Forensic Anthropology In Forensics, analyzing bones is important for identification of a possible victim or suspect. Forensic Science: Fundamentals & Investigations, Chapter 13

Forensic Anthropology Anthropology— The scientific study of the origins and behavior as well as the physical, social, and cultural development of humans. Study tools, languages, traditions, and social interactions Physical anthropology—studies human differences Forensic anthropology—studies these identifying characteristics on the remains of an individual These characteristics can be used to help identify gender, race, height, and physical health of the victim Forensic Science: Fundamentals & Investigations, Chapter 13

Historical Development Soldiers killed in World War II are identified using anthropologic techniques DNA—new tool to analyze skeletons DNA found in the mitochondria of the cells Forensic Science: Fundamentals & Investigations, Chapter 13

Characteristics of Bone Bones are alive They breath via cellular respiration and consume energy like any other living cell Marrow—creates blood cells Bones are regulated by hormones that effect the amount of calcium in the blood and the hard part of bones Forensic Science: Fundamentals & Investigations, Chapter 13

Development of Bone Bones originate from a cell called osteoblast. During development of the fetus, bones begin as soft cartilage Ossification then occurs this is when the cell Osteoblast migrate to the center of the cartilage and deposit minerals, such as calcium phosphate that hardens to become bone Occurs during the first few weeks of pregnancy Forensic Science: Fundamentals & Investigations, Chapter 13

Development of Bone By the 8th week of pregnancy the outline of the skeleton has formed and can be seen by x-ray As bone develop, a protective membrane called periosteum, keeps the bone moist and aids in the repair of injuries Forensic Science: Fundamentals & Investigations, Chapter 13

Development of Bone Life cycle of bone is : bone is deposited, brakes down, and replaced When an arm or leg is broken, the blood vessels at the area increase calcium phosphate deposition to help heal the break Newly trapped osteoblast (where bones originated from) are now called osteocytes and they form the new bone framework Forensic Science: Fundamentals & Investigations, Chapter 13

Development of Bone Osteoclast (the 2nd type of bone cell) dissolve bones As layers and layers of calcium phosphate are adding to a growing bone it may not hold its shape Osteoclast secrete enzymes that help dissolve certain areas of the bone Osteoclast removes cellular waste and debris from bone When bones become injure it dissolved the injured part so new bone can grow Forensic Science: Fundamentals & Investigations, Chapter 13

Development of Bone Osteoporosis – weakening of bone, which may happen if there is not enough calcium in the diet Forensic Science: Fundamentals & Investigations, Chapter 13

How Bones Connect Joint is the location where bones meet Joint contain three kinds of connective tissue Cartilage Ligaments Tendons Forensic Science: Fundamentals & Investigations, Chapter 13

How Bones Connect cartilage—wraps the ends of bones for protection and prevents scraping Forensic Science: Fundamentals & Investigations, Chapter 13

How Bones Connect ligaments—bands that connect two or more bones together Forensic Science: Fundamentals & Investigations, Chapter 13

How Bones Connect tendons—connect muscle to bone Forensic Science: Fundamentals & Investigations, Chapter 13

Aging of Bone Before the age of 30 bones are being made at a faster rated than that of bones being broken down – bone growth After 30 the process reverses Bones deteriorate faster than what they are being built Exercise slows deterioration Without exercise bones can becomes frail and less dense, prone to braking Forensic Science: Fundamentals & Investigations, Chapter 13

What Bones Can Tell Us Osteobiography—The physical record of a person’s life as told by his or her bones Examples: In a right-handed person, right arm bones might be slightly larger than the bones of the left arm X-rays may identify prior fractures, pins, artificial joints Forensic Science: Fundamentals & Investigations, Chapter 13

What Bones Can Tell Us The number of bones and their conditions can tell an investigator about a person’s: age health whether they had enough calcium in their food Forensic Science: Fundamentals & Investigations, Chapter 13

Gender Determination from Bones The over appearance of female skeleton tends to be much smoother than male which tent to be more knobby or robust A males skeleton is usually thicker, rougher, and appears quite bumpy Bones are thicker because male hormones and bigger muscles need a bigger bone to hold to Forensic Science: Fundamentals & Investigations, Chapter 13

https://youtu.be/Nc5IRj3OJhE 1- Coronal Structure 2- Frontal bone 3- Nasal bone 4- Maxilla 5- Mandible 6- Zygomatic complex 7- Occipital protuberance 8- Lambdoid suture 9- Parietal bone 10- Squamous suture 1- Mandible 2- Maximila 3- Zygomatic 4- Orbits of the eye 5- Coronal suture 6- Frontal 7- Parietal 8- Temporal 9- Nasal 10-Vomer Forensic Science: Fundamentals & Investigations, Chapter 13

Gender - Skull The male skull is bigger and bumpier than female skull The male’s lower jaw is square with an angle of about 90 degree The female’s lower jaw is sloped with an angle grater than 90 degree Male’s chin also tend to have square chins while Female’s tend to have rounder more V-shape chin Forensic Science: Fundamentals & Investigations, Chapter 13

Female Characteristics Gender—Skull Male Characteristics Trait Female Characteristics More square Shape of eye More rounded Mandible shape from underside More V-shaped Thick and larger Upper brow ridge Thin and smaller Forensic Science: Fundamentals & Investigations, Chapter 13

Female Characteristics Gender—Skull Male Characteristics Trait Female Characteristics Present Occipital protuberance Absent Low and sloping Frontal bone Higher and more rounded Rough and bumpy Surface of skull Smooth Straight Ramus of mandible Slanting Nuchal crest ↑ ↑ ↑ ↑ Forensic Science: Fundamentals & Investigations, Chapter 13

Gender—Skull Is the female skull smoother than the male’s? yes Which frontal bone is lower and sloping? male Are the male’s eye orbits more circular? no Which jaw is more square, with an angle that is closer to 90o?

