Introduction to Forensic Anthropology.docx

**Introduction to Forensic Anthropology** **Lecture 1 -- What is Anthropology** **Anthropology**: the study of the biological & cultural aspects of all humans in all places and all times. 1. Across space: all over the earth 2. Across time: from today to 6 million years ago 3. Biological pers...

**Introduction to Forensic Anthropology** **Lecture 1 -- What is Anthropology** **Anthropology**: the study of the biological & cultural aspects of all humans in all places and all times. 1. Across space: all over the earth 2. Across time: from today to 6 million years ago 3. Biological perspective: 4. Cultural perspective: the main way humans adapt to their environment **Sub-divisions of anthropology** - Anthropology is so broad that it is divided into different topics and disciplines. There are two major topics in anthropology: cultural anthropology and biological anthropology. Each of them is further divided into specialized disciplines. **Cultural Anthropology** - Culture is the main way humans adapt to the environment. All humans have culture, but since human groups have colonized the entire planet, they have adapted to different environments and therefore created different cultures. - Religion - Home construction - Child rearing - Tools - Clothing - Music - Food preferences - Language **Linguistic Anthropology** - Linguistic anthropology is a branch of anthropology that studied the role of language in the social lives of individuals and communities - Linguistic anthropology explores how language shapes communication. Language plays a huge role in social identity, group membership, and establishing cultural beliefs and ideologies. **Archeology**: the study of material remains (mainly artefacts), usually from the past, to describe and explain the daily life and customs of ancient people. Archeology also seeks to explain how cultures change through time **Ethnography**: the systematic description of a particular based on firsthand observation. - **Fieldwork**: practical work conducted by a researcher in the natural environment, rather than in a laboratory or office. - **Participant Observation**: refers to the technique of learning a people's culture through direct participation in their everyday life over extended period of time. **Ethnology**: the study of the similarities and differences among recent cultures. **Biological or Physical Anthropology** - The systematic study of humans as biological organisms - Usually, biological anthropology revolves around **two major categories** of questions it seeks to answer. - F**irst Category of Questions**: what are humans from a biological perspective? That is, how are we related to other creatures? Who are our closest living relatives? What makes us similar to other living creatures? How are we unique? - **Primatology**: the study of living and fossilized primates. It is also the main discipline addressing these questions - **Second Category of Questions**: it is related to our origin. Where do we comes from? Who preceded us? How have we evolved through time. - **Paleoanthropology**: the study of the emergence of humans and their later physical evolutions. It is the discipline that seeks to answer such questions. - Fossilized human remains represent the main evidence used by paleoanthropologists to address the origin of humans - The remains or impressions of a prehistoric plan or animal embedded in the rock and preserved in petrified form **Forensic Anthropology**: the study of human skeletal remains for legal purposes **Lecture 2 -- Introduction to Forensic and History** **Forensic Anthropology: An Introduction** - **Time frame and forensic significance** - The time frame set for a body to be forensically significant is 50 years - It is set at 50 years because the family, potential witnesses and possible offender is likely dead. - **Who are the missing?** - The missing are usually victims of homicide, suicidal individuals, - **The forensic community** - **Medical Examiners** - They are the ones who declare someone dead and issue a death certificate - **Forensic Pathologists** - They conduct autopsies to determine cause of death - **Forensic odontologists** - Identify victim by teeth if possible - **Forensic Anthropologists** - They work with skeletal remains and bodies that have been deformed (burnt) - **Ballistics specialists** - They determine the murder weapon (gun) by examining the wound on the victim's body - **Forensic entomology** - They determine time since death of the victim based of the cycle of insects that collect and multiply on the body - **Forensic Botany** - The study of plants to determine time of death of a victim, a body decomposes completely in the first year leaving a patch with no vegetation, but it regrows the second year. You can also determine the original crime scene from the plants that maybe on the body but not the surroundings it was found in. - **Forensic Psychology** - Look at the pattern of crime, objects used, clues left to create a profile for the offender. - **The multiple roles of forensic anthropologist**s - **Mass disaster (natural or caused by humans)** - **Natural Disasters (not forensically significant**): They determine identities of the dead to return them to their families - **Mass Disaster caused by humans:** They identify victims, but it can be forensically significant. - **Warfare crimes (forensically significant)** - When they kill many people and bury them in mass graves to cover up their crimes such as during a genocide. - Once peace has come back to a place of war, they interview possible witnesses to find mass graves and they excavate them. The ultimate goal is to prosecute the murderers. - **Forensic anthropology and history (not forensically significant)** - The history aspect is that there is facts and documents on an individual that can be used to identify a body. - Francisco Pizarro (1475-1541) - This is for only for knowledge, no one will be prosecuted - **Forensic anthropology and archelogy (not forensically significant)** - The Mochica (0-700 C.E) - There are little to no documents on individuals, they research and find cause of deaths in history. - They can find mass murders and deaths in history. **History of Forensic Anthropology** - Thomas Dwight (1843-1911): the father of Forensic Anthropology - The published a paper about identifying the sex of a skeleton based - His findings were never brought to a court of law - **The formative Period (1800s to 1938)** - **The Parkman Murder and the conviction of John Webster (1849)** - Body pieces were found all over the office of John Webster and the body was reassembled by two Harvard biologists - They used the teeth to identify the body of Parkman and was the first use of forensic odontology - **The case of Adolph and Louisa Leutgert (1897)** - Adolph was the owner of a sausage factory who was very rich - Louisa when missing, after searching the factory they found three small bones in a jelly like substance in a tank. - **The Buck Ruxton Case (1938)** - There was a bad smell around the house of Buck Ruxton. His wife and maid had gone missing. - The returned when the smell got worse and found two bodies in a ditch - They put together the bodies and used pictures to carefully put the bodies back together. - **The consolidation period (1939-1971) -- third point is most important** - **Guild to the identification of Human Skeletal Material by Wilton Marion Krogman (1903-1987) in 1939.** - It was addressed to the FBI, so that law enforcement would know that a skeleton can be used to solve murders - It was not wildly read - **The Human Skeleton in Forensic Medicine by Wilton Marion Krogman in 1962.** - It farther spread the word to the wider public - **After WW2, creation of the Central Identification Laboratory in Hawaii by Charles Snow (1947)** - It was created to determine the identity of the bodies of the soldiers after the war. - Most of the questions we use today were developed in this lab. - Thanks to the large number of bodies, they tested many theories to see what methods were accurate - **A similar laboratory was established in Japan during the Korean War (1950-1953) by Dale Stewart** - **Personal identification in Mass disasters (1971)**, by Dale Steward - **Human Osteology: A Laboratory and Field Manual (1971)**, by William Bass - **Modern Period (1971 -- present)** - Creation of a section of physical Anthropology within the American Academy of Forensic Science (1972) - The first time that the term Forensic Anthropology was used. - Creation of the American Board of Forensic Anthropology (1977) - They ensure that the discipline is free from bad science and that all those who have that title are qualified to do such a job. **Lecture 4 -- The Forensic Anthropology Protocol** - **Objectives of a Forensic Anthropology Investigation** - Collection of any physical evidence on a potential crime scene or site - Identification of the victim - Shedding light on the circumstances of death (e.g., cause and manner of death) - Estimation of time of death - **Cause and manner of death** - Cause of death -- medical reason for death - Manner of death: 5 possible manners -- scenario that led to the death - Homicide - Suicide - Accidental - Natural death - Unknown - **The Forensic Anthropology Protocol** - Questions basic to personal identification - Questions regarding the circumstances of death - **The Protocol** - **Questions basic to personal identification** - Are the remains human? - Do the remains represent a single individual or several? - How old was the deceased? - What was the skeletal sex of the deceased? - What was the population affinity (ancestry) of the deceased? - What was the stature, body weight and physique of the deceased? - Are there unique skeletal traits or anomalies that could serve to provide a tentative or positive identification? Who is it? - **Questions regarding the circumstances of death** - When did death occur? - Did the person die at the place of burial, or was he or she transported after death? - Was the grave disturbed, or was the person buried more than once - What was the cause of death? - What was the manner of death? - What was the