Anthro 360 Exam 1 SG - Test 1 review PDF

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+What types of instruments do forensic (and physical) anthropologists use? -OSTEOMETRIC BOARD -SLIDING CALIPER -SPREADING CALIPER +Is it Bone? Know the characteristics of bone. - Bone when magnified will reveal a fairly compact surface with some graininess - Bone is the strongest biological material in existence, extremely light weight - Composite material-protein and mineral - A living tissue that can repair and reshape itself throughout life - Produces blood cells - Wolff’s Law: bone is laid down where needed and resorbed where not needed. +How many bones are there in a human skeleton? Adult human skeleton =

206 bones

Subadult human skeleton = Many ossification centers Cardinal direction (Superior, inferior, lateral, posterior) (Long Bones-proximal, distal) Superior (cranial): Up; point or region lying above another point or region (top) Inferior (caudal): Down; point or region lying below another point or region (bottom) Lateral: Point or region lying away from the midline of the body medial: point or region lying closest to midline of body anterior: front of the body Posterior (dorsal): Back; point or region lying closest to the back of the body Proximal: Point closest to an articular point with the body Distal: point fartherst away to an articular point with the body FRONTAL Frontal: Forehead bone that comprises the front part of the braincase and the upper part of the eye orbits supraorbital tori: thickened areas above each eye orbit (found in some skulls, mostly males) Glabella: Skin between the eyebrows and above the nose. most anterior point on the frontal on the midline; located between supraorbital when present -Nasals -nose -Zygomatic Zygomatic bones compose the lateral walls of the eye orbits (also known as the cheek bones) -Maxilla form the floor of the eye orbits (upper jaw)

-Temporal (features:external auditory meatus, mastoid process) temporal: forms the lower part of the sides of the braincase (your temples) external auditory meatus: the paired bones that make the ear opening (ear canal) mastoid process: area behind your ear -Parietals these bones paired make up the middle of the braincase -Occipital (features:occipital condyles, foramen magnum, nuchal crest) occipital condyles- a protrusion on the occipital bone of the skull that forms a joint with the first cervical vertebra,enabling the head to move relative to the neck. -foramen magnum: large opening at the base of the skull forming the passage from the cranial cavity to the spinal canal. -nuchal crest-is where the neck muscles attach to the skull. It's a rough ridge on the occipital bone. -Mandible (features:mental eminence) Mandible: lower jaw mental eminence: The mental eminence is basically the chin. Anatomists call this the mental eminence because people sometimes hold it when they think. It is often larger and squarer in males than in females. +Bones of the Post-Crania: Appendicular Skeleton *Upper Limbs -Clavicle Clavicle (collarbone): is S-shaped when viewed from above or below -Scapula triangular shoulder blade -Humerus (what type of joint?): upper arm bone; synovial ball & socket joint (glenohumeral joint) -Ulna: forearm bone, (pinky side) -Radius: forearm bone, (thumb side) Lower Limbs -Os Coxa: hip bone (Features: Iliac crest, greater sciatic notch, ischial tuberosity, acetabulum, pubic symphysis) -iliac crest: The iliac crest is the curved superior border of the ilium, the largest of the three bones that merge to form the os coxa, or hip bone. When you place your hands on your hips the skin above the iliac crest is what they rest their hands on. -greater sciatic notch: a notch on the posterior border of the hip bone between the posterior inferior iliac spine and the spine of the ischium. -ischial tuberosity: a swollen part or broadening of the bone in the frontal portion of the ischium, the lowest of the three major bones that make up each half of the pelvis. As the point of fusion of the ischium and the pubis, it is attached to various muscles and supports the weight of the body when one is sitting. -acetabulum: the socket of the hipbone, into which the head of the femur fits.

-pubic symphysis: A firm anterior fibrocartilaginous joint between the two pubic bones, which loosens during late pregnancy and delivery to facilitate the passage of a baby.

-What three bones make up the os coxa and fuse together to make a single bone during development? -the ilium, ischium, and pubis -Femur (What type of joint?): thigh bone -ball and socket. (synovial) Patella: knee cap -Tibia: shin bone -Fibula+ Calf Bone

Dentition- what is the human dental pattern?

