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Unit 9 Anthropology & Odontology Students will explore characteristics of physical evidence and remains. Joseph Merrick, Proteus Syndrome Joseph Merrick “Elephant Man” skeleton Forensic Anthropology Forensic Anthropology is a branch of anthropology which specializes in the human skeletal system for the purposes of identifying unknown remains. Forensic anthropologists study skeletal remains whose identities and circumstances of death are unknown or questionable. They analyze bodies that have decomposed, been badly burned, or have become mummified or skeletonized. Forensic Anthropology Using forensics, the following questions can be answered: Are remains human Are the remains of one individual or are they of mixed remains When did death occur Was the body disturbed after death What are the gender, age, and race of the individual What caused death What kind of death was it… homicide, suicide, accident, natural or undetermined… Are there any anatomical peculiarities, signs of disease, or old injuries Individuals height, body weight, physique can be estimated Skeleton Terms to Label Vertebrae Carpals Patella Phalanges Radius Femur Humerus Fibula Ribs Tibia Sternum Ulna Cranium Hyoid Metatarsals Xiphoid process Tarsals Pelvis Metacarpals Vocabulary Deciduous teeth Anterior Cementum Dentition patterns Periodontal Ligament Antemortem Postmortem Caucasoid Negroid Mongoloids Diaphysis Epiphysis Posterior Distal Proximal Crown Neck Root Enamel Dentin Pulp cavity Forensic anthropology Forensic odontology Male and Female Skeletal Remains “sexing” the skeletons is based on the skull, jaw, brow ridge, pelvis and femur. Determining sex is crucial when analyzing unidentified human remains. The forensic anthropologist can make determination of sex by comparing basic characteristics of certain bones. This of course is not always accurate but for the most part male bones are larger in size to female bones and are so because of the addition muscle that may build up on the male body through adolescence and into adulthood Male and Female Skeletal Remains: THE SKULL Skull has several key skull differences between male and females Male cranial mass is more blocky and massive compared to the females which are more rounder at the top Occipital protuberance (large projection on the back of head) is larger on males than female skull Mastoid process on the male skull is larger and rough compared to the female skull that has a smaller and smooth process The occipital bone on the male skull has muscle lines and protuberances marked, where female skull tends not to have muscle attachment lines. Zygomatic bone is more pronounced on the male skull. The female Zygomatic arch does not extend as a ridge posterior of the external auditory meatus, as the males does extend. Forehead/frontal bone.. / males slant back where female have a round forehead Male and Female Skeletal Remains: THE SKULL Male & Female Skeletal Remains: THE FACE The brow ridge (supercilary-ridge above eyes) on a skeleton can help determine gender. Females has less pronounced or non existent brow ridge. Males have a pronounced and larger brow ridges, Can also be described as females brow ridge margin is sharper, while males have a round and dull ridge margin. Refer to previous picture Male & Female Skeletal Remains: THE MANDIBLE Mandible is more rounded on the female skull creating a somewhat pointed chin where the male has a more squared shape. The female mandible measures an obtuse angle The male measures an acute angle. Refer to slide #10 Male & Female Skeletal Remains: THE PELVIS The pelvis or os pubis has important characteristics that help determine sex differentiation The pubic arch has a larger angle in the female than the male. Males have a narrower angle where the two pubic bones meet in front, measuring at 90 degrees or smaller Females have wider angle where the two pubic bones meet in front, measuring greater than 90 degrees. Females also have a wider pelvic opening. Males have a narrower, heart-shaped pelvic inlet Females have an open, circular pelvic inlet From an anterior view you will only see the coccyx bone, on the male from the same view you can see both the coccyx and the sacrum. Male & Female Skeletal Remains: THE PELVIS The pubic body is narrower in males than in the females Males usually do not have a ventral arc. The ventral arch is a bony ridge that is formed on the ventral (lower) side of the female os pubis. Female pelvic bone have a broader sciatic notch and raised auricular surface, where the male has a narrower sciatic notch and a flat auricular surface. Sacrum is straighter in the female and more curved in the males Acetabulum- the socket in the pelvis- is larger in males. Male & Female Skeletal Remains: THE FEMUR Femur The length of the femur is generally longer in the male skeleton. The diameter of the femoral head longer and bigger in the male skeleton. The oblique length of the trochanters is longer in the male skeleton Determining Ancestry There are three major anthropological racial groups based on observable skeletal features: Caucasoid, Negroid, and Mongoloids. It is important to note that there is more individual variation within races than there is general variation among races. With the increasing multiethnic and interracial society, many anthropologist do not feel confident making judgments concerning ethnicity/race of skeletal remains, but facial characteristics allow the examiner to narrow the field of identify. They eye socket (orbits), nasal bone, skull, teeth and chin are all examined. Caucasoid is a descriptor for people of European, Middle Eastern and East Indian descent. Eye sockets-oval orbits Nasal bone- long narrow nasal aperture (opening) Skull- narrow zygomatic arches and narrow mandible. Teeth-triangle palate Caucasoid Skull http://www.flickr.com/photos/396021 84@N02/3641970910/sizes/m/in/set -72157619878693631/ http://www.flickr.com/photos/396021 84@N02/3641970880/in/set72157619878693631/ http://www.flickr.com/photos/396021 84@N02/3641970842/in/set72157619878693631/ http://www.flickr.com/photos/396021 84@N02/3641162087/in/set72157619878693631/ Determining Ancestry Negroid is a descriptor for people of African, Aborigine, and Melanesian descent. Eye sockets-square orbits Nasal bone- wide nasal aperture Skull- pronounced zygomatic arch Teeth-Rectangle palate Long bones are longer and have less curvature and greater density. Negroid Skull http://www.flickr.com/photos/39602184@N02/3642241 944/in/set-72157619878693631/ http://www.flickr.com/photos/39602184@N02/3642241 916/in/set-72157619878693631/ Determining Ancestry Mongoloid is a descriptor for people of Asia, Native American, and Polynesian descent Eye sockets-rounded orbits Nasal bone- rounded nasal aperture Skull- wide zygomatic arches Teeth-Parabolic palate Pointed mandible Mongoloid Skull http://www.flickr.com/photos/39602184@N02/3747590 190/in/set-72157619878693631/ http://www.flickr.com/photos/39602184@N02/3642213 192/in/set-72157619878693631/ http://www.flickr.com/photos/39602184@N02/3642213 216/in/set-72157619878693631/ http://www.flickr.com/photos/39602184@N02/3641405 097/in/set-72157619878693631/ Long Bones Diaphysis: shaft of bone Epiphysis: ends of bone (long bones) Bones fuse in four stages Stage 1: Nonunion with no epiphysis (no growth plate yet) Stage 2: nonunion with separate epiphysis (growth plate formed but not attached) Stage 3: partial union of the epiphysis (growth plate is beginning to attach) Stage 4: complete union of the epiphysis (growth plate is completely attached and smooth) Determining Age Forensic anthropologist can estimate an individual’s age at the time of death by examining biological changes that occurred Age can be estimated by when teeth are erupting, bones are growing, and epiphyses (growth plates) are forming and uniting, and closure of cranial sutures in the skull. Between the ages of 25-30 years of age, age estimation becomes more difficult. All age estimates are given in an age range to avoid excluding possibilities. Fusing of Bone The stages of bones fusing occurs at different ages in different bones as well as different in males and females. There are general age determinations using epiphyseal union of the clavicle and iliac crest Clavicle: about 26 yrs. (males and females can differ – pg 281) Iliac Crest: around 20 yrs (pg 281) Estimating age based on cranial sutures can be done by examining the sutures. Saggital suture: 26 yrs males, 29 yrs females (complete & smooth) Coronal Suture: 35 + in males, 50+ in females (all 3 sutures) Lambodial suture: “” Determining age using the os pubis can be done be examining the symphysis pubis. HANDEDNESS Handedness: By examining both the right and the left of limb bones, it can be determined if a person was right or left-handed. The favoritism of one hand uses the muscles more on