Forensic Anthropologist

14 05 2010

Anthropology is the science of human zoology, evolution, and ecology according to the dictionary. Forensic Anthropologists apply the science of physical anthropology to the legal process. They identify skeletal human remains

Anthropologists…

  • Search and recover human remains
  • Estimate the time since death
  • Does osteological analyses to establish the biological profile of the victim
  • Does pathology assessment from human skeletal remains to figure about if the victim had a trauma or a disease

(From www.all-about-forensic-science.com)

Forensic anthropologists are called in for death investigation. In solving the crime, anthropologists’ main goal is to create a biological profile. They do so by examining human remains. They use their expertise in doing human skeletal anatomy to do their part of the investigation. The profile, which serves as a critical evidence, is given to the police. They also calculate the recency of the remains that will be used to see how they fit into the general context of the crime scene. They are sometimes called to distinguish the human remains from non-human remains. It is told by people who experienced it that the smell and the sight of decomposing human is just unbearable.

The skull is the most diagnostic area for building a biological profile. The biological profile includes age, sex, ancestor, height, and whether the deceases had a disease. When creating a biological profile of a human being, first you determine the sex of the victim. You will have to examine the brow ridges to figure out the sex. Females’ tend to be less robust than males’. You can also look at the rear of the skull. There is this bun looking region there. This is also more robust in males. The cranial suchers, the top of the skull, can help determine the age of the deceased. The older the person gets, the cranial suchers become diffused together more tightly. The teeth can be also used. If one has the third molar, it indicates that that person was an adult. DNA is also preserved in teeth better than in bones. However, when dealing with forensics, hair, tissue, skin, and other parts of the body will be more useful in DNA analysis.

This video explains what I have explained above about skeleton analysis in depth.

Forensic anthropologists do not work full time, because they mostly work with colleges and provide consultation. Almost all of them are professors of biological or physical anthropology with Ph.Ds. If you are considering to become a forensic anthropologist, you should look at this aspect of the job and reconsider.

An anthropologist integrate many other subjects to do their job. They need to know osteology, which includes skeletal anatomy and biology, in details. They also need to know bits of biology, archaeology, genetics, and cultural aspects. To become a forensic anthropologist, Undergrad majors in Human Biology or Physical Anthropology are recommended. Physical Anthropology is preferred. You will need to cover hominid physiology, anatomy, and other anthropology classes. Then, obtaining masters degree is your next step. Ph.D specializing in forensic anthropology is preferred. Becoming a forensic anthropologist is a long tiring career. One has to withstand the smell and the pain of seeing a decomposing human being. In the United States, there are only about 150 active forensic anthropologists. However, it is rewarding.

The forensic anthropologists earn $40,000 to $50,000 if they have MA/MS degree. If they have a Ph.D, they earn about $60,000 to $85,000. However, it mostly depends on your skills, experience, and responsibility, like all other forensic jobs. You have to constantly work hard to get this job.





Brave New World and Today’s World

28 04 2010

I was given an assignment by my English teacher, Mr. Stephens, to make a connection between one of the texts we have read this year and the world. This year, we have read Beowulf, Grendel, Macbeth, Strange Case of Dr. Jekyll and Mr. Hyde, and Dracula. We are currently reading Brave New World by Aldous Huxley.

I chose to talk about the connection between Brave New World and the world. Brave New World is prophetic satire about our world, which turns in to the “World State” where all people are conditioned to think the way that will not go against the World State’s motto, “Community, Identity, Stability.” In the World State, people are born through a high-tech reproductive system. Cloning is common in the World State. They use Bokanovsky’s process to create identical twins to maintain stability in the world. When being made, humans are divided into five different castes: Alpha, Beta, Gamma, Delta, and Epsilon. People are all conditioned to be happy with their state, regardless of their social caste. This is done by something called hypnopaedia, or sleep learning, which unconsciously makes some things become embedded in people’s mind. If they really become unhappy, there is always soma present for them to take. Brave New World shows how much the definition of “happiness” can be deteriorated.

