The art of identification

I hope you didn’t miss us too much, but if you did, no worries as we’re back for week 2 of the assignment!

Before we get on to question 4,why don’t we do just a quick run through on what is forensic anthropology really about

Anthropology is the scientific study of the origin, the behavior, and the physical, social, and cultural development of humans.

Forensic anthrolopology
Forensic anthropology is the application of  anthropology to criminal investigations.
Identifying unknown individuals is a key part of forensic anthropology.
Anthropologists assist in identifications primarily by constructing a biological profile. This includes estimating age, sex, stature, and ancestry, as well as identifying specific characteristics, like diseases or injuries.

Lets get on to question 4 then,

In question 4, we were asked to identify the victims using the evidence discovered so far, however we were told not to use the dental aspects provided.

As mentioned above, using methods of forensic anthropology on the evidence that was found, we can identify various characteristics of the victims such sex and race

-The race of the adult victim can be determined by examining certain parts of the skull, such as the openings in eye and nose in the skull that vary among different races.

-The sex of the adult victim could easily be determined by the skull of the victim, ie my examining the general appearance, supra orbital ridges, orbits, glabella, zygomatic arches, mastoid process , palate, forehead,external occipital protuberances as well as the mandible.  (how to differentiate between male and female using these aspects of the skull were explained in Question 2 of part 1 of the assignment )

-The sex of the other victims could also be determined by examining the pieces of jaw (mandibles) that were found.


Forensic facial reconstruction

Forensic facial reconstruction techniques could also be used for identification of the adult victim.

(Forensic facial reconstruction is the process of recreating the face of an individual (whose identity is often not known) from their skeletal remains)

This is because both the skull and pieces of the jaw of the adult victim have been found, and hence features like

• The brow ridge 
• The distance between the eye orbits
• The shape of the nasal chamber
• The shape and projection of the nasal bones
• The chin's form
• The overall profile of the facial bone

Of the adult victim could be used to identify the adult victim’s facial appearance.

DNA profiling
DNA profiling could also be a method of identification of the victims. Samples of DNA of the victims can be obtained from the bones and be used to identify the victims. The DNA is then subjected to polymerase chain reaction (PCR), where it mimics the biological process of DNA replication, but confines it to specific DNA sequences of interest. After a convoluted process involving activation of DNA, denaturation, annealing, and elongation, the specific sequence will be accumulated in billions of copies.

While a lot of DNA contains information for a certain function, there is some called junk DNA, which is currently used for human identification. At some special locations (called loci) in the junk DNA, predictable inheritance patterns were found to be useful in determining biological relationships. These locations contain specific DNA markers that DNA scientists use to identify individuals. In a routine DNA paternity test, the markers used are Short Tandem Repeats (STRs), short pieces of DNA that occur in highly differential repeat patterns among individuals.

Each person’s DNA contains two copies of these markers—one copy inherited from the father and one from the mother. Within a population, the markers at each person’s DNA location could differ in length and sometimes sequence, depending on the markers inherited from the parents. 

The combination of marker sizes found in each person makes up his/her unique genetic profile. When determining the relationship between two individuals, their genetic profiles are compared to see if they share the same inheritance patterns at a statistically conclusive rate.

In the shoes of a forensic expert

Thus, its now time to move on to question 5

In question 5, we were first asked to list out the evidences that have been presented to both doctors so far

The evidences that have been presented so far are:

1) An adult skull with fragmented jaw pieces bearing five teeth.
2) A child’s jaw with erupting teeth (Mixed dentition)
3) A single piece of jaw with three posterior teeth.
4) Soil sample where the remains are found.


Hence it might be safe to assume that there are 3 separate victims at this point in time

In the following part of question 5, by considering the evidences put before us at this point in time, we were asked how we would investigate further, and what we would anticipate during the process

Identification of victim
Our first priority would be to identify the victims as soon as possible by making the best use of the evidence and technology at our disposal.

So how would we carry this out?

DNA 
First, we would then obtain samples of DNA from the bones of the 3 separate victims, followed by getting samples of DNA from family members of the people in the missing peoples list. We would then match these samples together and try to get a match. If a match is found, we would be able to have a direct identification of the victims.


In the meantime, we would consider the dental aspects that were discovered,


Dental Aspect
Based on the dentition and size of the jaw, we can already determine whether the jaw belongs to an adult or a young child and have a rough estimate of their ages.

