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AnthropologyAnthropology

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.

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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.

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Osteoclasts, the 3rd type of bone cell, among other tasks, remove cellular wastes.

– Ex. Broken bones

After wastes are removed, osteoblasts can form new bone

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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.

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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

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What Bones Can Tell Us 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?

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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

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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

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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

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Gender

Female Male

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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↑

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Subpubic angle is greater than 90° in females Angle is less than 90° in males. (50-85°)

Female Male

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FemaleMale

Coccyx

Width of ileum

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How to determine age of a skeleton

By about age 30, the suture at the back of the skull will have closed.

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By about age 32, the suture running across the top of the skull, back to front, will have closed.

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By about age 50, the suture running side to side over the top of the skull, near the front, will have closed.

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If the skull is manipulated beforefull growth, weird shapes canbe made.

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31 week fetus

32 week fetus

Newborn baby

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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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Skeletal differences according to raceCaucasoid Negroid Mongoloid

Shape of eye orbits

Rounded, somewhat square

Rectangular Rounded, somewhat circular

Nasal spine Prominent Very small Somewhat prominent

Nasal Index <0.48 >0.53 0.48-0.53

Prognathism Straight Prognathic Variable

Femur Fingers fit under curvature of femur

Fingers don’t fit under curvature

Fingers will fit under curvature of femur

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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.

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Skeletal Trauma Analysis 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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To calculate height for Afro-American and African females– Height(cm) = 2.28 x length of femur + 59.76cm

To calculate height for Afro-American and African males:– Height(cm) = 2.10 x length of femur + 72.22cm

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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

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. . . . . . . . . . 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.

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. . . . . . . . . . . . . . . . . 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.