identity of the perpetrator(s)? **Lecture 6 -- Lab Methods in Forensic Anthropology** - Data gathering methods - **Anthroposcopy** - Looking at qualities (something you cannot have a number on) - Is it small, big, rugged, fragile, etc. - **Osteometry** - **Osteology**: the study of bones; the science that explores the development, structure, function, and variation of bones. - **Osteometry**: the measurement of human bones on an objective scale (Usually in milometers) using calipers and osteometric board - **Tools**: Osteometric board, bow-caliper, & sliding caliper. Osteometric Board - Southern Biological  Amazon.com: Starrett Yankee Spring-Type Caliper with Hardened Fulcrum Stud, Bow Spring and Quick Adjusting Spring Nut - 4\" Size and Capacity, Spring Joint Type - 79A-4 : Industrial & Scientific - **Chemical Methods** - Chemical methods involve measuring the chemical make-up of certain bones - For instance, they can be used to identify poison - Chemical's methods are frequently used in archaeology to reconstructs the diet and health of people (e.g., Stable Isotope) - These methods are costly and complex, and we will not use them in this course - **Histology** - Involves cutting thin sliced of bones and teeth and looking at them under a microscope in order to establish the age of an individual, like chemical methods, we are not going to use them here. - **Data Analysis methods**. - The Decision table  - Range Charts - A range chart combines several sources of information to arrive at a single estimate or conclusion What is Forensic Anthropology? \| Cheshire Anthropology - Indexes - When two measurements express visually identifiable characteristics, you can obtain a single value by dividing one number by the other. This number, when multiplied by 100, yields an index. - Nasal Index= [Nasal width] x 100. Nasal height - \>85% = African Ancestry & \< 70% = Caucasian ancestry  **Lecture 7 -- Human Osteology** **Osteology:** the study of bones; the science that explores the development, structure, function, and variation of bones. - **Why study Human Osteology?** - To be able to identify and process bone material on excavation site - **What are the practical implications of osteology?** 1. Physical description of the living persons (ancestry, age, sex) 2. Evaluation of the health of the person 3. Recognition of habitual activities 4. Identification of the deceased person 5. Recognition of the cause and manner of death 6. Determination of the approximate time since death 7. Information about post-mortem events (following death. Animal scavenging, dismembering...). **Function of Bones** - A bone is a tissue as well as a unit of the skeleton 1. **Support** - Support is the main function of a bone. They support and hold together soft tissues & the muscles of the body. 2. **Protection** - Some bones such as the skull, the rib cage and the pelvis are like an armour. They protect the vital organs of our body. 3. **Movement** - Muscle groups use the mechanical properties of bones to make movements possible 4. **Blood Cell Formation** - The marrow cavities of a bone produce red blood cells **An overview of the human skeleton** - 270 bones at birth; 206 bones during adulthood - Bone of hands and wrists = 27x2 = 54 - Bones of feet and ankles = 26 x 2 = 52 - Total of 106 bones more than half of all human bones - Wrists = 8 bones each. - Ankles = 7 bones each - The skull has 22 different bones - **Some** **bones are unique** - Ex: The Hyoid bones - **Other** **bones are paired** - Ex: Legs, arms, ribs, hips, etc. - Each bone displays several features like projections, depressions, ridges, and various other characteristics - For instance, a **feature** could be a process (projection) on one bone. Fitting with a depression on a second bone to form a joint. Another process allows for the attachment of a muscle - **Cardinal directions when describing human bones** - Superior, inferior, medial, lateral, anterior, posterior, proximal, distal - **The Cranial Skeleton** 1. **Cranial bones (22 bones in total + many more features)** - Some bones are unique while others are paired 2. **Suture lines (has suture written)** - Suture lines separate one cranial bone from another and are usually visible on the surface of the skull 3. **Landmarks (Has abbreviations)** - Landmarks are specific points on the skull used the measure different bones and features in order to obtain standardized and comparable results 4. **Sinuses** - A sinus is a cavity within the skull connecting with the nasal cavities. They are especially located around the face **Lecture 8 -- Human Osteology Part II** - **Axial Skeleton and Thorax** - The axial skeleton is composed of the vertebral column, while the thorax is composed of the rib cage and sternum - **The vertebral column (vertebra = singular, vertebrae = plural)** - The number of vertebrae can vary from one individual another, but normally there are 24 vertebrae divided in three sections: 1. The Cervical Vertebrae (7), 2. The Thoracic vertebrae (12), and the lumbar vertebrae. - NB. Some ass 9 more vertebrae for a total of 33 because