is the study of insects in the use of criminal investigations (Joseph,
Mathew, Sathyan, & Vargheese, 2011). The study of insects associated with the human corpse is
an effort to determine the elapsed time of death upon a carcass (Anderson, 2010). Insects being
used as a tool of evidence can assist in determining if a body has been moved, such as, if a
corpse has been moved to a second site after death, or the body has been disturbed either by
animals or the perpetrator returning to the scene of the crime. Insects on and around the dead
body can tell forensic entomologists how long a person has been dead. An entomologist from a
forensically trained program can help to create an approximate estimation to give an estimated
time of death. This is an estimate created from the different types of insects that are found either
6
on, or around the carcass. Proper identification of insects and arthropod species of forensic
importance is one of the most important elements in forensic entomology (Byrd & Castner,
2001).
Fabric/textile barriers
Forensic entomologists and other scientists often attempt to study decomposition rates
and patterns by compiling information gathered from individual forensic cases. These case
studies can then be compared with other similar situations, and commonalities and differences
can be discovered. Anecdotal information also provides a useful starting point for developing
future research topics. Common trends seen in the forensic cases can provide questions that fuel
hypotheses and experimental designs.
The idea to study how clothing, fabric, or textiles affects the decay rate stemmed from
case reports. In a review of forensic anthropology casework in New Mexico, 120 of 598 cases
were reported to include clothed individuals found at the crime scene (Komar, 2003). Although
this seems to be a small percentage of the total number of cases, instances where the individual
was clothed were frequent enough that further study of the effects of clothing would prove
useful. Clothing has different effects on the bodies based by its material and thickness (HauTEO,
Hamzah, Osman, Ghani, & Hamzah, 2013).
Also, not all of the individuals were clothed in the same manner. Seventy-four
individuals were found in light summer clothing while forty-six individuals were dressed in
winter clothing (Komar, 2003).
Clothing also promotes adipocere formation (Miller, 2002). Adipocere can be defined as
7
an insoluble soap formed from fatty acids, which hydrolyze with bivalent ions (Jackowski et al.,
2005). However, the presence of clothing on a surface deposition has been shown both to slow
and to accelerate decomposition, depending upon other factors (Cahoon, 1992, Miller, 2002).
Other types of covering such as plastic bags, carpets and tarps can also affect the decomposition
rates of buried bodies in a similar fashion. For example, plastic bags have been observed to
increase adipocere formation by trapping moisture (Miller, 2002).
Clothing, although possibly the most frequently studied covering, is not the only type of
covering to be reported on a deceased individual. In the same survey of New Mexico cases,
Komar (2003) reported that sixteen individuals were found wrapped in plastic, and twenty were
noted as wrapped in a cloth or blanket. A canvas tarp was found wrapped around another
individual, and two instances were reported in which individuals were located in burlap bags
(Komar, 2003).
Variation in body coverings spans a broad spectrum. A case from Singapore involved the
remains of a child found wrapped in nine layers of plastic and then placed in a plastic bag (Chui,
2006). In this instance, the body was reportedly in a state of much higher preservation than
expected for the hot, humid climate (Chui, 2006). Again, this illustrates how coverings can
dramatically affect the estimation of post mortem interval. Individuals are sometimes responsible
for their own placement in odd coverings. One suicide report detailed how an individual wrapped
himself in a large plastic bag and then connected plastic tubes between the bag and two gas tanks
(Piatigorsky, 2006).
Manhein (1997) discusses several case studies from Louisiana that she had examined. In
one of these cases, a body had been deposited in a plastic bag, which appeared to preserve the
8
body. A second case study had a woman wrapped in a polyester mattress cover, which did not
seem to preserve the remains. Still a third case introduced another type of fabric; a man was
wrapped in a vinyl tablecloth prior to disposal (Manhein, 1997). In a survey conducted of eighty-
seven cases, fifty-four of the bodies were wrapped in some type of fabric prior to burial. Plastic
was one of the most common fabrics, but a wide variety was noted, including rugs, sleeping
bags, blankets, and clothing (Manhein, 1997). Another instance of unusual deposition happened
in Virginia. A man murdered his wife and buried her charred remains wrapped in a carpet
(Glassman, 2003).