Gender—Pelvis Using the pelvis is one of the easiest method to identify the gender of skeleton remains The surface of a woman’s pelvis will appear to have scares if she has given birth before During the 4th month of pregnancy tendons in the pelvic are soften by hormones preparing for the birth Forensic Science: Fundamentals & Investigations, Chapter 13

Gender—Pelvis 1- Joint 2- ileum 3- Sacrum 4- Coccyx 5-Joint 6- Ischium 7- Pubis symphysis 8- Obturator foramen Forensic Science: Fundamentals & Investigations, Chapter 13

Gender—Pelvis The sub pubic angle of the female pelvis is greater than 90o; the male’s is less The female pelvic cavity has an oval shape with the sacrum shorter, broader, and curved outward The male Pelvic cavity has a heart shape, with a sacrum that is longer, narrower, and curved inward Forensic Science: Fundamentals & Investigations, Chapter 13

Gender—Thigh bones The male femur is thicker and joins the pelvis at a straighter angle than the female femur Forensic Science: Fundamentals & Investigations, Chapter 13

Determining age The age of a person can be determine by examining particular bones and by looking for the presence or absence of cartilage The skull is used because of the appearance of suture mark that close at different age As ossification (hardening of bones) happens the suture marks disappear Long bones can also be used to determine age by analyzing if its fused to the shaft Forensic Science: Fundamentals & Investigations, Chapter 13

Age—Skull By about age 30, Lambdoidal suture, the suture at the back of the skull closes The closing begins at age 21 and accelerate at age 26 By about age 32, Sagittal suture, the suture running across the top of the skull, back to front, closes By about age 50, the Coronal suture, the suture running side to side over the top of the skull, near the front, closes Forensic Science: Fundamentals & Investigations, Chapter 13

Age—Skull Forensic Science: Fundamentals & Investigations, Chapter 13

Age https://youtu.be/xXgZap0AvL0 At birth—450+ bones in the skeleton Adults— 206 bones Epiphysis line—appears where cartilage is replaced by bone When the cartilage is fully replaced, the line is no longer visible This information can be used to approximate a skeleton’s age Forensic Science: Fundamentals & Investigations, Chapter 13

Age—Epiphysis Forensic Science: Fundamentals & Investigations, Chapter 13

Age— Epiphysis Forensic Science: Fundamentals & Investigations, Chapter 13

Age As infant - more cartilage and less calcium phosphate is present, there are more bones that will eventually grow and fuse together. Ossification is the process of bone growth, old bone and cartilage is broken down and replaced by cells called osteoblast They secrete enzymes that dissolve old bone before the new one can be lay down The calcium phosphate needed to strengthen bone is delivered by the blood vessels Forensic Science: Fundamentals & Investigations, Chapter 13

Height   Forensic Science: Fundamentals & Investigations, Chapter 13

How to Distinguish Race Shape of the eye sockets Absence or presence of a nasal spine Measurements of the nasal index The ratio of the with of the nasal opening to the height of the opening, multiplies by 100 Prognathism The projection of the upper jaw, or maxilla, beyond the lower jaw Width of the face Angulation of the jaw and face Forensic Science: Fundamentals & Investigations, Chapter 13

Eye orbit: Nasal index: Femur: African – rectangular Asian – rounded (circle) Caucasian – rounded (square) Nasal index: African – >0.53 Asian –0.48-0.53 Caucasian – < 0.48 Femur: African – fingers don’t fit under curve Asian –fingers will fit Caucasian – fingers will fit Forensic Science: Fundamentals & Investigations, Chapter 13

Facial Reconstruction https://youtu.be/HxZ4wcTQrx4 Facial muscles follow the contour of the skull A face can be rebuilt from just skeletal remains Facial markers are positioned at critical locations Clay is contoured to follow the height of the markers Computer programs perform a similar function Computer programs also can “age” missing persons and criminals Forensic Science: Fundamentals & Investigations, Chapter 13

DNA Evidence Bone contains little nuclear DNA but it does contain mitochondrial DNA Mitochondrial DNA is DNA found in the mitochondrial that is inherited only through mothers Nuclear DNA degenerates before mitochondrial DNA Compare results with living relatives on the mother’s side of the family http://www.australiangeographic.com.au/topics/science-environment/2015/06/forensics-inside-the-bone-lab Forensic Science: Fundamentals & Investigations, Chapter 13

Skeletal Trauma Analysis Bones exposed to the elements for long period of time are often damage by wreathing and animals Forensic anthropologists determine if damage to bones occurred before or after death Distinct patterns exist for damage by Environment Sharp-force trauma Blunt-force trauma Gunshot wounds Knife wounds Forensic Science: Fundamentals & Investigations, Chapter 13

Skeletal Trauma Analysis Skeletal trauma analysis attempts to make distinctions between the patterns caused by weapons and the damage and wear cause by environment The strength of bones decreases as it ages and dries out Living bones usually shatter in a spiral pattern parallel to the length; old bones often beak perpendicular to the length Forensic Science: Fundamentals & Investigations, Chapter 13

Blunt force trauma Gunshot Sharp force trauma Forensic Science: Fundamentals & Investigations, Chapter 13