Brave New World is supposed to be the ideal world. However, it seems more like a dystopia where only forced happiness exists.

In today’s world, unlike the World State, we have more freedom of thinking and more uniqueness. However, we cannot say that we are completely different from the World State. We are indeed being conditioned also by media, and we are indeed trying to fit in the society. What is our definition of happiness? Being better than other people? That is not the meaning of true happiness, but media is depicting the definition of happiness as “success” or “being the best.” The media is not a reliable guide. Yet, it is still the greatest influence to human beings. We get judged and divided into groups depending on our level of knowledge and our level of success. Are we not divided into castes? I think we are.

The only difference that exists between the two worlds is the love. Emotions exist in this world unlike the World State. We cannot say that Huxley’s prediction is not so realistic, because if we really think about it, we are really a step away from becoming the World State.





Step by Step

19 04 2010

I know that I have explained how investigators investigate a crime, but I wanted to walk you through the investigation step by step.

Prior to the investigation, you have to make sure you got the agreement and access to search all property and everywhere. A warrant is optional. One needs to get an warrant if he/she cannot get a suspect to cooperate.

  1. The investigation starts by observing the crime scene.
    Field kit is something that you take when you go out to investigate the crime scene. It contains impression materials, tweezers, swabs,  luminol and many other things that are needed to collect evidences.
  2. Collecting evidences
    A crime is solved by sewing the pieces of evidences together. There are evidences everywhere at the crime scene. If you just pay attention and investigate thoroughly, you will be able to find some evidences that will help you with your investigation.

    - Food as evidence
    Food can serve as an important evidence that can help us figure out the cause of death. We can analyze whether the food contains toxin or not to figure out if the food was used to sedate or poison the deceased. The food will be taken to the toxicology station in the lab to be analyzed.
    - A notepad as an evidence
    A notepad can serve as an evidence too. There might be something crucial written, such as the victim’s schedule, or there might be indented writing that has to be taken to the lab and observed under the light table.
    - Hair (or other things that can serve as DNA) as evidence
    DNA Analysis can be done to analyze the DNA left at the crime scene. It can later be compared with the suspects’ DNAs. Not only hair, but also things such as saliva, skin cell, and bodily fluid can be used for DNA analysis.
    - Corpse as evidence
    The corpse of the deceased is certainly a cruicial evidence. It can be used to figure out the cause of death and the manner of death by doing a medical examination. Specifically, pathologists will carry out autopsies. By doing an autopsy, the time of death can be estimated. The body temperature at the scene tells the recency of the death. We must look for swelling, contusions (bruises), lacerations (cuts), and bone fractures. A puncture wound shows that the victim was possibly injected with a drug or a chemical that led him/her to death. A bite mark serves as a wonderful evidence that can possibly lead to the identification of the culprit. It can be used to compare with the impression of the suspects, and the saliva on the bite mark can also be used to compare the DNA with the suspects.
    - People as evidences
    If someone hated the victim, that person is a suspect. If someone knew the victim well, that person is also a suspect. People’s DNA can be collected for DNA analysis to see if that person is who left their trace at the crime scene. Teeth impression can be collected to compare the teeth structure with a bite mark, if there is one. Comparison microscope will be used to complete such tasks.
  3. Testing the evidences
    After you collect all the evidences you want, you will go to the lab, or the morgue for the corpse, to find useful clues from the evidences.