Light clothing amplifies decomposition by protecting maggots from sunlight, rainfall, and
other hazards from the world (HauTEO, Hamzah, Osman, Ghani, & Hamzah, 2013). This
covering creates a potential importance of how a body will decompose. Kelly, Van Der Linde,
and Anderson (2009) demonstrated that carcass wrapping is of clear importance, as it results in
larger, more visible and more freely moving larval masses, longer duration of advanced decay
and more biomass remaining after termination of active decay. However, clothing (considered in
isolation) was found to be of no importance, since control and clothed carcasses decomposed
with the same pattern and rate as control and unclothed carcasses
Estimation of the Post-Mortem Level
The post-mortem level can be affected by various factors such as temperature, moisture,
and the carcass chemical content. Forensic entomologist collect samples from on and around the
carcass. These may be eggs, larvae or maggots, pupae and/or empty pupal casings, as well as
adults (Anderson, 2010). In order to build a timetable that is usable, there must be enough data
collected to help establish the post-mortem level.
9
Forensic Entomology and Post-Mortem Interval
Over a span of the last few decades, more studies have been conducted trying to figure
out which species of insects help with providing PMI the best. Insects including flies, beetles,
and moths have been able to provide the most accurate description of figuring out PMI. This
research conducted has been looking at the amount of activity that insects will put into trying to
access a carcass after death. Being able to identify the insects correctly that are present at a death
scene, and being able to determine where the insects are in their life cycle can help to create an
accurate time of death estimate.
Influencing factors of time since death estimations
There are many ways that influence how to figure out the time of death of an individual.
This comes from the amount of a body mass that has been lost due to the blow fly larvae during
the first few days when decomposition has set in. It is possible for the blow fly larva to remove
up to 60% of the body mass in a relatively short period (Greenberg & Kunich, 2005). With the
loss of soft tissue, forensic entomologist investigators may come up with a much longer time
than what is accurate due to the blowfly behavior. Other insects that may traumatize the remains
during the different stages of decomposition can include bees, wasps, ants, lice, and cockroaches.
Knowledge of these insects’ different types of behavior can allow forensic entomologist
investigators a chance to determine PMI more accurately from a body (Dautartas, 2009).
Accumulated degree days (ADD)
Accumulated degree days (ADD) is a term that is used to help establish a time in the
number of days since death or the accrued total hours since a death has occurred. Recently
accumulated degree days has become increasingly more prevailing as a standardized unit of
10
measurement for postmortem intervals (Dautartas, 2009). There are limitations that exist with
this method due to the basic principle is that this correlation is linear between temperature and
development (Anderson, 2000). Since insect development is heavily influenced by temperature
such as temperature extremes, ADD was established to help align certain stages of development
with a range of differing temperatures within extremes. Since temperature extremes can affect
how accumulated degree days can be determined, this method only requires that an individual be
aware of how the temperatures can affect the overall development and could require less
calculation of accumulated degree days (Dautartas, 2009).
Accumulated degree hours (ADH)
Since there’s been an increased frequency of the use of the accumulated degree days in
entomological research and application, this is prompted entomologist to expand and refine the
concept of ADD. Accumulated degree hours (ADH) is the response to this which was first
established in agricultural studies (Greenberg & Kunich, 2005). ADH was originally developed
to help find the time that was best for insecticide application to help limit the damage that in
agricultural pest could provide to crops. ADH is also assumed as a linear relationship between
temperature and insect development overall. To determine the total ADH for an insect
maturation requires an individual to add the number of hours from eggs to adulthood. Next the
researcher will multiply them by the quantity of the temperature in degrees Celsius after
subtracting the total developmental threshold temperature (Greenberg & Kunich, 2005).
Cumulative degree hours (CDH)
Cumulative degree hours refines the concept further of establishing intervals for
establishing when death occurred. For the possibility of having a body decomposing for many
11
months, the estimation of accumulated degree days may not be critical to impact the case work.
Being able to narrow down the technique is much more beneficial when determining the
decomposing rate of a body that has been dead for a shorter amount of time (Dautartas, 2009).