that limb, pulling on the periosteum and stimulating bone growth in thickness. Individuals overall build can be determined by the thickness of their bones and the characteristics of the bones at specific muscle attachment sites. This is due to the stimulation of the bone to thicken when stress is put on the periosteum. Repaired fractures can also be identified based on the growth of bone at the repair site. Region of the body Bone Age Arm Humerus bones in the head fused 4-6 Humerus bones in the head fused to shaft 18-20 Greater trochanter first appears 4 Lesser trochanter first appears 13-14 Condyles join shaft 20 Shoulder Clavicle and sternum close 18-24 Pelvis Pubis, ischium are almost completely united 7-8 Ileum, ischium, and pubic bones fully ossified 20-25 All segments of sacrum united 25-30 Lambdoidal suture close Begins 21 ends 30 Sagittal suture close 32 Coronal suture close 50 Leg (femur) Skull Injury & Disease Patterns of Bone Disease, injury and birth defects are also revealed in the bones Spina bifida Arthritis Fractures before and after death occurred Bones of a deceased person break differently compared to the bones of a live person Healing at the edge of a fracture indicates injuries occurred during life. Injury Patterns to Bone Cause of death Obvious Marks on skeleton Stab wounds Bullet holes Blows to the head Murder weapons can leave a distinctive mark and can be matched NAME AND NUMBER DECIDUOUS (BABY) AND PERMANENT TEETH A. Deciduous teeth - most dentists today use a modified version of the Universal Numbering System for children, with letters instead of teeth numbers. The primary teeth are designated by upper case letters A through T, with A being the patient's upper right second primary molar and T being the lower right second primary molar. NAME AND NUMBER DECIDUOUS (BABY) AND PERMANENT TEETH B. Permanent teeth - In the universal tooth numbering system, tooth number 1 is the patient's upper right third molar, on the right side of the mouth in the upper (maxillary) jaw. Numbering of teeth continues along the upper teeth toward the front and across to the last molar tooth back on the top left side (number 16). The tooth numbering continues by assigning teeth numbers descending to the lower left third molar (number 17) and follows the lower (mandibular) jaw up to the tooth farthest back on the bottom right side of the mouth (number 32). All teeth that should be there are numbered, including those teeth that have been removed for any reason or have not erupted yet (e.g. wisdom teeth). Total numbers of Teeth An adult has the potential to have the following total types of teeth: Incisors: 8 Canines: 4 Premolars: 8 Molars: 12 EMPLOY DENTITION PATTERNS AS A MEANS FOR BITE MARK IDENTIFICATION The diameter of the injury typically ranges from 25-40 mm. Often a central area of bruising can be seen within the marks from the teeth. This extravascular bleeding is caused by pressure from the teeth as they compress the tissue inward from the perimeter of the mark. EMPLOY DENTITION PATTERNS AS A MEANS FOR BITE MARK IDENTIFICATION Description of the Prototypical Human Bitemark A circular or oval (doughnut) (ring-shaped) patterned injury consisting of two opposing (facing) symmetrical, U-shaped arches separated at their bases by open spaces. Following the periphery of the arches are a series of individual abrasions, contusions and/or lacerations reflecting the size, shape, arrangement and distribution of the class characteristics of the contacting surfaces of the human dentition. Variations of the Prototypical Bitemark - Variations include additions, subtractions, and distortions EMPLOY DENTITION PATTERNS AS A MEANS FOR BITE MARK IDENTIFICATION Computer reconstruction of bite mark, 2003 Scientists from the Institute of Forensic Medicine collaborated with police in 2003 to solve a triple homicide. Three women were found beaten to death in an apartment outside of Zürich, Switzerland. One victim had a bite mark on her shoulder. After creating dental casts and using 3-D imaging technology to recreate the bite sequence, scientists were able to prove to a jury that the suspect made the mark. He was found guilty. Institute of Forensic Medicine, University of Bern http://www.bing.com/images/search?q=bite+mark+evid ence&form=QBIR&qs=AS&sk=&pq=bite+mark+evi&sp= 1&sc=113&adlt=strict#focal=46dee412a4aa0c1515c799929f6b 5bc6&furl=http%3A%2F%2Fwww.greggoldendds.com% 2Fimages%2Fshoulderali.jpg
