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Chapter 12: Human Remains “There is a brief but very informative biography of an individual contained within the skeleton, if you know how to read it…” —Clyde Snow, Forensic Anthropologist Human Remains Students will learn: How anthropologists can use bones to determine whether remains are human; to determine the gender, age, and sometimes race of an individual; to estimate height; and to determine when the death occurred Kendall/Hunt Publishing Company 1 Human Remains Students will be able to: Distinguish between a male and a female skeleton Give an age range after examining unknown remains Describe differences in skull features among the three major racial categories Estimate height by measuring long bones Describe livor mortis, rigor mortis, and algor mortis Kendall/Hunt Publishing Company 2 The Pathologist Determines the time of death. This can be done most accurately if the body is found within the first 24 hours of death Uses certain indicators such as algor, livor and rigor mortis. Kendall/Hunt Publishing Company 3 Algor Mortis Algor mortis is the cooling rate of the body after death. At a crime scene, the body temperature is obtained through: Rectal temperature Liver temperature Glaister equation: can be used from 1-36 hrs. (most accurate within the first 12 hrs. 98.4°F - internal temperature/1.5 = hours elapsed since death Generally the body cools 1 to 1 ½ degrees Fahrenheit per hour until it reaches the surrounding temperature Kendall/Hunt Publishing Company 4 Effects that Influence Algor Mortis Temperature of the surrounding environment Type of clothing on the body Wetness of the clothing Air movement Layers of clothing Size of the individual (smaller bodies cool faster) Kendall/Hunt Publishing Company 5 Livor Mortis Livor mortis is the settling of blood caused by gravity. It results in a reddish or purplish color pattern on the skin. Lividity can indicate the position of the body after death. There is no lividity in the areas touching the ground (capillaries are constricted; preventing blood pooling) Begins within a half hour after death. Kendall/Hunt Publishing Company 6 Livor Mortis When lividity becomes fixed, then the distribution of the pattern will not change even if the body’s position is altered. This helps determine if a body was moved after death. Lividity usually becomes fixed between 10 and 15 hours after death. Kendall/Hunt Publishing Company 7 Rigor Mortis Rigor mortis refers to the rigidity of the skeletal muscles after death First seen in the face, neck and jaw followed by larger muscles Noticeable stiffness occurs within 2-3 hours Effects begin to disappear in the same pattern (face first, followed by larger muscles) Gone within 30 hours, leaving the body limp. Kendall/Hunt Publishing Company 8 Rigor Mortis Temperature of body Stiffness of body Approximate Time Since Death •Warm •Not stiff •Not dead more than 3 hrs •Warm •Stiff •Dead between 3 and 8 hrs •Cold •Stiff •Dead 8 to 30 hours •Cold •Not stiff •Dead more than 30 hours Kendall/Hunt Publishing Company 9 Forensic Anthropology Forensic anthropology is a type of applied anthropology that specializes in the changes and variations in the human skeleton for the purpose of legal inquiry Kendall/Hunt Publishing Company 10 Forensic Anthropology A forensic anthropologist may provide basic identification information of skeletonized or badly decomposed remains. From a whole bone or part of a bone, the scientist may be able to determine: Human or animal Individual or mixed remains How long ago was death Was the body disturbed Cause of death An age range Sex Race Approximate height Diseases, or anomalies Kendall/Hunt Publishing Company 11 Osteology Study of bones 206 bones in an adult human Function of bones: Provides structure and rigidity Protects soft tissue and organs Serves as an attachment for muscles Produces blood cells Serves as a storage area for minerals Can detoxify the body by removing heavy metals and other foreign elements from the blood Kendall/Hunt Publishing Company 12 Bone Classification Bones are classified as: Long: longer than they are wide (arms, legs, hands and feet) Short: as long as they are wide (wrist and ankle) Flat: enclose soft organs (scapula, sternum, hip bone, rib and most skull bones) Irregular: odd shape (vertebrae and some skull bones) Kendall/Hunt Publishing Company 13 Estimation of Height The height of a person can be calculated by using the length of certain long bones, including the femur, tibia, humerus, and radius. Below are the equations to determine average measurements for both male and female. (All measurements are in centimeters and accurate to within +/-7.5 cm) Male Female femur x 2.23 + 69.08 tibia x 2.39 + 81.68 humerus