To calculate CDH the average temperature in degrees Celsius is added for each twelve hour
interval that the body is in a decomposing process (Vass, et al., 2002). Measuring temperatures at
a smaller interval allow for a greater accuracy to happen. The limit to this technique in cases in
which a body has not been decomposing for a long period.
Stages of tissue decomposition
The decomposition of a body will happen in a very predictable pattern depending on
temperature, moisture, and climate. The research has tried to describe and define how each stage
is and its total length, at controlled conditions. There are many factors that may change how a
body will decompose, but it will still follow a standard set of stages. These stages are called:
rigor mortis, livor mortis, and algor mortis. During the beginning of death, the fresh stage of the
soft tissue, decomposition will take place. This is normally within the first 24-48 hours following
death (Galloway, Birkby, Jones, Henry, & Parks, 1989).
Rigor Mortis
Rigor mortis is the process in which muscles in the body will stiffen due to an increase of
lactic acid in the tissue following death (Hunter, Roberts, & Martin, 1996). Eventually, what will
happen is all of the muscles will seize, and the body will become unable to move from its
position. This will begin within 2-4 hours after death has taken place and its peak around the 12
hour mark after death has occurred. Rigor mortis is affected by both the body temperature and
metabolic rate of the body before death.
12
Livor Mortis
Livor mortis is the next process that is used to describe a post-mortem interval (Kaatsch,
Schmidtke, & Nietsch, 1994). When the cells of a body break down, and circulatory activity has
ceases, blood will respond to the effect of gravity and settles in the lowest points of the body.
This settling creates visible, red areas on the skin of the body (Baden & Hennessee, 1990).This
process, although affected by other variables, begins within an hour post mortem and takes
around eight hours to complete (Baden & Hennessee, 1990). Additionally, if a body is moved
after a period of time, the lividity will be fixed. This fixing of the lividity creates “stains” that
are noticeable at the site of original contact. The blood that has not pooled in the body will not
move out of the body unless the body has been punctured where the blood has pooled.
Therefore, this can be helpful in determining not only post mortem interval, but if the body is in
its primary or secondary placement (Kaatsch, Schmidtke, & Nietsch, 1994).
Algor Mortis
This is described as when the body has died, and the temperature drops two degrees
within the first twelve hours after death and continues to fall at a constant rate of about one
degree per hour (Kaatsch, Schmidtke, & Nietsch, 1994). Simple calculations are then needed to
determine the time since the death has occurred. The issue with these calculations are that
temperature can be affected by the ambient temperature and bacterial activity (Dautartas, 2009).
These processes can be used to create an approximation of a time since the death that is precise
to a few hours. All the same, these techniques will stop to be effective at around the thirty-six
hours post mortem. The need to develop a time table for this process later in the decomposition
stage, needs to be assessed.
13
Fresh Stage
This is the first stage of death and will continue until the body has started to show
evidence of bloating (Goff, 2010). During this stage there are a few decompositional changes
that happen with the body, such as, color changing of the abodomen and livor and the skin will
start to crack. Generally insect intrusion of a body will happen with any opening that is possible
such as the head, anus, and genitals or if there is a wound present.
Autolysis
During the process of decomposition, when the carcas is no longer considered in the fresh
phase, this is when autolysis occurs (Dautartas, 2009). Autolysis is a name given to the cell death
that results in a complete loss of cellular integrity and widespread necrosis (Parsons, 2003). The
stopping of circulatory activity and the resulting loss of adenosine triphosphate (ATP) causes a
chemical change in the cell wall and a mixing of the extracellular matrix and the surrounding cell
tissue (Dautartas, 2009). This process of cell death then leads to a drop in the pH of the
cytoplasm as cellular death continues within the body. Within the cytoplasm, the enzymes
become active and continue to process the deterioration of the cellular material. On the outside of
the body, massive color change is evident in the skin complexion, which will become paler, and
skin slippage is often observable (Vass et al., 2002).
