Human Remains Human Remains
Objectives
You will understand: How anthropologists can use bones to determine: Whether remains are human Gender Age Sometimes race Estimated height When the death occurred.
2 Human Remains
Objectives, continued
You will be able to: Distinguish between a male and a female skeleton. Give an age range after examining unknown remains. Describe differences in skull features among the three major racial categories. Estimate height by measuring long bones.
• Performed by a pathologist • Determines the time of death. This can be done most accurately if the body is found within the first 24 hours of death • Uses certain indicators such as algor, livor and rigor mortis. What stops the moment you die?
Livor Mortis
▪ Livor mortis is the pooling of blood in the body due to gravity after the heart stops, resulting in a reddish or purplish color pattern.
▪ Lividity can indicate the position of the body after death. When lividity becomes fixed, then the distribution of the pattern will not change even if the body’s position is altered.
▪ It does not occur in areas that are in contact with the ground or constricted by other objects…the capillaries are compressed in those places • Lividity begins within a half hour after death • Usually becomes fixed (unable to blanche) between 10 and 15 hours after death.
If body is blanchable, it is less than 10-15 hours old Algor Mortis • Algor mortis is the cooling rate of the body after death. • At a crime scene, the body temperature is obtained through: ▪ Liver temperature
Glaister equation: (98.4°F - liver temperature) / 1.5 = hours elapsed since death • Generally the body cools 1 to ½ degrees Fahrenheit per hour until it reaches the surrounding temperature. • Rate of cooling can change depending on the surroundings Algor Mortis
• Additional factors… • Body temperature at the time of death • Mass of the body • Clothing • Obesity • Posture of the body (extended vs. fetal position) Practice Question The body temperature is 82.4 °. How long has it been since death?
(98.4°F - liver temperature) / 1.5 = hours elapsed since death Rigor Mortis
• The rigidity (stiffening) of skeletal muscles after death • Muscles are no longer able to relax, and become “locked” Research of Remains
Bill Bass is a forensic anthropologist who has assisted law enforcement with hundreds of cases. He established the world’s first and only laboratory devoted to the study of human decomposition at the University of Tennessee’s Anthropology Research Facility. It is known as “The Body Farm.”
https://www.youtube.com/watch?v=jiIBpHC7Lfo The Body Farm, 45 The Body Farm The nickname of a two and a half acre research facility in Tennessee developed in 1980 by Bill Bass where bodies are placed in various conditions and allowed to decompose. Its main purpose is to observe and understand the processes and timetable of postmortem decay. Over the years it has helped to improve the ability to determine "time since death" in murder cases.
“Hic locus est ubi mortui viveuntes docent.” This is the place where the dead teach the living. Forensic Anthropology Forensic anthropology is a type of applied anthropology that specializes in the changes and variations in the human skeleton for the purpose of legal inquiry Forensic Anthropology
▪ A forensic anthropologist may provide basic identification information of skeletonized or badly decomposed remains. ▪ From a whole bone or part of a bone, the scientist may be able to estimate: • An age range • Sex • Race • Approximate height • Cause of death, disease, or anomaly
Any ideas how or where to look for these? Osteology
Study of bones 206 bones in an adult human
Function of bones: ▪ Provides structure and rigidity ▪ Protects soft tissue and organs ▪ Serves as an attachment for muscles ▪ Produces blood cells ▪ Serves as a storage area for minerals ▪ Can detoxify the body by removing heavy metals and other foreign elements from the blood
Age Determination Most accurate estimations from: ▪ Cranial sutures: the three major cranial sutures appear as distinct lines in youth and gradually close from the inside out. ▪ Teeth ▪ Epiphyses (bone growth plates)
**Investigators always use an age range because of the variation in people and how they age. Human Remains
22 Human Remains
23 Age Determination Sagittal suture Using Cranial Sutures
Sagittal suture completely closed ▪ Males—26 or older ▪ Female—29 or older Sagittal suture is completely open ▪ Male—less than 32 ▪ Female—less than 35 Complete closure of all three major sutures ▪ Male—over 35 ▪ Female—over 50
Coronal Lambodial Human Remains
-Which Skull Sutures looks unfused?(not sealed shut). Which one Fused?
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Human Remains
Age Determination In long bones, the diaphysis, or shaft, makes up most of the bone’s length. The epiphyses are found at the ends of the bones; their function is to allow for growth. The epiphyses are good places to look for changes in estimating age. Though all people are different and grow at different rates, there are similarities that allow for generalizations in estimating age.
27 Growth Plate (Epiphyseal plate) • Stage 1: Nonunion with no epiphysis (there is no growth plate yet)
• State 2: Nonunion with separate epiphysis (the growth plate is formed but not attached)
• Stage 3: Partial union of the epiphysis (growth plate is beginning to attach to the bone)
• State 4: Complete union of the epiphysis (growth plate is completely attached and smooth) Gender Differences • Gender can be determined by examining: • Pelvis (hip bones) • Skull Features • Relative size of bones • Males are larger than females Gender Differences in Bones: Pelvis
Male Female Shape of Narrower Wider pelvis Pelvis pelvis
Subpubic Smaller than Larger than 90 Angle 90 degrees degrees
Pelvic Inlet More Less obstructed obstructed Other Gender Differences • The ribcage and shoulders of males are generally wider and larger than that of females.