they count the ones pertaining to the sacrum (5) and the coccyx (4) - Diagrams start on page 12 of workbook - **In general, a vertebra displays three main features:** - A body - A **Neutral** **Arch** which is further divided in 1) one spinous process, and 2) two transverse processes - Vertebral foramen - **Cervical vertebrae (N=7) (Page 14)** - They include the top seven bones of the spinal column, corresponding to the neck. - The first cervical vertebra connecting to the skull is called the **atlas**. This Vertebra does not have a body - The vertebra below is called the **axis**. It is also different from the others because it displays a protuberance in its superior part called a **dens**. - The other 5 cervical vertebrae are similar to the others in that they have bodies, neural arches, spinous a transverse processes. However, they are easy to identify because they display a hole (foramen) on each transverse process. This hole is called a **transverse foramen**. - **The thoracic vertebrae (Middle of the vertebral column; N=12) (Page 15)** - There are 12 thoracic vertebrae, and they exhibit all of the major structures described previously. However, they don't have the transverse foramen. - The thoracic vertebrae articulate with the ribs - They are easily recognizable because they have a long spinous process that slant inferiorly to the point that they allow for little movement of the upper back - **Lumbar vertebrae (N=5) (Page 16)** - The five lumbar vertebrae are located below the ribs and above the sacrum - They do not articulate with the ribs - They are recognizable by the fact that they have a very large body, and their processes are shorter and wider - **Sternum** - Manubrium: top part of the sternum - Body of sternum - **The Rib Cage** - The rib cage is composed of 12 ribs on each side for a total of 24. They connect or articulate with the vertebrae posteriorly and to the sternum anteriorly. - Each rib has two components: the head and the body - Two floating or false (ribs 11 & 12) - **Appendicular Skeleton (arms, legs, and pelvis) (Page 18)** - The upper limbs (arms and shoulders) - Clavicle (Thick end to the sternum) - The scapula (plural = scapulae) - The spine and the acromion (posterior) - The glenoid cavity (lateral) - The coracoid process (anterior) - **The Humerus (Page 19)** - The head (proximal and medial) - Olecranon fossa (distal + posterior) - The trochlea (distal and anterior) connects the ulna - **The Ulna (Page 20)** - The ulna is the MEDIAL bone of the lower arm. - The olecranon process (proximal of the ulna connects with the olecranon fossa (distal) of the humerus - The cardinal direction of the olecranon processes is posterior - The trochlear notch (proximal) is where the humerus sits on the ulna. It's located anteriorly - The styloid process (distal) of the ulna connects medially with the bones of the wrist - The cardinal direction of the styloid processes is posterior/medial. - **The Radius (lateral bone)** - Head (proximal) - The radial tuberosity. The cardinal direction of the radial tuberosity (proximal end) is anterior/medial - The styloid process (distal end) connects with the wrist on the lateral side - **Wrists and hand** - Carpals: the 8 bones of the wrist - The metacarpals: the 5 bones of the palm of the hand - The phalanges: the 14 bones of the fingers; three in each finger except the thumbs which has only two - **The Pelvis** - The pelvis is composed of **3 bones**: The left and the right os coxae and the sacrum (+ coccyx) - **Os Coxa** (left or right) - The Os Coxa is the result of the fusion of 3 different bones: The ilium, ischium and pubis - The greater sciatic notch (posterior)The pubis symphysis (the medical part of the pubic bone) - The obturator foramen (anterior and inferior) - The acetabulum (hip socket = lateral) - **The Sacrum** - The sacrum is actually the fusion between 5 lumbar vertebrae - **The Coccyx** - The Coccyx is located below the sacrum and is made up of four undeveloped vertebrae that fuse later in life around 25 to 30 years of age - **The Femur** - The head (proximal end and medial) - Lateral and medial condyles (distal end) - Intercondylar fossa (posterior) (used to identify anterior from posterior) - **The Patella** - Kneecap - **The Tibia (medial bone)** - Lateral and medial condyles (proximal) - Intercondylar eminence (proximal) - Tibial tuberosity (anterior) - The malleolus (distal end and medial side) - **The Fibula (lateral bone)** - The head (proximal end and lateral side) - The malleolus (distal end) + lateral/posterior - **The foot** - The tarsals (ankle) = 7 bones - The metatarsals (foot) = 5 bones - The phalanges (toes) = 14 bones **Lecture 9 -- Fieldwork Methods in FA** **Fieldwork in forensic anthropology** - Fieldwork in forensic anthropology simply refers to any investigation taking place outside of the laboratory or office settings. The purpose of fieldwork is to carefully retrieve evidence and information on the crime scene or where the body (or bodies) was discovered. - Fieldwork methods and techniques used by forensic anthropologists have