Decay Stage
This stage , the decay consists chiefly of increased and intensive interior decomposition
reactions. The skin cracks, and eventually decomposer, along with other microorganisms enter
into the soft tissues of the body (Galloway, Birkby, Jones, Henry, & Parks, 1989). This stage is
when the activities of the maggot feeding and bacterial putrefaction have reached critical mass
14
and the skin starts to break down. This is the point of when the bloating of the body will start to
retard back due to escaping gasses. As the internal tissue becomes exposed to the environment,
this opening will allow oxygen to enter in, progressing the rate of decomposion. This increases in
the aerobic bacterial activity, which accelerates tissue decomposition (Rodiguez, 1982). The
feature that helps explain further insect involvement is the presence of large feeding masses of
Diptera larvae (Goff, 2010). As the body is splitting open due to the pressure of the putrefaction
and maggots producing heat, the maggots will spill out onto the ground around the body. These
Diptera larvae will remove most of the flesh from the body leaving skin, hair and cartilage (Goff,
2010).
Any remaining head hair cast off from the body and forms a “hair mat.” This is a slew of
tangled hair which accumulate below the body structure. Liquid leaking out of the body allows
for the exposure of the skeleton, and the remains of the body begin to dry. As this process starts
to happen, more bone is exposed, leading to the dry stage. As the body starts to dry out, the
Diptera start to cease to be the predominate insect. Varous groups of Coleptera will replace the
Diptera, during this stage of decomposition.
Skeletonization stage
This last process of the decomposition phase includes little or no soft tissue leftover, with
extensive skeletalization evident over the entire body (Rodiguez, 1982). Although there can be a
great deal of variations in the biological processes that lead to the remaining of a skeleton, any
remaining parts after skeletalization is reasoned to be component of the end of the decomposition
process. The skeletonization stage can last for months or years. It is marked only by the ultimate
breakdown of the skeleton its self. Once a body has achieved this phase, determination of time
that has passed since death has occurred can be hard because skeletal preservation will count
15
more on the surroundings. Scavenging, weather conditions, soil acidity, and other factors can all
affect how well bone material remains intact.
Factors affecting the rate of the decomposition process
A multitude of factors can affect each stage of the decomposition process, either
accelerating the process or retarding it, depending on the particular agent at work. Some of the
most frequently observed variables are temperature, moisture, insect activity, and exposure to
either sun or shade. Another factor that can affect activity is if the remains are left on the surface
or have been buried or submerged has an impact on the rate of decay. Normally, many of these
variables affect the decomposition process of a body. The effects of decomposition are seen in
multiple stages. The fact that these influences interact throughout the entire process is what
makes the sequence so variable.
Temperature
Decomposition of a body is affected by the temperature of where the body is at. It is
observed that a trend of warmer climates will promote a faster rate of decay and in a colder
climate, there will be a reduction in the process (Adams & Byrd, 2014).
Moisture
Moisture is a factor that can contribute to the rate of decomposition of a body. An
environment that retains more moisture will aid in decomposition whereas a climate that is
arider, will affect the process by slowing it down (Galloway, Birkby, Jones, Henry, & Parks,
1989). The combination of arid conditions and temperature extremes will provide that the body
will start to become mummified faster. These are examples of how active factors can lead to an
increase in the amount of how fast a body can decompose. The importance of moisture content
16
to decomposition allowed for accelerated water loss and this leads to faster desiccation of tissue
(Saras & Lukasewycz, 1999).
Insect activity
Insect activity is reasoned as one of the most significant factors affecting a body’s
decomposition. Insects quicken the decomposition process by processing different levels of the
body breaking down (Gonzales, Vance, Helpern, & Uberger, 1959). Ants, blowflies, beetles, and
cockroaches all affect the decomposing tissue. Typically, blowflies are the first insects attracted
to the body; they can be observed on a corpse minutes after deposition (Campobasso, Di Vella,
& Introna, 2001). Insects position eggs approximately close to the orifices of the mouth, nostrils,
eyes and genitals, and any open wounds that can be accessed on the body. These eggs then hatch
into maggots within eight to fourteen hours (Campobasso, Di Vella, & Introna, 2001). Insects
can be affected by coverings blocking the entrance to a body as well as where the location of the
body is, in relationship to shade and sun. (Dautartas, 2009). Insects prefer warm protected areas
away from directed sunlight (Miller, 2002).