We would then carry out an orthopantomogram (OPG) to get radiography of the  3 separate mandibles that were found. Therefore, we can know a more accurate idea of the ages of the victims by depending on the maturation of crowns and also transparency of roots.

Age 
Finding out the younger victim's age is straightforward enough via tooth eruption studies. The presence of deciduous teeth, also known as milk teeth, suggests the victim is an infant or child, as these teeth tend to be lost by around age 12. Similarly, the lack of wisdom teeth indicates the victim is under the age of 21. The eruption and loss of specific teeth tend to occur at particular ages. By studying these teeth, it is often possible to pinpoint the age of the victim quite accurately.

Based on the tooth eruption dates, it would also be safe to assume that one of the victims which have all 3 posterior back teeth would be at around 17 years old or older as the 3rd molar which is present would only erupt around the age of 16-17 at the earliest.

Comparative Dental Identification 
We would then attempt a comparative dental identification. The antemortem records of the shortlisted missing people, which are likely to be written notes, study casts and radiograph are compiled. Then, I would come up with a postmortem record with charting and written descriptions of dental structures and radiographs. Subsequently. each tooth structure will be compared in turn and a conclusion would be established. The possible results could be:

1) Positive Identification: Sufficient similarities between antemortem and postmortem records, and no unexplainable discrepancies, indicating that both records belong to the same individual.
2) Possible identification: The antemortem and postmortem have consistent features, but not possible to establish identity positively.
3) Insufficient evidence: The information is not enough to form a basis for conclusion.
4) Exclusion: Antemortem and postmortem details are not matched. Unexplainable discrepancies.

The skull is a very valuable piece of evidence as it reveals a lot about the victim. To find out about the victim's actual age before his/her demise, we would examine the skull and make a comparative analysis using the cranial sutures in the adult skeleton. Normally epiphyseal fusion and sutures of other body parts except the skull is preferable. To further improve the confidence level of the result, we would try to extract information based on the endocranial sutures (inside the skull) as they are more reliable as an aging method than it is for ectocranial suture analysis. To put it simply, the human skull is composed of numerous smaller bone segments, their division giving the skull flexibility. As the individuals age, these segments fuse together by ossification. It is the extent of this fusion which will lead us to the age. For this method to work, the adult victim must be under approximately 30 years old, after which ossification of the human skull is usually complete.

In the advent that the victim is an elderly individual, where suture analysis will not yield results, we shall resort to looking out for worn teeth, signs of bone degeneration, arthritis, osteoporosis (increased bone porosity), and similar diseases as these indicate old age. However the level of wear of teeth can be influenced by diet and cultural practices, so this should be taken into consideration. On the other hand, if dentures or other false teeth are found in or near the remains, this is a further sign of an elderly victim. However, such means are unreliable and a precautionary step in the form of osteon counting by microscopy will be taken. Osteons are minute tunnels within the bone housing nerves and nutrient-providing blood vessels. In general, the more osteons present in the bone, the older the victim.


Sex 
The next property that we would investigate is the sex of the victims. Though they appear fairly similar, female and male skulls do possess some distinctly different features, as aforementioned in part 1. The most straightforward way to determine the victim's sex is thus the examination of such differences.

	Male	Female
General size	Large	Small
Architecture	Rugged	Smooth
Supraorbital margin	Rounded	Sharp
Mastoid process	Large	Small
Occipital bone	Muscle lines and protuberance marked	Muscle lines not marked
Glabella	Bony	Flat
Gonial Angle	Squared	Wide angle
Palate	Larger, broader, tends to be U-shaped	Small, tends to be a parabola
Occipital condyles	Large	Small

The gender of the 2 victims in which only the mandibles have been discovered can also be determined by examining asspects such as the chin and ramus as explained before in part 1.


Ethnic 
Our next priority would be earmarking the victims’ ethnic origins. This information is extremely vital as the search list would be narrowed down considerably. There are a number of differences in the structure and appearance of bones between individuals of different races that can be observed and used in the establishment of a victim’s ethnic origin. The majority of these differences are based in the skull. 

A Caucasian victim will generally display a narrower face and high-bridged nasal bone. The upper incisors will often have a flat lingual surface (surface closest to the tongue). The chin will often be more prominent and the cheekbones fairly flat.
A Negroid skull will often exhibit a broader nose bridge with wider nasal openings and subnasal grooves. The skull will often hold outward-sloping jaws, with the lingual surface of the upper incisors being flat.
The skull of a Mongoloid victim will be broader around the face, with squarer, forward-sloping, wing-like cheekbones and a lower nose bridge. Unlike Caucasians and Negroids, the upper incisors are likely to be shovel-shaped and the skull flatter.