been mainly developed in archelogy. As a result, forensic anthropologists are also trained in archelogy during their graduate studies - Usually, fieldwork involving human remains entails the following steps: A. **Location** - Locating human remains is a mandatory first step of any investigation since without human bones, there is no forensic anthropology investigation - There is no set formula, but a clear search plan should be elaborated. The search plan should address the following issues: 1. **The equipment and personnel** according to budget and time. Several instruments can be used in the field to locate remains. a. If the remains are suspected to be underground, **a ground penetrating radar** can be used. b. **Small planes, helicopters, and drones** can be used to search from the air and cover more territory. c. **Trained dogs** which are sensitive to decomposition smell d. On the ground visual assessment = site survey B. The search for remains and site surveys (Location) a. Organizing a site survey b. Visual clues to look for on the ground i. Increase insect activity and putrefaction smell ii. Vegetation 1. **Buried remains** a. Under a year there will be an empty patch in the in the soil. Over a year there will be a surplus of vegetation in the soil. Compare to surroundings. 2. **Remains located on the surface** b. Under a year there will be an empty patch in the shape of a human in the soil. Over a year there will be a surplus of vegetation in a shape of a human. Compare to surroundings. 3. **Soil colour** c. When you dig a hole and bury a body the soil shoveled in will be a different colour due to the mixing of layers of soil or humidity. 4. **Pile of earth** d. The body in the hole takes space so you will have some excess soil left on the top 5. **Soil compaction** e. The bodies ae usually hidden in shallow graves. In the first year there will be a bump over the body in over to cover all the limbs. After a year the body decomposes and there will be a depression in the hole. C. The search for associated material (still locating but second step) - Circle around the bones found. - Step away and create a bigger area for associated material (evidence) - Once other evidence has been located you put a circle around the bones D. Flag evidence - Flag bones/remains in one colour and physical evidence in another - Flag as soon as you find evidence to avoid leaving something out E. Securing the crime scene - Secure it depending on the size of the crime scene - Purpose: to protect the evidence from being contaminated/losing evidence. F. Mapping remains - Important because you have visual record of it. - It can be used to see how the body was when discovered which can be used to find context about how the person died - Look at the surroundings as well because objects can tell a story of the crime and help you get a bigger picture. - Map everything at the crime scene - The larger the scatter of bones = the longer time since death - **How to make a square grid**: - Select area with most bones - Place 4 stakes around the area with 3 M distance between each stake and wrap string/twine around the area (15 M) - Measure using measuring tape from one side of the square to piece of bone to find points for the grid - Indicate the north with a compass - Indicate the scale (what does one little square on graph represent) - Indicate the date, mapper, case \# (report assignment) - Make a legend on map -- number each drawing on the map and indicate what each piece of evidence is by number in the legend. - Excavations (page 69) - Tools: trowels - Never dig vertically - Remove 5 cm of dirt at a time - Expose the bone(s) - Dig around the bones, don't remove the dirt underneath to avoid moving the bones G. Collecting the remains and bagging evidence - Case number - Date - Name of the individual who picked up the evidence bag number - Content - Evidence number - Bag in paper bags and not plastic because paper bags let the bones breathe whereas plastic bags retain humidity, and the bones will decay overtime. H. Written documentation - Note taking = chain of custody - Write the unfolding of events step by step and describe the crime scene weather - This can help find who is responsible for any mistakes that may occur - Inventory = chain custody - Ensures that the crime scene has not been contaminated I. Visual support (pictures and/or video) - Treat it the same as taking notes of the unfolding of events. - Document everything - Diversity of pictures of different steps. J. Forensic Anthropologists and mass disasters - They are not usually in charge of the case just a part of the identification process - A forensic anthropologist should consider several elements: - Personnel - Medical examiners (give death certificate) - Forensic pathologists (conduct autopsies) - Forensic odontologists (use dental records to identify victims) - Fingerprint specialists - Forensic anthropologists. - Location, mapping and collecting - Gps can be used if there were any present - You don't map natural disasters. Main goal is to recover bodies and identify victims. - Natural