Unit 14 A - Archaeology & Anthropology
Describe the role of Forensic Anthropologists and Archaeologists in a Forensic Investigation:
The roles of forensic anthropologists
Forensic anthropologists are experts in the study of human remains. Specialising in
examining remains to identify Ante-Mortem, Perimortem and Postmortem injuries to the
remains. Forensic anthropologists are experts in building a biological profile of the remains,
to identify the person's stature, gender, age and ancestry. Additionally, they can provide
information on trauma to the body. There are many pieces of equipment which help assist
the analysis of bones. Often, forensic anthropologists will carry out these processes when a
grave or remains are discovered and believed to be suspicious. They will work alongside
many other agencies, especially law enforcement organisations.
Tools of forensic anthropologists
In order to correctly analyse remains, forensic anthropologists use many devices to assist
their examination processes. Particularly, forensic anthropologists will use Callipers, a
device used to measure bones. The calliper has two components, one end has a hinge, to
clasp the bone under examination. The other component is the attached ruler to the main
body, a reading of the length measured will be identified. Callipers are a calibrated and
accurate piece of equipment, so are a precise tool used to measure the stature of remains.
Another piece of measuring equipment is Anthropometers, a tool to measure limbs and the
torso of human remains. This device has two horizontal arms, one of which can be moved,
the other is fixed. It is then connected to a vertical rod. The moveable component has a ruler
attached to read the measurement required. Similar to callipers, anthropometers are fairly
precise and accurate.
Forensic anthropologists use many tools, hammers and drills are most commonly used.
Hammers are tools with a wooden handle and a metal head. They are usually used to break
objects. However, forensic anthropologists use them to discover what piece of equipment
was used to cause trauma to bone. Drills are used to access the bones bone marrow, this
allows for DNA profiling of the mitochondrial DNA found.
Cutting tools like knives and electrical surgical bone saws can be used to cross sections of
bone. This allows the anthropologists to examine internal deformities inside the bone
(osteoporosis etc).
Identification of human & non human skeletal remains
Discovered remains can be found disarticulated or partial or completely articulated. Unless
you are skilled in identification, it can be difficult to confirm if the remains are animal or
human. In studying the remains, which have been discovered, under the microscope, a
trained individual can determine the origin of the bones, such as human or animal. If the
bones are determined to be animal, it can easily be suggested that a crime was less likely to
have occurred. In many circumstances, there is a noticeable difference between human and
,animal bones. However, human infant bones, due to their small size, can easily be mistaken
for animal bones. By identifying the shape and size of the bones, it can make identification of
the remains easier.
Bone is made up of osteons, they carry blood supply around the body. Animal bones have
an arranged, regular osteon pattern, whereas human bones have an irregular pattern. There
are many features which can differentiate animal remains and humans. For example, the
radius and the ulna in the human skeleton are separated. In an animal skeleton, the radius
and ulna are fused to one another. This fusion of bones allows strength and flexibility in
relation to weight bearing within the animal skeleton. Another difference between human and
animal bones is the cranial vault. A human skull will have a large or bulbous cranial vault, but
a smaller face. Whereas the animal skull will have a small cranial vault and a large face,
often elongated vertically. Lastly, the sacrum in the skeletons. Within the human skeleton,
the sacrum has five fused vertebrae, attached to it, they are noticeably short and broad.
Whereas, with animal skeleton, the sacrum is fused with only three or four vertebrae, which
are noticeably long and narrow.
An osteoprofile’s accuracy is dependent on the preservation and completeness of skeletal
remains, along with the context of the burial. In order to begin an osteo profile, the
anthropologists must identify the bones which are present. Additionally, they need to
determine how many of each bone is present and determine if one or more skeletal remains
are represented when the skeleton is reassembled. To do this, the preservation and
completeness of the bones is crucial knowledge. To complete an inventory, the skeletal
remains will be laid out in their anatomical position. Therefore, an inventory of the bones can
be produced. Often, to produce the bone inventory, a written and diagram representation will
be made.
Along with this, the anthropologists must determine the skeletal completeness. In order to
confirm this, an estimation of the skeletal proportion will be made, remains can be both
completed, or incompleted. However, other factors can affect the accuracy of skeletal
estimation, as the remains can be fragmented, poorly preserved or severely damaged.
Assessment of the number of individuals
Forensic anthropology studies human skeletal remains which hold medicolegal significance,
meaning the remains are believed to be of a missing person, or recent crime. Articulated
remains is a sign that the person died at the location where their bones were found.
However, when the bone fragments appear not articulated, it indicates that the remains were
moved after the death and decomposition of the person. The process of identifying remains
follows a strict process. An inventory of the remains must be made and confirmed as human,
in order to determine the minimum number of individuals, the biological profile, and cause of
death.
MNI is used in commingled cases. It can be calculated by creating a bone inventory and
sorting them by type and size. Therefore, it can be determined which bone is most frequently
seen for example, 3 femurs on the left side indicate 3 individuals. This value can then be
confirmed as the minimum number of individuals (MNI).
, Additionally, the Lincoln Index can be used. This method applies with complete and well
preserved remains. The long bones are sorted based on their directional positioning (left or
right positioning). Once these bones have singularly been sorted by their direction, the
matching limb will be paired. To calculate the number of individuals uses LI = L x R/P.
L: is the total number of left bones from a single element
R: is the total number of right bones from a single element
P: is the total number of limb pairs for that element.
Biological profile
The analysis of remains must have components of the person's biological profile. These
components include their age, gender, ancestry and stature. In infants, children and
adolescents, their growth and development is more predictable than adults, so age at death
estimation is more precise. However, in adults, age estimation is determined by any changes
of the skeleton, so estimating their age interval is broader. For subadult remains, determining
their age can be confirmed by analysing the tooth formation, presence or permanent and
deciduous teeth, their bone length, stage of bone formation.
Analysing the teeth is very useful when identifying children, the stages at which the teeth
have erupted from the gums can indicate a child's age to the year. If the individual is an
adult, it can be determined what age they are, as to how worn down the teeth are from
chewing.
Teeth begin to develop before birth, growing until 18-21 years of age. During the third year of
life, most infants' deciduous teeth emerge, and between 6-8 years of age, is where children's
permanent molars begin to develop. Premolars, canines and second molars develop during
the early stages of adolescents, between 10-12 years of age. So, by observing the remains,
tooth formation, and presence of specific teeth, can assist in estimating the age of the
remains much more accurately.
In some circumstances, a tooth may be unavailable, so by analysing the length and stages
of bone fusion can indicate the person's age. The bone length of subadults can be
determined when measuring the diaphyses length. The ends (epiphyses) mustn't be
accounted for the length, as in children, the skeletal development hasn’t fully occurred, so
the epiphyses are not yet fused to the end of the bones. Once the diaphyses has been
measured, it can be compared to data of known ages of subadults, to determine the most
accurate age at death estimation. However, this technique is less useful when analysing
adult remains, as the size and shape of their long bones will vary more. It is clear that
remains of a person whose diaphyses and epiphyses have not fused together are either
infant or child remains. So, for a young adult (pre teen and teenager), will have partially
fused diaphyses and epiphyses. It is clear that those which are fully fused, will be adult
remains.
Whilst this is useful, the age of certain bone fusion will vary per bone. For example, the
medial clavicle is known to fuse when the person is between 18-25 years of age, so if