The succession of these insects come in waves to the body after death that can be
adequately calculated in forming an idea of when did death occur (Mohr & Tomberlin, 2014).
Most research has shown that as the body has started to enter the breaking down phase, blow
flies are the first indication that insects are going to be on the way to begin to decompose the
body. There are also flesh flies (Sarcophagidae) that will appear as soon as the body starts to
break down (Goff, 2010). The female flies will begin to explore any openings for possible
entrance for oviposition or larvipoition. These insects will bore into any opening and deposit
eggs, 1st instar larvae or maggots. These openings to the body are affected by if they are covered
17
or not such as by cloth or another textile material (Goff, 2010).
Arthropods relationship to a body
In the decomposition of a body, there are many different relationships that arise as the
body changes (Goff, 2010). As a body decomposes, there are four different stages of species that
will approach the carcass. These four stages of species are: I) necrophagous species, II) predators
and parasites of necrophagous species, III) omnivorous species, and IV) adventive species.
Within these different population of species that will come to a body, not all will have the same
role (Goff, 2010).
Necrophagous species
These are the species of insects that are actually feeding on the corpse. This group
includes many of the true flies (Diptera), including the blow flies (Calliphoridae), and the flesh
flies (Sarcophagidae) who are the first to arrive on a body after death. The next important insects
to arrive are the beetles (Coleoptera: Dermestidae, and Silphidae) who are important for use in
figuring out the minimum period of activity on a body. The last group of insects, the Acari, are
not too involved in this stage but start to show up (Goff, 2010).
Predators and parasites of necrophagous species
This next significant group of taxa that attacks a corpse are the most significant because
they will visit the body the most. Many beetles (Coleoptera: Histeridae, Silphidae, and
Staphylinidae), the true flies (Diptera: Calliphoridae and Stratiomyidae), and wasps
(Hymenoptera) who are parasitic on the fly larvae and pupae are included in this list. Certain
18
species of fly larvae are necrophages during their early developmental stages of life in which
they must have the carrion to survive (Goff, 2010).
Maggot activity in a body
As the maggots mature, they disrupt the soft tissue, burrowing into the flesh. The larvae
also decompose proteins in the soft tissue, which leads to liquefaction of the area (Evans, 1963).
Large numbers of maggots are cultivated in the body, and this collective group is often capable
of damaging much of the soft tissue within a short period of time. This focal liquefaction of the
body helps the maggots travel throughout the body. Also, as the maggots travel throughout the
body, they help to disseminate bacteria while feeding (Lord, 1990). The natural process of the
maggot mass also creates heat within the body, which further stimulates decomposition (Mann et
al., 1990). Insect activity rates are variable depending upon ambient temperature and on sun or
shade exposure. Direct sunlight leads to more rapid insect succession but smaller populations,
while shady areas typically exhibit larger insect populations, but slower onset (Srnka, 2003).
With the increase of eggs, 1st instar, and larvae being deposited into the body, and the
heat increases due to the body beginning to digest the tissue, the bloated stage begins. This
combination of putrefaction and metabolic activity of the maggots can increase the body
temperature significantly compared to the surrounding ambient temperature (Goff, 2010). This
combination leads to a perfect combination of a maggot habitat.
This habitat can be changed due to the amount of clothing that is surrounding the body.
Clothing made of cotton or other natural materials are susceptible to microorganism degradation
while artificial polyester clothing is resistant to degradation. These different types of clothing can
19
either enhance or hinder the habitat that maggots would enter for completion of the life cycle
(HauTEO, Hamzah, Osman, Ghani, & Hamzah, 2013).
Fly eggs are normally deposited on a corpse once the death has occurred, determining the
age of the immature insects specimens. Sometimes maggots are found, but no corpse is located.
This association between corpse and maggots can be exceptionally significant (Zehner, Amendt,
& Krettek, 2004). In the cases of sexual assault, the masses of maggots activity could produce
changes that mimic the position of where clothing is currently, compared to where it was. This
clothing position can change daily due to the masses of maggots in the corpse until the body has
had an exodus of the maggot mass (Miller, 2002).
