Forensic Anthropology Pawson PVMHS, 2015

Student objectives: At the end of the unit, you should be able to: Analyze skeletal remains to determine race, sex, age, & height Define osteobiography Discuss how facial reconstruction is done using skull bones Demonstrate how to determine approximate age of a victim based on their teeth Identify 23 bones in the human body Identify and explain the meaning of an epiphyseal line Determine the estimated age of a person by examining the suture marks of the skull Discuss the relationship between mDNA and bone

Need to know bones: Skull Pelvis Mandible Sacrum (tail bone) Hyoid bone Femur Vertebral column Patella Ribs Tibia Sternum (breast bone) Fibula Scapula Tarsals Clavicle Metatarsals Humerus Phalanges of the foot Radius Ulna Carpals Metacarpals Phalanges of the hand

“Anthropology” Anthropology is the study of all aspects of human development and interaction Ex: When I worked in a lab, we had anthropology students that would sit in lab and “study” us. Physical anthropology – studies the physical characteristics of humans. Forensic anthropology – studies the physical characteristics of deceased humans.

What can bones tell us? Osteobiography—bones contain a record of the physical life. This is the osteo (bone) biography. Analyzing bones reveals clues to gender, age, height, and health 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 Catacomb: an underground passageway that serves as a religious cemetery. Paris

Bones – are they alive? Your bones are living tissue with blood flowing to them. Bones grow from cells called osteoblasts. Osteoblasts migrate to cartilaginous areas and deposit minerals, hardening into bone. This is called ossification. Bones are regularly broken down and regrown as calcium is re-deposited. Compact bone: solid/hard Spongy bone: porous Contains red marrow

Classification of bones: Long bone Longer than it is wide Short bone Generally cube like shape Contain spongy bone Flat bones Flat and thin (ex. skull bones) Compact bone surrounding spongy bone Irregular bones Irregular in shape (ex. vertebrae)

♫ Your hip bone is connected to your thigh bone…♬ Cartilage covers the ends of your bones Anywhere one bone meets another bone there is cartilage. This prevents the bones from rubbing against one another This includes between your skull bones (sutures), your vertebrae (discs), your ribs, etc. Bones are held together by ligaments. Muscles attached to bones by tendons.

The skeleton The adult human body has 206 bones, you will learn to identify 23 of these bones. The skull, vertebral column, and rib cage make up the axial skeleton. The limbs, pectoral girdle, and pelvic girdle make up the appendicular skeleton.

Hyoid bone This is the only bone that does not articulate with another bone It is attached to the skull by ligaments, and serves as a moveable base for the tongue. This bone is significant to forensics because fractures in the hyoid bone are indicative of hanging or strangulation.

Sutures and epiphyseal plates There are areas on your bones that are not fully ossified (hardened) yet. These areas contain cartilage and exist so that you can continue to grow. These areas close at specific ages. Studying these areas can help an anthropologist determine the age of a skeleton. One suture on the skull doesn’t close until a person is in their 50s. Closes at 30 Closes at 32 Closes at 50

Epiphyseal Plates Bones grow throughout puberty, epiphyseal cartilage appears at the growth plates and epiphyseal lines are visible on X-rays. This will eventually close and disappear as the individual matures.

Determining age A person’s age can be determined using the information that sutures and epiphyseal plates provide.

Your teeth Composed of enamel and dentin Baby teeth Dentin is similar to bone Enamel is the hardest substance in the human body Baby teeth As children 20 primary teeth come in following a predictable pattern beginning in the first 7 to 12 months of life. The last teeth to develop are the wisdom teeth which appear between the ages of 17 to 21. The complete adult set of teeth includes – eight incisors, four canines, eight premolars, and 12 molars. 32 total teeth.

Your teeth

Your skull The skull is made up of 8 cranial bones and 14 facial bones. The mandible is attached by ligaments. There are cavities in your frontal, ethmoid, sphenoid, and maxillary bones – these are your sinuses.

Facial reconstruction 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 facial reconstruction University of Dundee, Scotland

Skeletal trauma analysis Forensic anthropologists often have to determine if damage occurred to bones before or after death Distinct patterns exist for damage by Environment Sharp-force trauma Blunt-force trauma Gunshot wounds Knife wounds

Types of bone fractures

Determining 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 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

Determining gender: Skull Is the female skull smoother than the males? Which frontal bone is lower and sloping? Are the males eye orbits more circular? Which jaw is more square, with an angle that is closer to 90o?

Determining gender: Pelvis If the pelvis is available, this is the easiest way to determine gender. Differences between the male and female include: Subpubic angle Female is greater than 90° the male’s is less than 90° Size and shape of pelvic inlet (opening in the middle of the pelvis) Width and size of the ileum These differences would not be obvious in pre- pubescent children.

Determining gender: Pelvis

Determining gender: Femur Because of the differences between the male and female pelvis, the femur joins the pelvis at a different angle on male and female skeletons. The male femur is likely to be thicker. This is because men tend to have larger muscles. The gluteus maximus, gluteus medius, and adductor muscles all attach to the femur. The more muscle or stronger the muscle, the stronger the bone. This is why weight bearing exercise decreases the chance of osteoporosis.

Determining gender: Femur

Determining height Measuring the long bones (like the humerus or femur) can help determine the approximate height of a person. Gender and race need to be taken into consideration when making determinations. Pg. 371 in text has a chart showing mathematical formulas to determine height for using various bones and taking race and sex into consideration.

Determining race This can be very difficult in a society where there is a high level of blended physical traits. Some differences between races include: Shape of eye sockets Absence or presence of a nasal spine Measurements of the nasal index (ratio of width of nasal opening to height x 100) Prognathism (projection of upper jaw, maxilla, beyond lower jaw, madible) Width of face Angle of jaw and face

DNA evidence from skeletal remains Your cells contain 2 types of DNA Nuclear DNA Mitochondrial DNA Mitochondrial DNA is located in the mitochondria of your cells Mitochondrial DNA comes from your mother only Nuclear DNA degrades faster than mitochondrial DNA, so usually nuclear DNA cannot be retrieved from bone. Mitochondrial DNA can sometimes be retrieved and comparisons can be made with living relatives on the mother’s side.

Any questions??