5/4/2015. Vocabulary. Characteristics of Bone. Historical Development. Development of Bone. Development of Bone

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1 Chapter 13 Forensic Anthropology: What We Learn from Bones By the end of this chapter you will be able to: Vocabulary describe how bone is formed distinguish between male and female skeletal remains explain how bones contain a record of injuries and disease describe how a person s approximate age, height, race, and background could be determined discuss the role of mitochondrial DNA in bone identification Anthropology the scientific study of the origins and behavior as well as the physical, social, and cultural development of humans. Tools, language, traditions, societal relations, etc. Forensic anthropology studies these identifying characteristics on the remains of an individual 1 All Rights Reserved South-Western / Cengage Learning Historical Development Characteristics of Bone 3 1. In Europe in the 1800s, scientists began studying skulls. This laid the framework for today s knowledge. Male v. female, formation, aging & fusing of bones 2. In 1932 the FBI opened the first crime lab. 3. The Smithsonian Institution became FBI s partner in the identification of human remains , text on how to ID skeletal material. 5. Soldiers killed in World War II were identified using anthropologic techniques. 6. Recently, mitochondrial DNA used to ID remains. 4 Bones carry on cellular respiration and use energy. Blood cells are made in the bone marrow inside of bones Regulated by hormones that affect calcium in blood and in bones. Osteoporosis weakening of bone, may happen if there is not enough calcium in the diet and the body takes it from the bones to compensate. Development of Bone Development of Bone 5 Bones begin as soft cartilage & come from cells called osteoblasts. They migrate to center of cartilage production & deposit minerals that harden - ossification. Begins during the first few weeks of pregnancy, by 8th week, an outline of a skeleton can be seen on x-rays. Throughout life, bones are being broken down, deposited, and replaced. Osteocytes (living bone cells) are osteoblasts that are trapped when bone is broken and begin to heal it. 6 Osteoclasts, the 2 nd type of bone cell, among other tasks, remove cellular wastes and dissolve bone if needed. Adults have 206 bones. Babies have 450 bones because they are not fused completely yet. 1

2 Louise Luetgert murder How Bones Connect 7 Research the murder of Louise Luetgert including: A summary of the case Description of how bones are involved Defense attorney s claims Outcome of the trials 8 Joints-locations where bones meet- have: a. cartilage wraps the ends of bones and keeps them from scraping one another. b. ligaments bands that connect two or more bones together. c. tendons connect muscle to bone. Until about 30 years of age, bones increase in size. Deterioration after 30 can be slowed with exercise. What Bones Can Tell Us Skull Cleaner Osteobiography tells much about a person through the study of the skeleton. The bones of a right-handed person, for example, would be slightly larger than the bones of the left arm. Bones contain a record of the physical life. Analyzing bones can reveal clues to such things as gender, age, height, health, type of sports they play, nutritional deficiencies. Sometimes bones are exposed, other times they need to be cleaned Dirty Jobs Skull Cleaner 9 10 Female skeletons tend to be smoother (gracile) and less knobby than a male s (robust). Surface of the bone where muscle and tendons attach is thicker in males. Male skull is more massive and bumpier Male frontal bone is low and sloping, eye orbit tends to be square, lower jaw is square with an angle close to 90 o, chin is more square. Males brow ridge is thicker and larger. Males have occipital protuberance on the back of their skulls due to thicker neck muscles. One of the easiest methods of determining the gender of a skeleton is the pelvis. The surface of a woman s pelvis can be scarred if she had children. The sub pubic angle of the female pelvis is 90 o or greater; the male s, less. Female sacral region is shorter, broader, curved outward. Females have oval shaped pelvic cavity, Male is heart-shaped

3 Bones and Sports Female pelvis weighs less On a sheet of paper The width of the ileum and the angle of the sciatic notch are also compared The angle of the femur in relation to the pelvis is greater in females and straighter in males. Male femur is thicker Compare and contrast the bones of someone who plays football to someone who plays soccer Compare and contrast Coach Viscounte s bones to that of a female fashion model. Why could using steroids to build muscle cause bones to break Look for presence/absence of cartilage By about age 30, the suture at the back of the skull (lamboidal) will have closed. By about age 32, the suture running across the top of the skull (sagittal), back to front, will have closed. By about age 50, the suture running side to side over the top of the skull (coronal), near the front, will have closed. 450 bones in a baby fuse forming 206 in an adult. As the cartilage between them is replaced by bone, a cartilaginous line is visible - epiphysis. When the cartilage is fully replaced, the line is no longer visible. of completion of growth is different for each bone. End of a long (femur, humerus) bone also fuses to its shaft at different ages Height 17 Region Bone (for fusion of end to shaft) Arm Humerus Leg Femur Shoulder Clavicle/sternum Pelvis All sacral bones Skull Sutures closed Looking at the bones of the arm and leg, can also give an estimate of height. The approximate height of a person can be calculated from just one of the long bones. Separate tables for type of bones used, males/females and different races. Knowing gender and race will make estimate much more accurate. 3

4 Distinguishing Race Other characteristics Losing its significance due to blending of physical traits. Best indicated by the skull and femur Skull shape of eye socket, ratio of width to height of nasal opening, projection of upper jaw over lower jaw, width of face Bones can also show 1. Diet/nutrition, especially lack of vitamin D & calcium 2. Diseases and genetic disorders, arthritis, scoliosis 3. Previous fractures 4. Types of work/sports 5. Surgical implants 6. childbirth Theoretically, a face can be rebuilt from just skeletal remains since the shape of the bones relates to the shape and size of muscles and tissues Wilhelm His used skull of Bach to reconstruct his face in clay. His measurements of tissue depth are the basis of facial reconstruction 22 Facial markers are positioned at critical locations on a skull, and clay is contoured to follow the height of the markers. Today, computer programs perform a similar function. Faces allows facial reconstruction from the image of a skull; hairline, hair style and other details can be modified. These computer programs also can age missing persons and criminals. Face Transplant Video-superimposition matches a photo of someone to their remains for ID purposes. Facial landmarks are measured and overlaid on a photo of the skull for comparison Surveillance cameras can also use these measurements to catch criminals Facial recognition software While a medical marvel, face transplants will never look the same because of the relationship between the skull bones and the muscles and tissues. Face transplant video

5 NOVA DNA Evidence Alien from Earth Bone contains little nuclear DNA. It does contain mitochondrial DNA. This is DNA that is inherited only from the mom. Long after nuclear DNA has been lost through tissue degeneration, mitochondrial DNA can be obtained from bone. Results can be compared with living relatives on the mother s side of the family to identify skeletal remains Skeletal Trauma Analysis Skeletal Trauma Analysis 27 Forensic anthropologists often determine if damage to bones occurred before or after death. Definite distinctions exist between patterns on bones made by weapons and the patterns created by the environment after death. Sharp-force trauma, blunt-force trauma, gunshot wounds, and knife wounds all have distinctive patterns. 28 Knife wounds leave parallel marks on rib bones, but rodent chew marks look very similar Skeletal trauma analysis investigation of bones & marks on them to determine cause of death. Blunt and sharp force marks have different shatter pattern and amount of impact damage to the bone Blunt force have cracks radiating from impact site and more damage to surface of bone Living bones will shatter in a spiral pattern parallel to the length; old bones break perpendicular to the length 5