disasters caused by humans are mapped from central point to each remain and collected after the distance to body is measured. You not only map bodies but also debris to be able to know how the crash happened (fast, slow, into tree, etc) - Temporary morgue + equipment - Temporary morgue is set up in the closest large building with electricity. They set up autopsy, and identification equipment and a preservation area for bodies. - Victim information - Set up victim center to be able to give families information and gain info about the victims K. Warfare crimes and the excavation of mass graves - Bodies are layered on top of the other - Remove soil horizontally (5cm at a time) - Reveal first layer of bones, map, number and collect each body to the best of your ability. - Continue until grave is emptied Establishing the Forensic Significance - Usually involves a person who has died in the last 50 years without the care of a physician 3 Related Questions or Steps to Consider 1. Are the remains actually bone? 2. Are the bones actually human? 3. Are the remains from a person who has died within the last 50 years? - When the remains fall within 50 years, they are called **contemporary**, if they are more than 50 years old, they are called **noncontemporary**. Contemporary vs. Noncontemporary Bone - 4 main aspects that allow establishing the forensic significance of remains: 1. State of preservation -- qualities, attributes on bones 2. Body modification 3. Personal belongings 4. Conditions of interment State of preservation +-----------------------+-----------------------+-----------------------+ | 7 Characteristics | Noncontemporary | Contemporary | +=======================+=======================+=======================+ | 1. Colour | Dark | Light | +-----------------------+-----------------------+-----------------------+ | 2. Texture | Rough | Smooth | +-----------------------+-----------------------+-----------------------+ | 3. Hydration | Dry | Wet | +-----------------------+-----------------------+-----------------------+ | 4. Weight | Light | Heavy | +-----------------------+-----------------------+-----------------------+ | 5. Condition | Brown | Solid | +-----------------------+-----------------------+-----------------------+ | 6. Fragility | Fragile | Tough | +-----------------------+-----------------------+-----------------------+ | 7. Soft Tissue | Absent | Present | +-----------------------+-----------------------+-----------------------+ 1. Colour - When the bone is in the body, it has a **yellowish white** to **yellowish-brown** tint due to saturation by body fats & fluids. After removal of soft tissue, it begins to dehydrate or dry out and **turns to an off-white colour (ivory)** - However, with time the bones tend to turn to a brown colour. Thus, brown bones are usually older than ivory bones. - Exceptions - Sunlight - Old bones can be very white even though they are old due to exposure of sunlight - Buried Bones - Can be very brown even if they are young bones 2. Texture - Old = rough (sandpaper) - New = smooth - Exceptions - Age: older people loose calcium - Bone diseases: osteoporosis -- loss of calcium - Fossils: smooth because it is stone, but old 3. Hydration - Newer bones tend to be more humid - Older bones tent to be more dry - Exceptions: - The environment - Old bones in swamp will be wet even though they are very old. - Burned bones will dry even though they are young 4. Weight - Young = heavy -- soft tissue, body fluids - Old = light - Exceptions: - Environment in contact with water, bones will be heavy even though they are old - Bone diseases osteoporosis -- loss of calcium means that bones are much lighter even if young - Fossils no soft tissue, much heavier because it is a stone even if it is old 5. Condition - Young = solid contain all minerals - Old = broken - Exceptions - Intensity of animal scavenging if large carnivores break bones, they will not be solid even if the bones are young - Acid soil break bones even if young - Fossils very old, but solid 3 complete because they are stones - Manner of death violent death will cause bones to be broken even if young 6. Fragility - Young = tough -- calcium - Old = fragile - Exceptions: - Corrosive substance breaks down bones even if recent - Acidic soil - Fossils 7. Soft tissues - Young = present - Old = absent - Exceptions: - Humification - Person dies in ice Body Modifications - Artificial limbs - Plastic surgery - Tattoos - Piercings - Braces - Fillings Personal Belongings - Buried with objects - Ww2 soldier noncontemporary - Style of clothing - Wallet -- ID cards Condition of interment 1. Burial arrangement: positioning 2. Burial enclosure: where the body is & material of coffin **Lecture 11 -- Estimating the Time Since Death** A. **The importance of determining the time since death in FA** - With the discovery of human remains, it is crucial to determine the **post-mortem intervals** (noticeable changes on an inanimate body through time): The time that has passed since the moment of death. - In addition of determining the forensic significance of a case, time since death for two main reasons: **1.