Forensic Facial Reconstruction 
By using forensic facial reconstruction, we can also recreate the imaginary face of an individual either into two or three dimensional by using the evidence found.

How would we carry this out?

Initially, the skull is cleaned of any remaining tissue in preparation for the reconstruction. A number of round, rubber markers are placed at specific points on the skull. These landmarks are used to indicate the depth of flesh in these locations, their depth being dependent on the likes of sex, age, race, and the all of which are investigated earlier. Then, strips of clay are attached to these landmarks, with more clay applied in between to act as the ‘flesh’ of the face. Facial muscles are laid over the flesh, their structures and sizes based on the shape and size of particular facial bones. External features are then added, such as eyes, ears and a nose. Finally, the skin is coloured and an appropriate hair colour and style selected, with reference to the victim's ethnic origin. Many of these external features are the most distinguishing points of a person’s face, but are unfortunately difficult or impossible to predict.

The result is essentially a clay model depicting the likely appearance of the unidentified individual. Though this may not be used as a sole identifier, the image may be distributed among the public, or cross-checked with the possible identity's list so that only a few shortlisted candidates remain, which would expedite the investigation process and conserve time.

Hence, for at least the adult victim, we should be able to get a clear picture of his/her appearance using this technique since there is both a skull and a jaw that can be used for the process whereas for the other victims, there may not be sufficient information for this technique.


Getting the identification of the victims will give us a headstart in the investigation. Alongside the cause of death, which we will discuss about shortly,  it helps us to reconstruct the final stage of the victim's life. Forensic entomology is implausible in this case as all the evidences are bony parts. The conventional methods of measuring body temperature, looking for rigor mortis and the colour of the skin are not practical as well.

We would then shift our focus to determining the time of death of the victims.

Time of death 
Radiocarbon dating
The first way we would attempt to obtain an accurate estimate of the time of death would be via radiocarbon dating. This is done by determining the radiocarbon content in tooth enamel by using radiocarbon-14 dating. Radiocarbon dating works on the principle that the radioisotope carbon -14 is taken up by organisms during life. Accumulation of carbon-14 by the body will stop upon death, and will decay at a fixed radioactive decay rate. Therefore, by knowing the carbon-14 content in the deceased and through calculations, the age and year of death of the victim can be estimated.

We could then consider analysing soil samples at the crime scene from which the remains were found

Soil samples 
This is because as bodies decompose, they leak certain chemical compounds into the ground. Since the profiles of these compounds vary as time passes, analyzing them can reveal how long a body has been dead and pinpoint how long a body has been lying in a particular place. One of the technique tracks the ratios of seven inorganic compounds, such as sodium and calcium, which leach into the soil from the bones. If a body is too badly decomposed for those techniques, scientists rely mostly on bones. If the surrounding soil does not contain the telltale chemicals released as a body decays, the body was probably placed there recently. Soil samples containing those chemicals help experts guess how long it has been since the person died. This number can be the key to whether an alibi flies or flops in a murder trial.

However, we would have to consider a lot of other conditions that can alter how a body decomposes during this process. This includes all the biological and non-biological processes that contribute to the decomposition, skeletonization, and depositional changes associated with a set of remains. Biological factors include human agents, animals, plants, insects, and invertebrates. Carnivore scavenging of fresh remains and rodent gnawing of dried remains are common. Plant roots can etch into bone surfaces while insects and worms can move remains during tunnelling and nest-building. Low soil pH, wind, water, and sand are all capable of abrading bone surfaces. Repeated freeze and thaw cycles can reduce a bone to fragments while intense heat and sun can cause the surface of bones to crack and peel away. Knowledge of such taphonomic processes is instrumental to estimate the length of time a body has been buried or exposed, or determine whether a set of remains has been moved.

The next aspect of our investigation would the cause of death

Cause of death 
Dr. Rudi mentioned that there might be ‘Blunt force on the back of the head’. However, it is not inclusive as there were too many pieces of evidences yet to be put together at that point. Hence by closely examining the size and shape of the injury of the skull, we can identify the weapon used and find evidences of the weapon in the vicinity.