    - Fingerprint Station
    The Fingerprint Station has the powders and chemicals necessary for processing any fingerprints. The computer has a database called CODIS with DNA information of previous suspects.
    - Toxicology Station
    The toxicology station is valuable when detecting the presence of drugs and other chemicals in substances such as blood, urine, and other bodily fluids.
    - DNA Station
    The DNA station processes evidences with DNA. They are things such as hair, blood, saliva, and sweat. CODIS is used here also.
    - Light Table
    The light table is useful when analyzing and comparing pieces of evidence in detail
    - Comparison Microscope
    The comparison microscope is used when comparing two objects. It can be used when comparing teeth impressions or fingerprints.
  4. Step 2 and 3 are repeated constantly until sufficient evidences  and clues are found.
  5. If clues are found adequate enough to surely hypothesize the culprit and how the crime occurred, the culprit is called upon and questioned.
  6. After the suspect confesses his/her crime, they are sent to the court to be sentenced.
  7. CASE CLOSED :)

As I wrote down the process of investigation step by step, I, once again, realized how important evidences are. The evidences start the investigation and end the investigation. I think a crime scene investigation is all about  how well you find the evidence, how well you sum them up together, and how apply the evidences to solve the crime. To become a crime scene investigator, I think the most important skill to have is finding and using evidences efficiently.





Hair Analysis

19 04 2010

Q

An intentional murder has occurred. The victim was stabbed several times. The culprit has not yet been discovered. There are three suspects that the investigators are suspicious of. They were confused between the three. Then, a strand of hair was discovered on the ground. They immediately got the warrant to get all suspects’ hair. What should one do as a forensic scientist?

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A

One should carry out a comparative analysis using the comparison microscope to compare the unknown hair and the suspects’ hairs.

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Hair is the outgrowth of filamentous cells containing keratins from the follicles. A strand of hair can tell us a lot about the identity of the culprit. This is the structure of a strand of hair.

What distinguishes human hair from other species are the cuticle and medulla.

Two light sources can be used to examine a strand of hair: direct and oblique. Direct lighting is lighting from underneath. It shows the inner structures of the hair. Oblique lighting is lighting from the side. It highlights the cuticle of the hair.

Hair can have three scale patterns.

  1. Coronal
  2. Spinous
  3. Imbricate

1. Coronal
Coronal pattern has scales that look like stacked crowns or paper cups. An example is a bat’s hair.

2. Spinous
Spinous scale pattern has petal-shaped scales, protruding from the hair surface. The example of a spinous pattern is rabbit hair.

3. Imbricate
The scales of imbricate pattern are flattened to lie closer. Humans and dogs have this pattern.

There are three types of medulla.

  1. Continous
  2. Interrupted
  3. Fragmented/Absent

1. Continous
A continous medulla is the medulla formed in the center of the hair as a solid line. An example is the dog’s hair.

2. Interrupted
The medulla is seen as individual cells, as if it is fragmented. The pattern can be regular or irregular. The rabbits have this type of medulla.

3. Fragmented/Absent
There is almost no medulla in the hair. This is a characteristic of a human hair.

The follicular tag tells whether there is a nuclear DNA or not.  The follicular tag surrounds the root, which is the site of hair growth. It supplies the hair with nutrients. When hair is pulled out, the follicular tag is sometimes removed. Even if there is none, we can still test for mtDNA, or mitochondial DNA.





Toxicology

5 04 2010

Q

There was a car accident. A car crashed into another car. The man who crashed into another car was a good man. He was a dilligent worker and a good father. The investigators want to know why the man did such thing. They are wondering if the man was drunk or on drugs. What should they do to find out if the man was drunk or on drugs?

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A

They should ask the toxicologist to analyze by doing head gas chromatography, elisa test, and gas chromatograph/mass spectrometer. Doing head gas chromatography will reveal the presence of alcohol, and elisa test and GC/MS will reveal the presence and the type of drugs.

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In the 16th century, Paracelsus realized that anything can kill a human if it is taken excessively. But forensic toxicology wasn’t invented until the 1840s. A chemist named Mathieu Orlifa proved in court that Marie LaFarge poisoned her husband with arsenic.

Toxicology is science concerned with nature, effects, and detection of poisons.Forensic toxicologists test human fluids and tissues to determine the presence of drugs and other chemical substances.

