Forensic Anthropology Chapter 8

Intro We need to know how people’s osteology is different Can tell age, sex, ancestry, health, activities, during life Helps us identify skeletal remains

Measuring Human Biological Variation Anthropometry: measurement of humans Osteometry: measurement of skeletons To measure people, first step is to identify landmarks Sutures, places on skull that are midline, or those that stick out the most

Anthropometric Techniques Main tools are spreading calipers and sliding calipers We look at head shape, nasal shape Head shape: helpful to determine ancestry Cranial breadth: maximum width of skull Cranial length: maximum length of skull Cephalic: how round or long skull is: Cranial index: (Cranial breadth x 100) / Cranial length Page 183

Anthropometric Techniques Nasal shape: also to determine ancestry Nasal breadth: widest part of nasal opening Nasal height: length of nasal bones (see diagram) Nasal Index: (Nasal breadth x 100) / Nasal height Page 183

Determining Sex Use pelvis and skull Sexual dimorphism: differences in size or shape between sexes of a species Males: more rugose (rugged muscle attachments), larger bodies, narrow pelvis, square chin, large brow ridges Females: smaller bodies, more slender bones and muscles, wilder pelvis, round chin, small brow ridges There is variation! Charts on page 189 will help

Assignment Lab 8.2 Use pictures in book and skulls on table to fill in charts Self-Test 8.2 on own

Determining Age Formative changes (from growth) and degenerative changes (from old age) help determine age at death Look at dentition, sutures and growth rates Usually get age ranges, not exact age

Determining Age Using dentition: Look at growth of tooth enamel, which grows at regular rate Growth patterns of tooth root Dental eruption: most common; useful through age 15; remember dental formula of 2-1-2-3

Determining Age Using sutures: Epiphyseal Closure: after birth, bone grows in “plates” connected by cartilage Later, the bone ossifies and cartilage replaced by bone These bones fuse at intervals that can help determine age Last bone to fuse is clavicle, no later than 28 years Chart on page 196 shows ages of bone closure

Degenerative Changes In adulthood, bones are fused and wear and tear becomes observable Cranial sutures: as skull grows, sutures become worn smooth Pubic Symphysis: the “face” changes with age; ridges wear down; evidence of childbirth Dental attrition: the occlusal surface of teeth wear down. This is impacted by type of diet

Assignment Lab 8.1 Use skulls!!!! Do Self-Test 8.1 on own Lab 8.2 Last but not least, Zoo info…..

How Tall Were They? Height/stature can be reconstructed by measuring bones Use an osteometric board to measure Actual height can differ from last recorded height because of inaccuracy, shrinkage with old age, etc.

Assignment Lab 8.4 #1-4 Use previous measurements for #1 Self-Test 8.4 on own

Extra Credit WS Remember to look for clues in wounds for what type of weapon (sharp, blunt, gunshot, etc.) was used Gunshot wounds show direction If there is any evidence of healing, you cannot say that the injury killed the person (SO LOOK FOR HEALING!!) For crime scene, use the chart of epiphyseal fusion, dental eruption, and anything from book or notes