x 2.97 + 73.57 radius x 3.65 + 80.40 femur x 2.21 +61.41 tibia x 2.53 + 72.57 humerus x 3.14 + 64.97 radius x 3.87 + 73.50 Kendall/Hunt Publishing Company 14 Gender Differences in Bones os pubus = pubic bone Females: in general have smaller bones; straight sacrum; os pubis has a ventral arc, a wide pubic body, and a large pubic arch angle. Males: in general have larger bones with larger surface area for muscle attachment; curved sacrum; os pubis has a no ventral arc, a narrow pubic body, and a short pubic arch angle. Kendall/Hunt Publishing Company 15 Gender Differences in Bones The entire pelvis of females is also different from males. The subpubic angle, and the space in the middle of the pelvic bone is wider to make birthing easier. Kendall/Hunt Publishing Company 16 Male Female Sub Pubic Angle Now you try… Identify which is male and which is female female male Kendall/Hunt Publishing Company 18 Gender Differences The ribcage and shoulders of males are generally wider and larger than that of females. In addition, about one person in twenty has an extra rib. This is more common in males than in females. Kendall/Hunt Publishing Company 19 Gender Differences In males the index finger is sometimes shorter than the third finger. In females, the index finger is sometimes longer than the third finger. This is not often used as an indicator of gender as there are many exceptions. Is this a male or female hand according to the above rule? Kendall/Hunt Publishing Company 20 Gender Differences in Skulls A. Cranial mass: blocky and massive in men; rounded and tapered in women B. Temporal ridge: more prominent in men C. Zygomatic arch: wider and more pronounced in men D. Mandible: large, square in men; small, round in women E. Deeper cranial mass in men with sloping forehead F. Brow ridge: more pronounced in men G. Larger teeth in men Kendall/Hunt Publishing Company 21 Now you try… Identify which is male and which is female female Kendall/Hunt Publishing Company male 22 Age Determination Most accurate estimations from: Teeth Epiphyses or growth plates Pubic symphysis Cranial sutures: the three major cranial sutures appear as distinct lines in youth and gradually close from the inside out. Investigators always use an age range because of the variation in people and how they age. The investigator does not want to eliminate any possibilities for identification. Kendall/Hunt Publishing Company 23 Age Determination Using Epiphysis The dyphsis —shaft of a long bone: makes up most of the length Epiphyses —growth plates at both ends of the long bone: they fuse to the bone during adolescence Bones commonly used for this type of age determination are the medial clavicle (collar bone; its medial ends meet in the center of the body); and the iliac crest (top) of the hip bone There are four stages used to estimate age: They are simply referred to as Stages 1,2,3, and 4 and are outline on the next two charts. Kendall/Hunt Publishing Company 24 Age Determination Using Epiphysis Stage of Union of Medial Clavicle Male Female Non-union without separate epiphysis (no growth plate yet) 21 or younger 20 or younger Non-union with separate epiphysis (growth plate is formed but not attached) 16-21 17-20 Partial union (growth plate is beginning to attach to the bone) 17-30 17-33 Complete union (growth plate is attached and smooth) 21 or older 20 or older Kendall/Hunt Publishing Company 25 Age Determination Using Epiphysis Stage of Union of the Iliac Crest Male Female 16 or younger 11 or younger Non-union with separate epiphysis (growth plate is formed but not attached) 13-19 14-15 Partial union (growth plate is beginning to attach to bone) 14-23 14-23 17 or older 18 or older Non-union without separate epiphysis (no growth plate yet) Complete union (growth plate is attached and smooth) Kendall/Hunt Publishing Company 26 Cranial Sutures Sutures —serrated, interlocking joints on skull. Allow for growth: fuse together as humans age. Three major sutures: Sagittal suture—top of skull; divides right from left; runs from top to middle of back Coronal suture—from temporal across top; side to side Lambdoid suture—back of skull Kendall/Hunt Publishing Company 27 Age Determination Using Cranial Sutures Sagittal suture Sagittal suture completely closed Males—26 or older Female—29 or older Sagittal suture is completely open Male—less than 32 Female—less than 35 Complete closure of all three major sutures Male—over 35 Female—over 50 Lambodial Kendall/Hunt Publishing Company Coronal 28 Age Determination Using Basilar Suture Basilar Suture Technically known as the synchondrosis sphenooccipitalis, closes in females as young as 14 and in males as young as 16. If the suture is open, the individual is generally considered 18 or younger. Kendall/Hunt