** It can help find the one potentially responsible for the death. **2.** It can help find the identity of the person - In the first hours after death, medical examiners and forensic pathologists use a variety of techniques to estimate time since death. These include the following: - **Liver Mortis**: visible 2 hours after death, most visible between 8-12 hours. The purple blood pooled towards the center of gravity. - **Algor Mortis**: Starts shortly after death; Lasts 8-36 hours after death. The cooling down of the body after death. The body begins cooling down because when we die, we no longer accumulate heat. - **Rigor Mortis**: Starts 2-6 hours after death and can last 24-84 hours. The stiffening of the body. B. **Forensic Taphonomy** - **Forensic Taphonomy** is the multi-disciplinary study of the stages through which the human body goes from being fresh to being completely skeletonized. - **An overview of decomposition** - **Autolysis**: - Fluids that digest food in your stomach will begin digesting your remains. - **Putrefaction:** - Is when the micro-organisms normally residing in the body tissues begin to proliferate and breakdown biological components. - Because these are no longer fought by the body's defense system, these organisms or bacteria (found mainly in the intestinal system) reproduce and progressively eat the soft tissues of the body - **Elements that may accelerate or slow down the rate of putrefaction and decomposition** - **Insect Activity (forensic entomology):** if body is not easily accessible to insects it will slow down the process. - **Animal Scavenging**: if body is accessible to large animals, it will not last long, if it is accessible to smaller animals then it will last longer. - **Presence of plants (forensic botany):** if fungi grow on the body, it will accelerate the decomposition process. - **Environment**: If the soil is acidic, or wind/water erosion, or exposure to sunlight can all accelerate the putrefaction process. - **Climate**: humid environments will accelerate the decomposition process due to the increase in the presence of bacteria while cold environments will slow down the rate of putrefaction. - **Accessible the previous elements.** C. **Post-Mortem Intervals** - **Surface remains** - Warm and moist climates (Tennessee) - Hot and dry climate (Arizona) - Cold climates - **Buried or submerged remains (tends to slow down the process)** - General observation that remains to be more thoroughly investigated - 1 week on the surface = 2 weeks in the water = 8 weeks underground. - This is due to the fact that buried bodies are not accessible to scavengers, insect activity, and it is in a cooler environment - **Animal Scavenging** - General observation that remains to be more thoroughly investigated: - If only 20% of the bones are found, a post-mortem interval of more than 6 months is indicated. - If 80% of the bones are present, a post-mortem interval of less than 6 months as indicated - **Forensic Entomology** - **Life cycle of flies** - **Within minutes after death** = flies colonize the body and begin laying eggs - **Between 6 -- 40 hours** = the eggs will hatch into larvae (maggots) and begin to feed on the body - **Within 3 -- 10 days** = the larvae (maggots) migrate off the body and bury themselves into the ground near the remains. - **Between 6 -- 18 days** = the larvae (maggots) emerge out of the ground as adult flies and return to the body. The life cycle starts over. - A total life cycle of **9 -- 35** days - **The succession of insects** - **Less than 3 days** = only flies - **Between 3 -- 13 days** = mostly flies but some beetles (the are attracted to the maggots) - **Between 13 -- 25 days** = flies and beetles are relatively equal numbers. - **More than 25 days** = mostly or only beetles - Though forensic entomology is very useful, its accuracy may be affected by the climate and the environments: humidity, dryness, heat and cold all affect insect activity and their life cycles. - **Forensic Botany** - **Amount of plant growth beneath a surface body** - **Less than one year** = no vegetation - **More than a year** = More vegetation compared to the surroundings - Growth rate of vegetation - **Deterioration of clothing** - **Deteriorated in less than one year** = organic material - **Little deterioration after 2 years** = acrylic material - **Little deterioration after 4 years** = polyester - **Body Fluids** - Take a sample of soil that has been soaked by body fluids. - Depending on the chemical reaction you may be able to determine the exact **Lecture 13 -- Reconstructing the Stature** - Early methods to calculate the stature of a deceased individual involved reassembling the entire skeleton and measuring the entire length of the body to arrive at an estimate. - However, later work has shown that there was a strong correlation between living height and bones/or skeletal segments A. **Full Skeleton Method** - One method used to estimate stature involves measuring all the bones responsible for the height of someone. It consists in