In order to carry out the test, toxicologists draw out 3 types of bodily fluids

  1. 2mL of vitreous humor
  2. 30mL of blood
  3. 30mL of urine

1. 2mL of virtreous humor

Virtreous humor is the clear fluid inside the eye that give the eye its shape. It is inside your eye balls! Virteous humor is used as a confirmation to confirm the results from the blood and urine, because if a drug is present in any of these fluids, it will be present in all three. The vitreous humor is collected using a syringe. The toxicologist pokes the syringe through the eye ball and extracts the fluid inside. I won’t upload a video, because it is a quite disgusting process to see :(

2. 30mL of blood

Blood transports oxygen, nutrients, and other chemicals throughout a person’s body. Hemoglobin is a well known protein in blood that transports oxygen. Most chemicals in the body will appear in a person’s blood stream. Once the drug enters the blood stream, it will spread all throughout the body.

3. 30mL of urine

Urine is the main way toxins and other chemicals exit the body. The toxicologist collects the urine postmortem from the bladder, again, using a syringe.

So why are three fluids examined? It is because looking at multiple fluids helps prevent error and contamination. If a drug is present in one part of the body, it should also be in others.

These are the sccening tests driven to determine the presence of alcohol/drugs.

  1. Headspace Gas Chromatography
  2. Elisa Test
  3. Gas Chromatograph/Mass Spectrometer

1. Headspace gas chromatography

Headspace gas chromatography is used to refer to the area between the sample and the top of the vial. The alcohol in the sample will evaporate into the headspace, where it can be analyzed.

2. Elisa Test

Elisa test is used to detect drugs in the sample. It can detect the presence of drugs, but it cannot definitely identify individual chemicals. All samples and controls are replicated twice the make sure no mistakes are made. The samples change color when a drug is detected. Positive and negative controls are used to ensure that the test is working correctly. The positive control purposefully have drugs, and the negative control doesn’t.

3. Gas chromatograph/Mass spectrometer

To find out the exact drug, gas chromatoraph/mass spectrometer, or GC/MS is used. It is only used if something shows up in the screening tests, because this is a very expensive test :(. GC/MS separates the chemicals in a specimen and identifies each one. It takes up to 20 minutes for the processing to complete. The chemicals in the sample separate from each other based on their properties. Then, the chemical gets a positive change in the ion source, and breaks into fragments. The analyzer sorts the fragments, again, by similar properties. The detector calculates the number of chemical fragments of each type. A graph is generated for each chemical. The graph is called mass spectrum. The chemicals broken into fragments are indicated as the peaks on the graph. Every chemical has its own unique pattern. The presence of drug is found by comparing the graph to other graphs of samples with different types of drug intake.





Medical Examination

28 03 2010

Q

A teenager was found dead one day. The parents have no idea why their child is dead. They want to find out the cause of death and the manner of death. What should they do?

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A

They should request medical examination. External and internal autopsies will be done to figure out the cause and the manner of death.

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Medical Examination is the first thing done when the corpse arrives in the laboratory. The first thing the medical examiner does is an external autopsy; they look for clues on the outside of the body. This is done, because in most cases, what can be found on the outside can be more helpful than what can be found on the inside. Then, internal autopsy is done. The examiner looks at the internal organs to find out if he/she had a disease or damage. Many years of training in medical school must be done to become a forensic pathologist, as I said on a post that I wrote before.

First, before you start any autopsy process, you need to put on protective materials, such as gloves, eye protection, surgical clothes, etc.