-Incisors 2 sets -Canine 1 set -Premolars 2 sets -Molars 3 sets Apex of the root is the last part of the tooth that develops Directions: Mesial, distal, occlusal, lingual, buccal mesial: parts of the teeth that are closest to the midline distal(i.e distant=away): surfaces away from the midline. occlusal: chewing surface of the teeth lingual (i,e speaking, tongue): inner parts of the teeth (towards the tongue) buccal: outer parts of teeth (near the cheeks) labial(i.e labia means lips): parts of the teeth that are closest to the lips Text-anatomy of a bone. What is the difference between trabecular and cortical bone? -TRABECULAR : spongelike structure that occurs in the metaphyses of long bones, within the ribs and all bones of the hands and feet, inside the bodies of the vertebrae, and in between the inner and outer cortical surfaces of the cranial vault. Primary function is to reinforce the bones without adding excess weight. -CORTICAL : the smooth exterior of all skeletal elements. Composed of strong, wellorganized tissue called lamellar bone that is laid down in thin layers that run parallel to the long axis of a bone.

+Is it human? -Non human cases are often ¼ to ⅓ of cases -easy way to determine: we are bipedal (look at morphology)

-THORAX (quadra-pedal morphology) scapulae are elongated and dorsally placed pelvic girdle is elongated and more narrow ribs are less curved at the neck human pelvises are “bowl shaped”, we are more flexible, and are “barrel chested” -Gross Differences (morphology) articular (joint) surfaces and epiphyseal surfaces are larger, more sculpted on NON-humans areas of muscle attachment are more robust and rougher on non humans. -Long bones shafts are straighter and less rugged in human non-human: distal and proximal ends are more sculpted tibia and fibula are articulated in some species less rugged = less muscle mass.

Long bones are hard, dense bones that provide strength, structure, and mobility. The femur (thigh bone) is a long bone. A long bone has a shaft and two ends. There are also bones in the fingers that are classified as "long bones," even though they are short in length -Cranium in nonhumans more robust and developed, small cranial capacity, no post orbital bar, snout exception: immature animal fragments may appear similar. -little critters and human infant bones are often mistaken for one another -Thickness of compact bone in relation to total bone diameter human: ¼ thickness of total diameter mammal: ⅓ thickness bird: ⅛ thickness -Dentition less generalized than human’s and is recognizably different. the only similarity in our dentition is with pigs. -Environment is an important non-morphological variable that can aid in identification of species. +Contemporary vs. non-contemporary -What rules can we follow to narrow down whether or not a burial is contemporary vs. non contemporary? Does contemporary mean forensic?

-To be contemporary the body must be < 50 years deceased. 1.

Position of body in ground fetal position, bundle burial, ossuaries (mass burials) usually= 1.1. archaeological 1.2. extended burial- note the position of hands and feet and artifacts 1.3. construction? usually archeological 1.4. personal objects can help age an individual- medical implants, levi jeans, glasses, ect.

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Surface finds note location and parts present and missing 2.1. 2.2. note condition of bone 3. Knowledge of local history wars/battles fought in area 3.1. 3.2. Native American occupation 3.3. unmarked family plots 3.4. other groups which may have not recorded cemetery/burial information (slave cemeteries) 4. State of Preservation NON-contemporary traits- discolored, grainy, dry, light in weight, often 4.1. fragmented, fragile, and completely devoid of any soft tissue present during life 4.2. contemporary traits- off-white color, smooth, greasy, heavy, solid, and usually containing some soft tissue. 5. Body modifications 5.1. human remains with cranial flattening and tooth filing are probably noncontemporary (too old) 5.2. remains that have amalgams, crowns, and bridges should be considered contemporary 6. Contemporary does NOT equal forensic 6.1. trophy skulls, biological supply specimens, cadaver specimens, religion based material, cemetery remains. In terms of bone itself: -What is the texture? 1. Contemporary bones have a smooth surface comparable to ivory 2. Bones that are exposed to different climate factors causes the surface to erode from soil acids a. this causes the loss of the original smoothness 3. Grainy or pitted bones means that it has been a considerable amount of time since the time of death a. Individuals who are older typically have more graininess i. 60+ years old: loss of smoothness to the cortical bone which is smooth in the young b. Diseases can cause bone loss which affects the overall texture of the bone i. seen as raised striations along the long axis of long bones ii. pitting due to anemic conditions of the individual -What is the weight? 1. When bone first comes out of the body it has a significant amount of weight due to fats and fluids 2. Weight decreases due to the moisture evaporating (calcium salts, and fluids) a. further decrease in weight due to decalcification i. loss of calcium and other minerals b. occurs with long removal from the body and an extended burial time