With no flesh remaining, it is our duty to seek out clues as to how the victim died and what injuries they received. Whereas in many cases it may be impossible to tell, some injuries do leave tell-tale signs on the bones.

Murder weapon 
Sharp blades such as knives, if plunged into the body deeply enough, will often leave nicks and grooves on the surfaces of any bones they come into contact with. When the blade meets the solid structure of the bone, it is also possible that fragments of the blade are broken and left behind with the remains, ideal for later comparison to weapons. Such discovered fragments may be matched directly to the weapon used, or they may at least give some indication as to the type of weapon. 
A bullet may leave numerous markings on bones. If the bullet passed straight through bone, distinct holes could be observed. Such a projectile also has the potential to completely shatter a bone, or at least leave noticeable scratches across the surface. It is possible that bullets may have been left behind in the remains, stuck in one of the bones or caught up in leftover tissues.

Forceful blows to the skull will often leave obvious fractures or even holes, the study of which can even aid in the identification of the murder weapon, more so if a narrower, sharper weapon was used. The use of a larger, blunt object produces wounds described as blunt force trauma. Blunt force trauma may leave a pattern of radiating fractures around the point of impact, the extent of these fractures indicating the force of the blow. If there are multiple blows to the skull, any radiating fracture lines from following strikes will stop at existing fracture lines. The study of these can determine the order in which the injuries were received. The skull itself is composed of a spongy layer of bone sandwiched between two harder bone layers. The inner side of the skull is cushioned by the outer and middle layers, thus is can be assumed that great force was employed if all three layers are shattered. 

Previous injuries 

It is possible that not all injuries visible were received during the fatal incident, but these older wounds should still be examined closely. Fractures and similar injuries showing signs of healing may not be relevant to the current investigation, however they could be signs of previous assault, so should be taken into account nonetheless. Even fractures suffered a long time ago will be visible, potentially signifying injuries obtained during childhood. Periods of illness or malnutrition may also leave behind signs on the bones. During these periods, bone formation occurs at a slower rate between the end of the bone and its shaft. Once normal growth commences, a slight line is left behind in the bone, known as a Harris line, which can be visualised using x-ray techniques. By studying charts of known bone growth, it is even possible to establish roughly at what age this period occurred. 

Pattern of injury
In addition to the injuries themselves, the patterns of injuries present on a body can be very important to the case. The direction of projectile wounds can also be used to support or refute a suspect's story. We would carefully record all traumata according to type, location, and number to reconstruct the overall picture of what happened to the victims at the time of their death.


The ultimate outcome 
Once this is complete, we would have a rough estimation of the victims identities,age,gender,ethnic origins, the estimated time of death and the cause of death.

Using this information , we would be able to greatly decrease the scope of the suspected victims on the missing peoples list hence greatly increasing our chances of confirming their identities. Once the identities are confirmed, we would be able to obtain information on their occupations, lifestyles,families,friends, etc and obtain a clear picture of their final days before the incident, thus trying to relate them to the scene of the crime.
We will also be able to get a clear idea on how the incident took place, confirm the scene of the crime and subsequently determine how  the possible assailants/suspects may be related to the incident.

Well that not only marks the end of question 5 and week 2, but also the half way mark of the assignment!

Stay tuned for more from us next week!

Introduction to the Men-dibles

A Long long time ago, in a land far far away, 7 men from different walks of life who knew nothing about Forensic Dentistry met in an intersection known as IMU. We were brought together to complete a specific set of tasks, mainly ……….

BLOGGING.

We were given an opportunity by Dr. Ahsan to dwelve into this mysterious field of Forensic Dentistry. We did not see this as a chore but as a challenge as young aspiring dentists.

The memoirs of your not so average dentist

Lets get on to business then, starting off with question 1, however before we begin, here’s a disclaimer:  

It’s kind of a long post, so..

What is Forensic Dentistry?