Autopsy is a very complicated process, that requires a good stomach. You will be able to find a good amount of disgusting pictures if you type “forensic autopsy” on google! The autopsy always begins with a Y-incision. Next, you will remove the rib cage and expose the inner organs. You will use the rib cutter to do so. Then, you will extract some blood to use as samples for the toxicology lab.  You will poke the syringe through the heart for extraction. You will then use a technique called Rokitansky’s technique. All organs will be removed together and further dissected outside the body. Scalpel will be used to carry out this process. Then, you will need to observe the brain for signs of trauma. You will first have to expose the skull. Stryker saw will be used. Now, all necessary organs are removed. They can be now studied individually in more detail. You will weigh all organs and cut them open. Observing the organs will lead you to figure out what the cause of death is. After you figure out the cause of death, you will also have to figure out the manner of death. Manner of death is what describes how the cause of death occurred.

There are five choices

  1. Natural
  2. Homicide
  3. Suicide
  4. Accidental
  5. Undetermined

1. Natural

Natural death is sudden or unexpected death cause by disease, usually by heart disease, brain system disorder, and nervous system disorders. It can occur at any age. It is seen in 38% of cases

2. Homicide

It is death caused by another person, intentionally or accidentally. If it was accidental, it is not considered a murder. It is determined by the court. It is seen in 9% of cases.

3. Suicide

Suicide is self-caused death. Usually, suicide committers have psychological problems. It is seen in 9% of cases.

4. Accidental

Accidental death is the most common manner of death. It is used if death was unintentional or unavoidable. It is seen in 40% of cases.

5. Undetermined

Undetermined deaths are deaths that do not have certain circumstances surrounding. This is usually temporary classification until the investigation is complete. It is see in 4% of cases as their final decision.

Even before medical examination, the body can tell us many things about when someone died.

  1. Algor Mortis
  2. Rigor Mortis
  3. Livor Mortis

1. Algor Mortis

Algor mortis is the body temperature. After death, the body cools down at a certain rate until it reaches the surrounding temperature. We insert the thermometer into the liver to accurately measure the internal body temperature.

2. Rigor Mortis

Rigor mortis is the stiffening of the muscles. As time passes, the body will become stiff. Later, It will become so stiff that it won’t be able to be moved

3. Livor Mortis

Livor mortis is the discoloration of the body. Lower areas will turn dark blue or purple, because that is where the blood settles.





Firearms

25 03 2010

Q

An innocent citizen has been shot while he was on a walk. Two bullets have been shot towards him. The investigators gained the bullets that were pulled out of his body after death. The citizen is badly hurt, but has a very poor family. He has this weird insurance where he needs to find the shooter in order to get the money. How are the investigators supposed to find the criminal for this case?

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A

Firearm examiners can match a bullet to a specific gun. The bullets can be given to them to study.

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Firearm means portable gun. Firearm examiners can match a bullet to a specific gun by looking at the shape of the bullet that has been shot.

This gun is semiautomatic hand gun. It fires a single cartridge.

To shoot…

1.Trigger has to be pulled

2. The hammer is triggered to hit the firing point

3. The firing pin hits cartridge, releasing the bullet.

This is a picture of the cartridge and its parts.

There are a few characteristics of bullets that can be used to distinguish them. There are class characteristics, specific for a certain brand or type of firearm, and individual characteristics, specific for an individual fire.

Class characteristics

  1. Conventional rifling
  2. Polygonal rifling

1. Conventional rifling

Conventional rifling is a traditional rifling technique that makes deep, easily visible grooves on the surface of the bullet.

2.Polygonal rifling

Polygonal rifling is a technique that leaves smooth rifling impressions, that can be really har

Individual characteristics

  1. Rifling number
  2. Rifling direction
  3. Striations

1. Rifling number

Rifling number is the number of grooves in the rifled barrel. The rifling number can be determined by rotating the bullet and counting the number of the grooves left on the surface.

2. Rifling direction

Rifling grooves are spiral either to left or right, or right or left, making the spin clockwise or counterclockwise int he air when the bullet is floating in the air. The direction of rifiling is ere

3. Striations

Striation are microscopic scretches ont eh surface inside the rifling impressions. No two firearms will produce exactly

* Rifling impression

Rifling impressions are impressions left on the surface of a bullet after it has been fired from a firearm with a rifled barrel.








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