• Skull differences • Smaller frontal • Smaller temporal • Smaller mandible
*Bone markings are more prominent in males Race Characteristics
▪The skull is particularly useful in estimating race if needed
Race Nasal Passage Orbital (Eye) Sockets Asian Rounded Rounded
African Wide Square
Caucasian Narrow Angular Human Remains
What differences do you notice among these three skulls? Can you determine race? (Asian, African, Caucasian)
______
33 Caucasian (Caucasoid)
Angular Oval Orbits
Long, narrow nasal aperture Asian (Mongoloid)
Rounded Orbits
Rounded nasal aperture African (Negroid)
Square Orbits
Wide Nasal Aperture What differences do you notice between these three skulls? Can you determine race? Estimation of Height • The height of a person can be calculated by using the length of long bones. • Femur, humerus, radius and tibia
• Below are the equations to determine average measurements for both male and female. (All measurements are in centimeters)
Male Female .
femur x 2.23 + 69.08 femur x 2.21 +61.41 tibia x 2.39 + 81.68 tibia x 2.53 + 72.57 humerus x 2.97 + 73.57 humerus x 3.14 + 64.97 radius x 3.65 + 80.40 radius x 3.87 + 73.50 Human Remains
Odontology- The Study of Teeth The identity of an individual can be determined by comparing a person’s teeth to his or her dental records. Unusual features including the number and types of teeth and fillings, the spacing of the teeth, and/or special dental work (bridges, false teeth, root canals) help to make a positive identification.
1. Identification of remains 2. Bite mark analysis
39 Human Remains
Odontology and Identification
Teeth are often used for body identification because: They are the hardest substances in the body (they do not readily decompose). They are unique to the individual. X rays are a good record of a person’s teeth, giving them a unique identity.
40 Facial Restoration • Used with unidentified remains • Helps give a proportioning of facial features to help in recognition -Does not give a full accurate depiction of the actual appearance of the deceased.
After determining the sex, age, and race of an individual, facial features can be built upon a skull to assist in identification. Erasers are used to make tissue depths at various points on the skull. Clay is used to build around these markers and facial features are molded. Animal Facial Restoration
Determining what T Rex looked like using the bone formation. From this: To this:
Kendall/Hunt Publishing Company 42 Forensic Entomology Insects as Evidence Forensic entomologists use their knowledge of insects and their life cycles and behaviors to give them clues about a crime. Blow Fly Most insects used in investigations are in two major orders: Carrion Beetle 1 – Flies 2 – Beetles Species succession provide clues for investigators. -Some species may feed on a fresh corpse, while another species may prefer to feed on one that has been dead for two weeks. -Investigators will also find other insect species that prey on the insects feeding on the corpse. Other Factors to Consider
Weather data is also an important tool in analyzing insect evidence from a corpse.
Temperature and precipitation levels affect how insects will develop on the body
Other factors that might affect their estimates: 1. Was the body enclosed in an area or wrapped in a material that would have prevented flies from finding the corpse and laying eggs? 2. Were other insect species present that may have affected the development of the collected species? 3. Were there drugs or other poisons in or on the body that might have affected the larvae’s development?
Did you know? Maggots can be used to test a corpse for the presence of poisons or drugs. Some drugs can speed up or slow down the insect’s development. Blow Fly Metamorphosis
Blow flies are attracted to dead bodies and often arrive within minutes of the death of an animal.
Adult 1st – Adult flies lay eggs on the carcass especially at wound areas or around the openings in the body Pupa Eggs 2nd – Eggs hatch into larva (maggots) in 12-24 hours.
3rd– Larvae continue to grow and molt (shed their exoskeletons) as they pass through the various instar stages. 1st Instar - 5 mm long after 1.8 days 2nd Instar - 10 mm long after 2.5 days 3rd Instar – 14-16 mm long after 4-5 days 3rd Instar 1st Larva Instar 4th – The larvae develop into pupa after burrowing in surrounding soil. Larva 2nd Instar 5th – Adult flies emerge from pupa cases after 6-8 days. Larva It takes approximately 14-16 days from egg to adult depending on the temperatures and humidity levels at the location of the body. Examples of Beetles Early Stage Decomposition Early to Late Stage Decomposition
Carrion Beetles (Silphidae) Adults & larvae feed on fly larvae Rove Beetles Clown Beetles (Staphylinidae) (Histeridae) Predator of fly eggs Predator of fly eggs
Late Stage Decomposition
Ham & Checkered Beetles (Cleridae) Hide Beetles Predator of flies & beetles; (Scarabidae) also feed on dead tissue Skin Beetles (Dermestidae) Usually the last to arrive Feed on dried skin & tissues
Informational Source: http://naturalsciences.org/files/documents/csi_tg_overview.doc Images: http://www.cals.ncsu.edu/course/ent425/library/spotid/coleoptera/coleoptera.html & http://www.forensicflies.com/beetles.htm