Forensic dentistry or Forensic Odontology is the application of dental knowledge to those criminal and civil laws that are enforced by police agencies in a criminal justice system. Forensic dentists are involved in assisting investigative agencies to identify recovered human remains in addition to the identification of whole or fragmented bodies; forensic dentists may also be asked to assist in determining age, race, occupation, previous dental history and socioeconomic status of unidentified human beings. Identification is done by the comparison of ante mortem and post mortem dental records and using the unique features visible on dental radiographs

Forensic dentists are responsible for six main areas of practice:

•         Identification of found human remains

•         Identification in mass fatalities

•         Assessment of bite mark injuries

•         Assessment of cases of abuse (child, spousal, elder)

•         Civil cases involving malpractice

•         Age estimation

An example of forensic dentistry used to solve a crime was in January 1978 in United States, a serial killer, Ted Bundy. One of the earliest known examples of forensic dentistry involved Agrippina, the mother of Roman emperor Nero. In 49 B.C. Agrippina ordered the death of her rival Lollia Paulina, who was in competition with her to be the wife of Emperor Claudius. Agrippina demanded to see Lollia Paulina's head as proof of her death, but she wasn't sure that her rival was dead until she noticed Lollia Paulina's distinctive discoloured front teeth.

How Forensic Dentistry plays a role in identifying burnt victims?

-    Basic identification is not so difficult a task for the most part, however, when the victim is burned beyond recognition, more complex methods must be utilized as a means by which to establish positive identification. These methods include, DNA fingerprinting, forensic odontology, and cranial base evaluation. With the incorporation of these methods, it has made identification of a severely burned body possible.

-    A body that has been only partially burned can be identified through DNA fingerprinting. 

-    When the body is burned to such a degree that all that is left is skeletal remains, forensic odontology becomes the primary means of victim identification in Canada. Dental records serve as more than merely an accumulation of one's cavity history; rather, they become the link between an unidentifiable fire victim and one who can be recognized by tooth imprints. However, in order for forensic odontology to be effective, the victim's remains must be handled with extreme care so that critical identifying information is not further damaged or destroyed. "A systematic, conservative approach prevents the loss of valuable dental information before a thorough picture of the individual's dental remains has been adequately documented." The process that revolves around forensic odontology entails compiling a comprehensive dental charting that provides information via oral structures intra-oral photographs and radiographs as a means by which to piece together the puzzle that represents forensic odontology. "Utilizing methods of access to the oral structures that maintain the integrity of the dentition through each stage of the evaluation of charred remains will prevent the loss of potential dental information..." While forensic odontology has been extremely instrumental in identifying myriad burn victims, it is not a flawless method of classification due to the inaccuracies inherent to such a process. In order for Canada's forensic odontologists to positively identify a burn victim, the individual's records must be recovered; this initial step might seem rather uneventful, however, with the decrease in dentist visits over the past decades, obtaining accurate records is becoming more and more difficult. Additionally, dentists are under no obligation to maintain detailed records of their patients, which serves to create a wide margin for charting errors and mis-identification when molars resemble one another or because there may have been an extraction at one point that allowed for another tooth to take its place. "The use of high-resolution digital scanners are helping to remove the personal judgement element in the old methods of forensic odontology."

Additional - Using Cranial Base method.

-    Still another technique for identifying the remains of a burn victim is through cranial base evaluation. The fundamental basis of this particular method involves measuring for specific size in order to determine the race and sex of skeletalized victims. "Determination of race (ancestry) is an important step in the identification of individuals in forensic cases. Race is most commonly assessed using cranial traits." While this method is highly effective, its major drawback - the potential for skeletal shrinkage - is quite significant as well. If the cranial base shrinks from its normal size, which is a distinct possibility in the event of fire, the task of sexing the victim becomes even more difficult due to the potential misrepresentation of proportion. The recent upsurge in the study of human genome science has an association with burn victim identification, inasmuch as findings have indicated that there exist a certain number of short tandem repeat (STR) loci in Quebec's French Canadian population. These loci, which "represent a rich source of highly polymorphic markers in the human genome," have proven effective in relation to forensic identification and biological correlation of Canadians. Research indicates that the six STR loci "are informative genetic markers for identity testing purposes in the French Canadian Caucasian population of Quebec." That Canada's research with regard to forensic science has progressed forward at such an advancing rate clearly denotes a tendency to set precedence when it comes to the future of burn victim identification. "...Forensics in Canada has been in the international forefront since the inception of the first forensic laboratory in North America, in Montreal in 1914...Canadians have made significant contributions to the international scene and their credit is deserved."

How does forensic dentistry play a role in identifying victims with bite marks?