3. Weight and Age have an inverse relationship a. accumulation of minerals in buried remains b. groundwater can also cause bone to gain weight due to the water depositing minerals into the bones i. groundwater can also cause decalcification i-What is the color? 1. Yellowish- white to yellowish-brown tint when inside of body due to saturation of body fats and fluids 2. Becomes ivory in color after the removal of soft tissue and dehydration a. in strong sunlight it becomes white then gray after a few years b. buried bone will take on a brown color of the surrounding soil c. prehistoric burials have been known to cover the buried body with red ochre, causing the bones to have a red tint 3. Discoloration is more indicative of age -Fragmented or whole? 1. Contemporary bones are generally whole with little fragmentation a. excessive crushing is due to injuries from accidents involving aircraft and trains 2. time and rough handling causes bones to become broken and sometimes highly fragmented a. some may be composed of many fragments b. bones buried from ancient times are fragmented to a degree that is not normal to fresh bones i. can be used to determine age SEARCH AND RECOVERY -Location of Remains -finding a disturbance in the environment does not equal a grave -What to look for from the surface Bare spot surrounded by growth, “grazed” surface, mound, or sunken area. Longer period of time: Re-growth of area not consistent with previous foliage. Arid environments will take years to recognize Short roots stand out.

-Stratigraphy of a grave DISTURBANCES TO SOIL FROM DIGGING A HOLE Test pit for stratigraphy change Organic layers that were on on top all jumbled/mixed up -Perimeters of a crime scene (what are they)

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inner core area: where evidence is concentrated crime scene perimeter: potential area for crime outer perimeter: barrier for press and public

-What are these techniques? What is the procedure? After crime scene has been established: 1. systematically survey the area 1.1. Reading the land- follow scavenger paths, check downhill, check downstream, check rat nests, bird nests and other collections of vegetation. 2. flag surface finds 3. photograph the area including identifiable markers and scales 4. remove excess vegetation 5. establish a grid system 5.1. plot surface finds, include outline of grave, position of body, etc. 6. once thorough documentation has taken place, mapping, photographs, all IN SITU (in its original place) then recovery takes place 6.1. inventory, excavate slowly, pedestal, exposure burial before removing anything, careful archaeological techniques may reveal essential info and trace evidence. 6.2. soil samples- aid in time since death, take samples of insects that may have been present, continue excavation below the remains, screen ALL soil for further evidence and missed items.

DECAY & DECOMPOSITION Stages of Decomposition and Environments that may affect it ●

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Fresh (Usually conducted by the pathologist), (Based on livor mortis (settling of blood, whitens upper areas of body, appears couple hours after death and reaches maximum in 8-12 hrs), rigor mortis (stiffening of body, body runs out of ATP, usually 2-4 hrs after death, peaks at 10-12 hrs then subsides, hastened by fever, convulsions, or extreme activity) , and body cooling (1.5 degrees F per hour loss) Early decomposition - stage 1 (Bloating): production of methane, body acquires greenish tint, bloating most pronounced in abdomen, expansion of face, arms, legs, and scrotum, displacement of arms, displacement of clothing. Early decomposition - stage 2 (Post-bloat)- Bloating released, Sagging of flesh, Autolysis. Skin slippage, greenish discoloration, hair slippage. Advanced decomposition- beginning skeletal exposure, runoff of bodily fluids -- 3 months at 1 foot = 1 year at 4 feet Mummification- when loss of moisture is rapid, deters insect invasion, some

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insects may attack undersides (forms a “tent” over body), mummified remains can be preserved for centuries. Desiccation- is the state of extreme dryness, or the process of extreme drying. Skeletonization- exposure of most of the skeletal elements, may occur in both dry and moist environments, bones may stay in this state for many years. Skeletal decomposition- sun bleaching, fluctuations in moist and dry environments, abrasion from movement, root etching and fungal invasions.

Side Note: Adipocere is a greyish-white “cheesy” substance - Hydrolyzed fat - Can remain for years once formed - Common in prolonged exposure to wet or moist conditions

-Environments that may affect decomposition: -Ambient temperature - Air movement -Insect infestation - Carnivore activity -Humidity - Rodent activity -Rainfall - Size and weight of body -Soil pH - Substrate -Trauma - Clothing or covering -Depth of burial - Embalming - Freezing...