Forensic Entomology Forensic Entomology Name Class Date Professor Forensic Entomology Forensic entomology is the study of bugs in the criminal justice field in order to determine the post mortem interval (PMI). The post mortem interval refers to the time between a person dies and the body of the deceased is located. In criminal cases understanding when a person died can point to suspect or causes suspects in the case to be discarded. When a person dies bugs will be immediately be attracted to the decaying body. There are many factors that can affect the rate of decomposition affecting the PMI. The lifespan of these bugs as well as their activity provides reliable information on time of death. The blowfly is an important insect for determining the post mortem interval. The lifecycle of the blowfly located in the decomposing body can point to how long the person has been dead. Once a person dies blow flies will immediately begin to feed of the body and lay their eggs in moist areas where their eggs will thrive. The blow fly will lay up to 250 eggs in the moist opening. The eggs will look like little small white sausages that are all laid together in clumps. These eggs will hatch within twenty four hours after being laid by the blow fly. Once the blowfly hatches it becomes larvae. After hatching, the larvae will undergo three stages of development, lasting a combined total of 7 to 10 days (Smith, 2011).The newly hatched larvae (maggots) are in the first stage. The maggots become longer and more elongated shaped. The maggot has small hooks by the mouth that help them move or to latch on the corpse and feed. These shape and size of hooks will help determine the type of fly. Theses maggots will feed until they become second stage maggots. A part of this process is to leave the moist area on the decaying body finding a dryer place in which to turn to pupae. This is the third stage of the maggot. The pupae are different from the other maggot forms because a harder outer shell develops. During this process the actual insect takes form within the pupae developing legs and wings. This fly is completely white until the pupae splits revealing the blow fly. When looking for pupae many are found around the body and not directly on the body due to the fact they need a dry place in which to mature. The temperature and moisture can affect the length of each stage of the blowfly development. The number of eggs laid by blowflies can result in large masses of maggots in the body which in turn can affect the body temperature of the body. When determining time of death the temperature of the body plays an important role if the death is relatively soon before locating the body. Masses of third-stage maggots may produce heat, which can raise the temperature around them more than 10° C. (Smith, 2011). Overtime the pupae will open and a full grown blow fly will emerge from the shell. Determining the time of death is more precise if the.

1. Forensic Entomology
Forensic Entomology
Name
Class
Date
Professor
Forensic Entomology
Forensic entomology is the study of bugs in the criminal justice
field in order to determine the post mortem interval (PMI). The
post mortem interval refers to the time between a person dies
and the body of the deceased is located. In criminal cases
understanding when a person died can point to suspect or causes
suspects in the case to be discarded. When a person dies bugs

2. will be immediately be attracted to the decaying body. There are
many factors that can affect the rate of decomposition affecting
the PMI. The lifespan of these bugs as well as their activity
provides reliable information on time of death.
The blowfly is an important insect for determining the post
mortem interval. The lifecycle of the blowfly located in the
decomposing body can point to how long the person has been
dead. Once a person dies blow flies will immediately begin to
feed of the body and lay their eggs in moist areas where their
eggs will thrive. The blow fly will lay up to 250 eggs in the
moist opening. The eggs will look like little small white
sausages that are all laid together in clumps. These eggs will
hatch within twenty four hours after being laid by the blow fly.
Once the blowfly hatches it becomes larvae.
After hatching, the larvae will undergo three stages of
development, lasting a combined total of 7 to 10 days (Smith,
2011).The newly hatched larvae (maggots) are in the first stage.
The maggots become longer and more elongated shaped. The
maggot has small hooks by the mouth that help them move or to
latch on the corpse and feed. These shape and size of hooks will
help determine the type of fly. Theses maggots will feed until
they become second stage maggots.
A part of this process is to leave the moist area on the decaying
body finding a dryer place in which to turn to pupae. This is the
third stage of the maggot. The pupae are different from the
other maggot forms because a harder outer shell develops.
During this process the actual insect takes form within the
pupae developing legs and wings. This fly is completely white
until the pupae splits revealing the blow fly. When looking for
pupae many are found around the body and not directly on the
body due to the fact they need a dry place in which to mature.
The temperature and moisture can affect the length of each
stage of the blowfly development.
The number of eggs laid by blowflies can result in large masses
of maggots in the body which in turn can affect the body
temperature of the body. When determining time of death the