• The first step in analysing the bite is to identify it as human. Animal teeth are very different from humans' teeth, so they leave very different bite-mark patterns
• DNA may have been left in the saliva of the biter
• Each individual bite mark is measured and recorded
• Photographs are taken due to the changing nature of the bites
• Bruising can appear four hours after a bite and disappear after 36 hours * The dentist may have to wait until the lividity stage, or pooling of the blood, clears and details are visible
• Bite marks on deceased victims are cut out from the skin in the morgue and preserved in a compound called formalin, which contains formaldehyde
• Dentists then make a silicone cast of the bite mark

Forensic dentists use several different terms to describe the type of bite mark: 

• Abrasion - a scrape on the skin
• Artifact - when a piece of the body, such as an ear lobe, is removed through biting
• Avulsion - a bite resulting in the removal of skin
• Contusion - a bruise
• Hemorrhage - a profusely bleeding bite
• Incision - a clean, neat wound
• Laceration - a puncture wound

There are different types of impressions that can be left by the teeth as well

• A clear impression means that there was significant pressure
• An obvious bite signifies medium pressure
• A noticeable impression means that the biter used violent pressure to bite down

A forensic dentist can tell a lot about the teeth of the biter based on the bite mark

• If there's a gap in the bite, the biter is probably missing a tooth
• Crooked teeth leave crooked impressions and chipped teeth leave jagged-looking impressions of varying depth
• Braces and partials also leave distinctive impressions

Once investigators have identified a suspect, they obtain a warrant to take a mold of his or her teeth as well as photos of the mouth in various stages of opening and biting

• They compare transparencies of the mold with those of the bite-mark cast
• Photos of both the bite mark and the suspect's teeth are compared to look for similarities 

 

By now you are probably feeling that

We know its been a long post so far, but fear not, as..

Lets continue,

Forensic Dentistry in Identification of murder victims

Forensic dentistry is specifically used when the murder victim is so extensively disfigured that it becomes impossible for an individual to visually identify the victim.

There are several causes to the disfigurement including:

• Burnt victims
• Those who had deceased for a long period of time prior to discovery
• Those who are found in water

Teeth are a repository for unique features and they survive most trauma and postmortem event that can disrupt other body structure. This is because enamel is the strongest structure in the human body. Teeth aren't as unique to a person as a fingerprint, but dental evidence can be instrumental in establishing a person's identity.

• The size of teeth can give clues to a person's approximate age because of how fast teeth grow -- about four micrometers a day.
• Different ethnic groups also tend to have distinctive dental features, such as incisors with concave backs.
• The patterns left on teeth over time due to the wear and tear of a person's eating habits and lifestyle can also provide convincing evidence about a person's identity.
• The teeth itself is a fantastic source of DNA because of its resistant nature towards environment insults such as incineration, mutilation, and decomposition.

Teeth are not cataloged in a central database, like DNA, so forensic dentists use antemortem dental records and postmortem dental records in order to make comparisons.

1. Antemortem records are obtained
2. Postmortem records are produced by careful charting and written descriptions of dental structures and radiographs
3. Comparisons are made between antemortem and postmortem records, examining each tooth and the supporting structures in turn
4. Similarities and discrepencies are noted
5. Conclusions are made

With the help of forensic dentistry, we can definitely narrow down the population pool to which the deceased belongs to, and hopefully correspond to the relevance of the case at hand.

The Women-dibles and the Men-dibles

If you have read EVERYTHING so far, you're probably like

SO before we even begin with Question 2, here's a little trivia..

A tourist in Vienna is going through a graveyard and all of a sudden he hears some music. No one is around, so he starts searching for the source. He finally locates the origin and finds it is coming from a grave with a headstone that reads: Ludwig van Beethoven, 1770-1827. Then he realizes that the music is the Ninth Symphony and it is being played backward! Puzzled, he leaves the graveyard and persuades a friend to return with him. By the time they arrive back at the grave, the music has changed. This time it is the Seventh Symphony, but like the previous piece, it is being played backward. Curious, the men agree to consult a music scholar. When they return with the expert, the Fifth Symphony is playing, again backward. The expert notices that the symphonies are being played in the reverse order in which they were composed, the 9th, then the 7th, then the 5th. By the next day the word has spread and a throng has gathered around the grave. They are all listening to the Second Symphony being played backward. Just then, the graveyard's caretaker ambles up to the group. Someone in the group asks him if he has an explanation for the music.

"Don't you get it?" the caretaker asks incredulously. 

Take a guess before u uncover the answer at the end of the page ;)

On to the question.

First of all, what is a skeleton?

The Skeleton is an excellent material in the living and non living population for genetic, odontologic and forensic investigations. Skeletons vary from male to female and differentiation is usually based on the male features that are typically more pronounced than the female features.

