BUGS, BONES AND BODIES

Anthropology Entomology, and

Pathology

Manner of Death

• Manner of death is the legal circumstance in

which the death occurred.

• Manner is classified into five

categories: natural, homicide, suicide,

accident, or undetermined, based on the

circumstances surrounding the incident.

Cause of Death

• The reason (“why”)someone dies is called

cause of death. The most important

determination in a violent death is the

character of the injury that started the chain

of events that resulted in death.

• Some common causes of death include

Blunt Force Injury – caused

by a non-sharpened object

such as a bat or pipe.

• Sharp Force Trauma -

weapons with sharp

edges capable of

cutting or stabbing.

• Asphyxia –

encompasses a variety of

conditions that involve

interference with the intake of

oxygen such as strangulation

or suffocation.

• One indicator of strangulation is

petechiae - pinpoint hemorrhaging

often observed in the white area of the

victim’s eyes.

Gunshot Wounds –

estimating the range is the

most important

characteristic to analyze.

• Substance Abuse – can cause death or

complications that lead to death.

Stages of Death

• Time of death (TOD) is often estimated by

evaluating the stage of decomposition in

which the victim was found.

• Rigor mortis – the medical condition that

occurs after death and results in the

shortening of muscle tissue and the

stiffening of body parts in the position they

are in when death occurs.

• Livor mortis – the medical condition that

occurs after death and results in the settling

of blood in areas of the body closest to the

ground. It is called lividity.

• Begins about 2 hours after death.

• Between 2-8 hrs lividity present but if skin

is pressed color will

disappear.

• Permanent after 8

hours even when

pressed.

• Algor mortis – postmortem changes that

cause a body to lose heat.

• Rate of heat loss is influenced by such factors

such as the location and size of the body, the

victim’s clothing, and weather conditions.

• The general rule is that beginning about an hour after death, the body will lose heat at a rate of approximately 1 to 1 ½ degrees Fahrenheit per hour until the body reaches the environmental temperature.

• During an autopsy, other factors can be observed that may indicate the time period in which death occurred. For example, the amount of food in the stomach can help to estimate when a person’s last meal was eaten.

Stages of Bodily Breakdown

• Initial decay – externally, the corpse appears much

as it did in life, but decomposition has begun due

to the actions of “bacteria, protozoans, and

nematodes” already present in the body when it

was alive.

• Putrefaction – Gas formed by the activity of

organisms within the body cause it to swell

and smell.

• Black putrefaction – a bit of a misnomer,

actually, as the characteristic discoloration

of the flesh accompanying this stage may be

blue, green, purple, brown, or black. The

swelling of the previous stage collapses

again as that gas begins to escape. The

swelling decreases, but the smell increases

dramatically.

• Butyric fermentation – tissues and organs

have become fluid, fluid has escaped by a

variety of means, and now the body begins

to dessicate (to dry out). Mold usually

covers some or all of the exterior. A

different odor – not good, but not as “knock

you over and send you gagging” as the

previous one – is noticeable.

• Dry decay – not mummification, but a slow

process of continuous decay, during which

time the tissues continue to rot, dry out, and

shrink until skeletization has occurred.

Forensic Pathology

• Forensic pathology involves the investigation of sudden, unnatural, unexplained, or violent deaths.

• Usually medical examiners or coroners.

• Primary role is to determine cause of death.

• Autopsy – the medical dissection and examination of a body in order to determine the cause of death.

Forensic Anthropology

• Forensic anthropology is a specialty that is

concerned primarily with the identification

and examination of human skeletal remains.

• Skeletal bones are remarkably durable and

undergo an extremely slow breakdown

process that will last decades or centuries.

• An examination of

bones may reveal their

origin, sex,

approximate age, race,

and skeletal injury.

• Closures in the

sutures of the skull

are indicators of

age.

The male skull is rougher

with a large brow ridge and

occipital protuberance. The

female skull is smoother with a high forehead.

• The pelvis is the easiest way to determine

gender. The female pelvis is wider, circular

and tilted outward. The male pelvis is

narrow, noncircular and tilted inward.

Forensic Entomology

• The study of insects and their relation to a

criminal investigation.

• By determining the most developed stage of fly

found on the body, entomologists can approximate

the postmortem interval (PMI).

• Postmortem interval (PMI) - the length of time

that has elapsed since a person has died.

Blowflies

• Blowfly eggs are laid in human

remains and ultimately hatch

into maggots that consume human

organs and tissues.

• Life cycle progresses from egg to first instar (a

stage of larval growth, usually determined by

maggot size and how often it has shed its skin)

larvae, to second instar larvae, to third instar

larvae, to prepupae, to pupae within puparium, and

on to imago.

• The length of each stage is dependent on

environmental conditions.

• Before determining how long a body has

been dead, the entomologist must first have

a good idea of when the first blowflies

arrived and laid eggs on the body.

• Blowflies are not native to all areas so other

species are also studied so that experts can

discover their cycle.

Other Bug Notes

• An entomologist must be familiar with the

insects of the region where a body was

found or where death occurred - not

necessarily the same place.

• Photographs should include adult insects of

all species in the vicinity, evidence of insect

activity in any standing blood, and the

remains of insect activity.

• Body parts showing insect infestation need

photographing before the body is removed.

• Air temperatures at ground level, about 5

feet high, and ground surface temperatures

under the body should be recorded.

• Live-specimens, remains, and preserved

samples of all insects should be collected.

• Documentation of the scene must be

included.

• Lack of insects or nonnative insects should

also be recorded.

• Weather data allows entomologists to adjust

life cycle equations.