calculating the length of the bone segments and to sum them up. A correction factor is then applied to compensate for the loss of soft tissues. - The bone lengths that are important to determine stature are the following: 1. The skull height (from Basion/Ba to Bregma/Br) 2. The height of the vertebrae (24) + sacrum (without coccyx) 3. The length of the femur as positioned in the human body 4. The length of the tibia without the intercondylar eminence and malleolus 5. The height of the ankle - Stature can be obtained by summing all these measurements and adding a correction factor to account for. The loss of soft tissue **Calculated Height** **Male** **Female** -------------------------------------- ---------- ------------ 153.5 cm or less 12.2 11.2 Over 153.5 cm and less than 165.4 cm 12.8 11.8 165.5 cm or above 14.0 12.9 - More recent studies have shown that only some of these bones were needed to arrive at a proper estimate (= partial full skeleton method). Actually, **[only the femur and/or the tibia and the lumbar vertebrae are needed]**. The following formulas are then used to calculate stature: - Stature = 47.67 + 2.09 X (femur length + sum of lumbar vertebrae) - Stature = 48.63 + 2.32 X (tibia length + sum of lumbar vertebrae) - Soft tissue correction factors are not needed for this equation. In addition, this stature formula is better adapted to more forensic cases because it requires the presence of less bones. B. **Long Limb Bones Method ([Must have skeletal sex and ancestral group for method])** - Despite that it is less accurate, the most popular technique to calculate stature is with long limb bones. This method originally derived from the simple observation that tall people have longer limbs than shorter people - The calculation of stature with long limbs is done with the help of coefficient table formulas that are added and multiplied to limb lengths in order to get the living height of a deceased person. - Mildred Trotter gathered the most complete data to establish a correlation between the lengths of limb bones and stature. She analysed 5000 individuals who had died during WWII and the Korean war. These individuals belonged to different ancestral populations and included both males and females. - **She came up with several interesting observations**: 1. The bones of the arms and legs, can be used to predict the estimate the living height of a person 2. The right and left limbs are nearly identical and one of the two can be used to calculate stature 3. Long arms often signify long legs and vice versa 4. Dividing the sample by ancestral group and skeletal sex results in more accurate estimate of stature as bone and body proportions tend to differ between different groups 5. Lower limb bones correlate more strongly with stature than upper limb bones 6. The greater the number of long limb bones used to estimate stature the more accurate the estimate will be. C. **Adjustment to stature** 1. It is important to keep in mind that people [lose stature] as they grow older. This is due mainly to the compression of the cartilage between bone joints and collapsing of the vertebral column due to fatigue fractures caused by osteoporosis among others. - The previous formulas do not account for the loss of stature due to aging. If the age of the individual is known, the following adjustment to real stature should be done: Age Category Males (mm) Females (mm) -------------- ------------ -------------- 46-49 3.1 0.1 50-59 7.2 2.8 60-69 16.0 12.5 70+ 32.3 33.9 - Females statistically lose more height 70+ because they are more prone to osteoporosis. - Loss of height for men can be due to heavy factory work causing compression 2. **Post-mortem bone shrinkage** - With decomposition and exposure to the environment, bones lose their fluids and as a result they tend to shrink. - A general figure would be that 10 months after death for surface remains, the skeleton loses 1.5% of its original stature. But this may vary according to the climate. As we know, in tropical and humid environment, the shrinkage takes longer because the bones retain humidity for much longer period of time. 3. **Reported versus measured stature** - Several studies have shown that people tend to declare a higher stature than they really are. It has been shown that males over report their stature by ½ an inch, whereas females over report their stature by ¼ an inch. **Lecture 14 -- Death, Trauma and the Skeleton** A. **Trauma** - A **trauma** is a pathological category defined as an injury caused to living tissues by an outside force - An **outside force** can be produced by a variety of objects normally associated with violent deaths, such as blunt objects, projectiles (bullets), cutting instruments (knife) and chopping tools (axes). - However, [any hard surface may cause trauma]: the ground during a fall; large moving objects such as cars, trains, or trucks, and wreckage during an aircraft accident. - [Chemicals] may also cause trauma on the human body such as highly corrosive substances (acid). [Fire and frost] may also cause damages to bones. B. Trauma and Law