3. temperature of the body plays an important role if the death is
relatively soon before locating the body. Masses of third-stage
maggots may produce heat, which can raise the temperature
around them more than 10° C. (Smith, 2011). Overtime the
pupae will open and a full grown blow fly will emerge from the
shell.
Determining the time of death is more precise if the body is
located within one month of death. New cycles of blow flies can
make determining time of death more difficult. The lifecycle of
the blowfly can take up to a month but be as little as ten days to
complete the cycle. The blow fly is an important tool for the
forensic entomologist because they lay their eggs immediately
after death allowing the entomologist to make a determination
of time of death. When time of death is in question samples are
collected in order to be able to make the necessary calculations.
The calculations are based on based on the stage the larvae are
found on a body.
In order to make a determination of death the forensic scientists
will collect samples of bugs at every stage from the body. The
collection of these bugs is not only important to determining the
post mortem interval it also provides other information to the
forensic entomologist. For example if bugs collected from the
body are not from the area where the body was located it points
to the victim dying in another location. Bug life cans also be
tested after feeding on the body to provide information on any
potential substances in the body.
The bugs will be collected carefully applying standardized
forensic methods. The first steps as with any crime scene is to
take detailed notes about the scene locating all potential
evidence including bug life on or off the body. Once the notes
have been taken the evidence will be collected. The collection
process begins with photographing the body and then
photographing the individual bug life that will be collected.
Each bug will be collected carefully and placed in an evidence
envelope to be transported to the forensic lab. Each bug will be
analyzed upon arrival. Once the body is moved bugs under the

4. boy will also be collected.
Blowflies will not be the only bugs attracted to the body so not
only will the blowfly, larvae, and pupae be collected but the bug
life one the body. The collection process requires the forensic
entomologist to pay attention to the type of environment and
any special features in the environment, such as rural or urban,
indoors or outdoors, wet or arid, etc (Warrington, 2010).The
temperature of the body will be taken and the temperature at the
scene. They will also provide specifics about where the body
was located, how it was poisoned, and what direction the body
was facing.
Every single detail at the scene will be used to help determine
time of death. The body farm at the Quantico is used to develop
information on body decaying in every possible condition and
time frame in order to have more accurate information about
time of death. Part of the collection process will be taking
detailed notes on the scene, such as temperature, moisture
levels, etc. to match the information found to the research
conducted on the decomposing body and bug life. The bugs are
an important part of the determination of the post mortem
interval. Without the PMI determining the time of death for a
decomposing body would be impossible.
The type of tools needed to collect bug life at the crime scene
includes a trowel that is used to dig soil samples. The soil will
contain bug life and other chemical from the decomposing body.
A thermometer is brought to the scene by the entomologist in
order to determine the body temperature, temperature of
maggots, and temperature of surrounding environment. Secure
ventilated jars are brought to the scene in order to collect live
bugs. The ventilated jar will ensure the bug survives the trip to
the lab. Each live bug must be placed in a separate jars include
flying bugs.
Flying bugs around the body, such as blow flies, are captured
with a net while tweezers re used to capture crawling bugs.
Each bug and its type will yield important information about the
time of death or even if the body was located at the scene

5. originally. The forensic entomologist will bring a portable
weather station to the scene in order to record weather
conditions. The weather station will be left at the scene for five
days to get an accurate recoding of temperature. Specimen jars
are used to collect dead bugs that are also important to
determining time of death.
After some time other insects will appear on the body. These
insects include the fresh fly that comes after the blow fly then
the coffin fly, the cheese fly, and the skin beetle. The fresh fly
will appear on the body within the first three month (Welch,
2012). If the fresh fly is not present then the body has not been
at the scene for three month. The coffin fly also appears within
the first three months. This only provides a broad timeframe but
if the cheese fly is also present then the body has been at the
scene between three to six months. Skin beetles do not arrive
until the body has been at the scene for over a year. This will
tell the entomologist the death is not recent and the body has
been at the scene for some time. Once a body has been at a
scene for over a year it will take an examination of the bugs and
bones to determine the post mortem interval.

6. References
Smith, E. (2011). Forensic Entomologists Study Insect
Succession at Death Scenes. Retrieved
September 6, 2014 from https://suite.io/erika-lyn-
smith/599s2hk
Warrington, D. (2010). Crime Scene Bugs. Retrieved September
6, 2014 from
http://www.forensicmag.com/articles/2010/10/crime-scene-bugs
Welch, J. (2012). How forensic science (entomology) works:
blow flies, coffin bugs, carrion
beetles on a corpse. Retrieved September 6, 2014 from
http://schatzie-
speaks.hubpages.com/hub/Forensic-Entomology-corpse-
analysis-with-flies-beetles