Omnivorous species
There are taxa such as wasps, ants, and some beetles that feed on the corpse and
arthropods that are on and around the corpse. Goff (1986) watched as large populations of these
taxa attack not only the body, but also the other insects causing a slowing in the rate of
decomposition from necrophagous species. Ants typically feed on the epidermis, which allows
the dermis beneath to dry and crack (Miller, 2002).
Adventive species
This final category includes insects that use what is remaining of the corpse as an
expansion of the normal habitat. This is common for centipedes, millipedes, spiders and
springtails (Collembola) (Goff, 2010).
Seasonality
Fly species are also constrained by season (Greenberg & Kunich, 2005). Blowfly species
20
will only appear during the summer months, while others favor cold weather. This information
can also be of importance in determining both the time since death has happened and possible
relocation of the body. The usefulness of seasonality data can be complicated by the fact that
bodies can be moved indoors, with artificial temperature settings that can frequently harbor out
of season insects within the body. Abnormal weather, such as heat waves or cold spells, can also
bewilder the seasonality data. Sometimes a shift in temperature leads normally diurnal flies to
become more active at night, or to less frequent breeding of a species (Greenberg & Kunich,
2005).
Surface vs. buried bodies
Whether remains are deposited on the surface or buried greatly affects decomposition.
Burial of remains inhibits both insect and mammalian scavenging activities and therefore, can
delay decomposition. Also, temperatures above ground are higher than below the surface
(Galloway, Birkby, Jones, Henry, & Parks, 1989). Burial of a body generally shields the remains
from weathering activities, which damage the tissue. The depth of burial also factors into decay
rates and how insects can reach the bodies. As a general trend, a deeper interment will provide
better preservation of remains, due to more stable temperatures and better protection from
surface factors (Adams & Byrd, 2014)
The burial of bodies can make finding of bodies more difficult. Which results in bodies
being interred for a longer period of time and furthering decomposing prior to being recovered
and analyzed. In an attempt to deal with this issue, Vass et al. (2002) researched how chemicals
released during decomposition and the odors that are emitted are picked up by insects. By
building a database of decompositional odors, the researchers hope to develop a chemical sensor
21
that can detect buried bodies without the aid of cadaver dogs. In order to collect the necessary
data, Vass et al. (2002) conducted research over a year and a half period, and collected chemical
samples from bodies buried in shallow graves.
Conclusion
In conducting this literature review, there has been an argument regarding whether
clothing can affect the acceleration or decomposition of a body and how this relates to insects
being able to access entrance. The results of this literature review has shown that clothing, fabric,
and textile material prevents insects to find a way into a body initially. As a body goes into
further steps of decomposition, insects will make a run for any openings that may arise such as
the bloating stage of the decomposition process. As forensic entomologist are called upon to help
in figuring out the time of death of an individual, it must be considered that the clothing, fabric,
and textile material must be taken into account regarding how to calculate Accrued Degree Days
(ADD) and Accrued Hour Days (ADH).
Clothing affects abiotic conditions of the cadaver, as for example its humidity, amount of
shade, or protection for inhabiting arthropods. Some results indicate that it may increase
abundance and diversity of carrion insects, enlarge dipteran larval masses and make larvae more
freely moving, or prolong the period in which some larval Diptera are present on a cadaver.
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Vita
Dustin Ray Stockmann was born in Farmington, Missouri on October 06, 1986. He was
raised in De Soto and attended elementary and secondary school in the De Soto R-73
School District when he graduated in 2005. Dustin went on to attend college at Jefferson
College in Hillsboro, Missouri and graduated with an Associates of Arts. He then
attended Missouri Baptist University in Saint Louis, Missouri and graduated with a B.A.
in Elementary education in 2010, and a M.S.E. in Curriculum and Instruction in 2012.
Next he attended Washington University and graduated with a certificate of Advance
Science Education. Finally he has attended Lindenwood University and has graduated
with a M.S. in School Administration in 2013, and an Educational Specialist in 2014 in
Educational Leadership. He is currently pursuing a MS at the University of Nebraska-
Lincoln, and a Educational Doctorate at Lindenwood University.
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