The determination of sex by examination of the skeleton is based upon the appearances of
a)Skull
b)Pelvis
c)Long bones
d)Sternum
e)Scapula, metacarpal bones


However, today we will be focusing on the "SKULL"

So what is a skull?

The skull is a bony structure which serves as the general framework for the head. The skull can be divided into 2 parts: cranium and mandible

So why is a skull important in forensic science ?

Forensic anthropologists are often called upon in situations where remains are badly decomposed and require an expert to determine the age, sex, height, and other traits that will help identify the deceased.

If an intact skull, or other bone, is present, the forensic anthropologist's job is much easier.

1.Age

The skull consists of several plates connected by what are called cranial sutures. These sutures gradually fuse over time, and fuse at different rates. While exact age cannot be determined by the appearance of the cranial sutures alone, an approximation of age can be determined

2.Race

Bone thickness and bone structure, are both used to help determine possible hereditary affiliation. Data has been collected through the years to help determine any structural differences between skulls of people with Asian, African, or European origins respectively

3.Health

Examination of the teeth can yield important information about diet, general health, and tobacco use.

4.Cause of death

Fractures and other traumas must be examined carefully to attempt to distinguish between traumas that are antemortem (before death) perimortem (at or around the time of death), or postmortem. Scavengers, and even the weather, can cause postmortem fractures that may appear to have been caused by perimortem violence. Weather, the chemical components of the area in which the skull was found, and many other factors play a role in how quickly the bone dries; therefore, the forensic anthropologist will take these factors into account when attempting to determine whether a skull injury occurred at the time of death of after

5.Sex ( our main concern for this question)

Firstly, the features of the skull that indicate sex are

1.General appearance


Male    = skull is usually larger, heavier, thicker and more rugged

Female = skull appears smaller, lighter, thinner  and more gracile

2.Supra orbital ridges


Supra orbital ridge is more marked in males

3.Orbits


Male   = Squarish with roundish margins

Female= Roundish with sharp margins

4.Glabella

Male   = Well developed

Female= ill developed

5.Zygomatic arches

Males    = Zygomatic arch is more pronounced, wider and tends to extend posteriorly beyond the 
               EAM

Females = Zygomatic arch is less pronounced,narrower and tends to not extend posteriorly beyond 
               the external auditory meatus (EAM)

6.Mastoid processes

Male    = Larger and more blunt

Female = Smaller and more pointed

7.External occipital protuberance


Inion may be more prominent in males, sometimes to point of appearing hook-shaped

8.Mandible (Chin and Ramus)

Chin

Male (left)       =  Mandible tends to have a square shape

Female (right)  = Mandible tends to have a pointed chin

Ramus

Male    = Mandible is wider, larger and closer to a right angle than the female

Female = The ramus is an obtuse angle to the lower jaw bone

9. Palate


Male    = Larger, wider and broader

Female = Smaller and narrower

10.Forehead

Male     =The frontal bone of males is slightly sloping or receding

Female  =The frontal bone tends to be more rounded

In general, These are the differences

Cranium Feature	Male	Female
Frontal Bone (forehead)	Lower/sloping	More vertical and rounded
Temporal Ridge	Large	Small
Bony superciliary arches (browridges)	Prominent	Absent/slight
Mastoid process	Large	Small (generally)
Supraorbital margin (ridge above eye)	Rounded	Sharp
External occipital protuberance (protrusion on lower back of the cranium)	Generally present	Generally absent
Nuchal crest (low ridge along the base of the cranium)	Rugged, well defined	Smoother, even absent
Nuchal line	Rugged and sharp	Absent
Zygomatic process (cheek bones)	Extends past external auditory meatus	Does not extend past (generally)
Mandible	Larger and more robust (thicker)	Smaller and lighter
Symphysis and mental eminence of mandible (chin)	Square	Rounded (generally) or pointed
Ramus of mandible	Straight	Slanting
Mandible gonion and gonion angle (back corner of jaw bone)	Flaring & sharply angled	Less so
Sinuses (air ways)	Larger	Smaller
Teeth	Larger	Smaller
Cranium	Deeper and larger by about 10%	Smaller
Total skull	Rougher, heavier	Smoother and more rounded

 This is an introductory video giving basic trait differences between male and female skulls.



NOW, the answer for the initial query is....

He's decomposing...