Publishing Company 29 Race Race is difficult to determine from most skeletal remains, especially since pure races are becoming uncommon. An experienced forensic anthropologist can generally place skulls into one of three groups: Caucasoid—European, Middle Eastern, and Indian descent Negroid—African, Aborigine, and Melanesian descent Mongoloid—Asian, Native American and Polynesian descent Kendall/Hunt Publishing Company 30 Race Characteristics Caucasoids—have a long, narrow nasal aperture, a triangular palate, oval orbits, narrow zygomatic arches and narrow mandibles. Negroids—have a wide nasal aperture, a rectangular palate, square orbits, and more pronounced zygomatic arches. The long bones are longer, have less curvature and greater density. Mongoloids—have a more rounded nasal aperture, a parabolic palate, rounded orbits, wide zygomatic arches and more pointed mandibles. Kendall/Hunt Publishing Company 31 What differences do you notice between these three skulls? Can you determine race? Caucasoid Negroid Kendall/Hunt Publishing Company Mongoloid 32 Odontology and Identification Teeth are often used for body identification because: They are the hardest substances in the body They are unique to the individual X-rays are a good record of teeth Kendall/Hunt Publishing Company 33 Odontology The identity of an individual can be determined by comparing a person’s teeth to their dental records. Unusual features including the number and types of teeth and fillings, the spacing of the teeth, and/or special dental work (bridges, false teeth, root canals) help to make a positive identification. Kendall/Hunt Publishing Company 34 Facial Restoration After determining the sex, age, and race of an individual, facial features can be built upon a skull to assist in identification. Erasers are used to make tissue depths at various points on the skull. Clay is used to build around these markers and facial features are molded. Kendall/Hunt Publishing Company 35 Steps in Facial Reconstruction With a skull: Establish age, sex and race Plot landmarks for tissue thickness Plot origin and insertion points for muscles Plot landmarks for facial features Select a dataset and mount markers for tissue thickness Mount the eyes Model muscles on skull Add fatty tissue around eyes and lacrimal glands Add eyelids Add the nose Add the parotid gland Add the ears Cover all with layers of skin Detail the face Kendall/Hunt Publishing Company 36 One Final Product John List killed his entire family, moved to a new town and assumed a new identity. Seventeen years later, Frank Bender reconstructed what he believed List would look like. It was shown on America’s Most Wanted, and he was turned in by the viewers almost immediately. . . looking very much like the reconstruction. Check out more about this story on CourtTV’s crime library: www.crimelibrary.com/notorious_murders/family/list/1.html Kendall/Hunt Publishing Company 37 People in the News Bill Bass is a forensic anthropologist who has assisted law enforcement with hundreds of cases. He established the world’s first and only laboratory devoted to the study of human decomposition at the University of Tennessee’s Anthropology Research Facility. It is known as “the body farm.” Kendall/Hunt Publishing Company 38 The Body Farm The nickname of a two and a half acre research facility in Tennessee developed in 1980 by Bill Bass where bodies are placed in various conditions and allowed to decompose. Its main purpose is to observe and understand the processes and timetable of postmortem decay. Over the years it has helped to improve the ability to determine "time since death" in murder cases. Hic locus est ubi mortui viveuntes docent. This is the place where the dead teach the living. Kendall/Hunt Publishing Company 39 Anthropologist at Work This anthropologist is hard at work dusting away material from these imbedded bones. Picture taken at Chicago’s Museum of Natural History Kendall/Hunt Publishing Company 40 More Applications Forensic experts may be called upon to give information on the life and death of humans and animals in unique circumstances, including: Mass Murder (Oklahoma bombing, plane crashes, World Trade) Earlier man (mummies, Iceman, Lindow man) Historical Significance (Holocaust, uncertain death of famous people) Prehistoric Animals (Dinosaurs) Kendall/Hunt Publishing Company 41 Animal Facial Restoration Determining what T Rex looked like using the bone formation. From this: To this: Kendall/Hunt Publishing Company 42 More Information For additional information on Bill Bass and the Body Farm www.crimelibrary.com/criminal_mind/forensics/bill_bass/4.html On forensic artists: http://origin-www.crimelibrary.com/criminal_mind/forensics/art/1.html Kendall/Hunt Publishing Company 43