Forensic Science: Fundamentals & Investigations, 1 Anthropology In 1932 the FBI opened the first crime lab. The Smithsonian Institution became its working partner in the identification of human remains. Soldiers killed in World War II were identified using anthropologic techniques.

Forensic Science: Fundamentals & Investigations, 2 Development of Bone Bones originate from cells called osteoblasts. The process of bone formation is known as ossification. Once these cells become bone, they are called osteocytes. Throughout life, bones are being broken down, deposited, and replaced.

Forensic Science: Fundamentals & Investigations, 3 Osteoclasts, the 3 rd type of bone cell, among other tasks, remove cellular wastes. – Ex. Broken bones After wastes are removed, osteoblasts can form new bone

Forensic Science: Fundamentals & Investigations, 4 How Bones Connect Bones are held together by: 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.

Forensic Science: Fundamentals & Investigations, 5 Osteoporosis Condition in which bones continually get weaker. Bones fracture and break easier Most common in women after menopause Decrease occurrence with diet high in calcium

Forensic Science: Fundamentals & Investigations, 6 What Bones Can Tell Us 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. Why?

Forensic Science: Fundamentals & Investigations, 7 Forensic scientists realize that bones contain a record of the physical life. Analyzing bones can reveal clues to such things as gender, age, height, and health. – Examples – Poor teeth often means poor nutrition or no access to medicine – Lift heavy objects = thicker bones

Forensic Science: Fundamentals & Investigations 8 How to tell gender? Female – Skeleton is much smoother and not as knobby – Skull is smoother – Eye sockets are more rounded – No occipital protuberance – Jaw is angled more than 90 degrees

Forensic Science: Fundamentals & Investigations, 9 How to tell gender? Male – Skeleton is thicker and rougher More muscle, need more bone – Skull is more massive and bumpier – Eye sockets are more square – Occipital protuberance is present – Jaw angle is about 90 degrees

Forensic Science: Fundamentals & Investigations, 10 Gender Female Male

Forensic Science: Fundamentals & Investigations, 11 Gender One of the easiest methods of determining the gender of a skeleton is by examining the pelvis. The surface of a woman’s pelvis can be scared. Hormones soften pubic symphysis during pregnancy Pubic Symphysis ↑

Forensic Science: Fundamentals & Investigations, 12 Subpubic angle is greater than 90° in females Angle is less than 90° in males. (50-85°) FemaleMale

Forensic Science: Fundamentals & Investigations, Chapter Female Male Coccyx Width of ileum

Forensic Science: Fundamentals & Investigations 14 How to determine age of a skeleton By about age 30, the suture at the back of the skull will have closed.

Forensic Science: Fundamentals & Investigations, Chapter By about age 32, the suture running across the top of the skull, back to front, will have closed.

Forensic Science: Fundamentals & Investigations, Chapter By about age 50, the suture running side to side over the top of the skull, near the front, will have closed.

Forensic Science: Fundamentals & Investigations, Chapter If the skull is manipulated before full growth, weird shapes can be made.

Forensic Science: Fundamentals & Investigations, week fetus 32 week fetus Newborn baby

Forensic Science: Fundamentals & Investigation 19 How to determine Age During life, many of the 450 bones a person has at birth grow together, finally forming 206 bones. As the cartilage between them is replaced, an epiphysis line is visible. When the cartilage is fully replaced, the line is no longer visible. This information can be used to approximate a skeleton’s age.

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Forensic Science: Fundamentals & Investigations 21 Skeletal differences according to race CaucasoidNegroidMongoloid Shape of eye orbits Rounded, somewhat square RectangularRounded, somewhat circular Nasal spineProminentVery smallSomewhat prominent Nasal Index<0.48> PrognathismStraightPrognathicVariable FemurFingers fit under curvature of femur Fingers don’t fit under curvature Fingers will fit under curvature of femur

Forensic Science: Fundamentals & Investigations 22 Facial Reconstruction A face is formed by the skull with the muscles and tissues on top of the skull. Theoretically, nonetheless, a face can be rebuilt from just skeletal remains. Facial markers are positioned at critical locations on a skull, and clay is contoured to follow the height of the markers.

Forensic Science: Fundamentals & Investigations, Chapter Skeletal Trauma Analysis 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.

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Forensic Science: Fundamentals & Investigations 25 To calculate height for Afro-American and African females – Height(cm) = 2.28 x length of femur cm To calculate height for Afro-American and African males: – Height(cm) = 2.10 x length of femur cm

Forensic Science: Fundamentals & Investigations, Chapter Let’s find out how long your femur is!! First have a friend measure your height in centimeters. Write this down. Subtract the **.**cm number from the previous slide Then divide your height by the correct 2.** factor from the previous slide Now you have an estimate of your femur length! Once you have your number, put it on the board along with your height

Forensic Science: Fundamentals & Investigations Summary Summary Bones are alive and carry on all life functions. The condition of bones can tell investigators about a person’s health and nutrition during life. Male and female skeletons differ in many ways. The age of a person at death can be estimated by analysis of a number of bones.

Forensic Science: Fundamentals & Investigations Summary Summary A person’s height can be estimated by the length of long bones. Facial reconstruction is possible to some extent. Mitochondrial DNA can be extracted to help identify skeletal remains. Skeletal trauma analysis examines bones for evidence of damage.