Anthro Midterm PDF

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Forensic Anthropology Midterm

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Evidence of trephination (cranial surgery) or other ancient medical practices are indicative of a non-contemporary origin

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Sometimes burials are disturbed when construction is done and forensic anthropologists are called to see if the remains are contemporary or not

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Discovery of non-contemporary remains is the accidental uncovering of historic cemetery burials that have lose their grave markers (construction/roadwork) ○

These remains are not considered medicolegally significant, as the individual's death would have been investigated previously and the individual already identified

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Therefore, these discovered are concerned w/ re-associating the remains to the burial plot/potentially contacting any living relatives depending on the date of the burial

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“Bomb curve” radiocarbon method is used to date human remains ○

Can provide valuable data and may become practical in the future of forensic death investigation

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At death, organisms stop taking in carbon, and the C14 begins radioactive decay

Best-established methods are those relating to artificial radiocarbon dating w/ special reference to the modern bomb curve

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Analysis of radiocarbon values in bones and teeth can distinguish whether an individual died before or after 1950. ○

Recent radiocarbon studies of human teeth indicate that they can be used to estimate the date of birth of an unidentified decedent using the bomb curve

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Combined w/ standard age at death estimation methods, radiocarbon dating utilizing the bomb curve may hold significant promise for facilitating identification as well as determining contemporaneity.

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Forensic anthropologists can often make the determination of medicolegal significance, especially between human and non-human bones, on the basis of high quality photographs that include a scale ○

In this manner, anthropologists can provide real-time or expedient answers even if they cannot be present at the scene

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Specimens determined not to be of medicolegal significance may be returned to investigators, curated as comparative material, or discarded depending on the policies and needs of the investigators and forensic anthropology laboratory

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Such items should be collected and removed from the scene and not left in place to be inadvertently rediscovered at a later time

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The recognition of the medicolegal significance of material to a forensic anthropologist includes determining whether the material is skeletal versus some other material, whether skeletal material is human or non-human, and whether human skeletal material is contemporary or non-contemporary.

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The determination of skeletal or non-skeletal origin is typically accomplished by gross visual examination, but when material is small and/or taphonomically compromised, this may be accomplished by using radiography, microscopy, or elemental analysis.

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A recently developed method of elemental analysis for determining skeletal or non-skeletal origin involves the use of X-ray fluorescence spectrometry (XRF) to determine the presence of calcium and phosphorus. The approach is reliable and non-destructive.

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Differences between human and non-human skeletal remains are primarily differences in architecture (shape) as a result of differences in locomotion (bipedalism versus quadrupedalism).

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The determination of human or non-human origin is typically accomplished by gross visual examination, but other techniques that may be employed include histology or protein-based methods such as protein radioimmunoassay (pRIA).

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The determination of contemporary or non-contemporary is typically based on observations of taphonomy, context, and biocultural information. Radiocarbon dating may also be useful.

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Artifacts are an example of contextual information that may provide clues regarding whether remains are contemporary or non-contemporary. Artifacts include personal effects (items belonging to the deceased individual) and grave goods (items deposited with the deceased individual by other persons). Chapter 6: Forensic Archaeology

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Forensic archaeology is the application of archaeological theory and methods to the resolution of medicolegal and humanitarian issues ○

It may include methods involved in searching for, locating, surveying, sampling, recording and interpreting evidence as well as the recovery and documentation of human remains and associated evidence

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They are normally requested to assist investigators and law enforcement in assessing the applicability of remote sensing techniques, developing recovering strategies, mapping recovery scenes, dating evidence, and reconstructing events/

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It was long believed that outdoor contexts too quickly degraded evidence

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Archaeology and physical anthropology are subfields of anthropology ○

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So forensic anthropologists are trained in both skeletal analysis/archaeological methods

The purpose of forensic archaeology is to properly investigate a recovery scene from the beginning of a search to the removal and transport of the evidence from the scene and to maintain context and the chain of custody for all evidentiary materials recovered

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Location where human remains are found is often called a scene or recovery scene

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Outdoor scenes involve remind that are on the surface, buried, submerged, involved in fires

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Surface scenes occur when remains are deposited on the surface of the ground

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For remains that have decomposed to the point of skeletonization scavenging and other natural and physical forces contribute to the scattering of remains from their initial deposition site ○

Remains that have been redistributed in this manner are referred to as surface scatter

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Burial scenes involve remains that are interred or deliberately buried underground in a grave

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Fire scenes are those involving thermally altered remains, which are often other burned debris (building materials or plant debris)

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Forensic archaeology methods are typically applied to the outdoor location and recovery of remains including surface remains and burials, usually when substantial decomposition or fragmentation has occurred ○

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Principles can be applied to indoor scenes too as well as under water and fire scenes

When remains and evidence are collected and removed from the scene, the context is permanently altered and the spatial relationships are lost

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Most modern crime scene processing approaches are now based largely on principles developed in the field of archeology

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The main principles of archaeology are the understanding of temporal and spatial relationships which are exemplified in steno’s law, and which form the basis of the interpretation of context through the understanding of stratigraphy and relative positioning

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There are four recognized phases of archaeological investigation ○

1- systematic search: the search phase involves locating areas that may warrant further investigation. This primarily involved surface survey, often by walking transects and noting archaeological features: remote survey using maps and aerial photography is also common. It involves search for hi,an remains, usually in a burial feature or surface remains

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2- evałuation of an area for significance: once a potential area for interest is located or identified, the area is evaluated to determine whether additional investigation is required.

This phase involves subsurface survey in order to determine site boundaries and focal areas. This phase is performed in order to evaluate whether an area of interest warrants full scale excavation, such as if a construction project during which ancient human remains were uncovered needs to be halted to permit a large scale archaeological excavation. The evaluation phase is typically brief and straightforward in forensic scenarios such as an isolated burial or surface scatter because the area of interest is rather small and can be investigated relatively quickly without significantly disturbing the scene. Plane crash; scenes can be quite large ○

3- Recovery: systematic recovery and preservation of the material of interest from the scene. In an archaeological context, this phase involves the excavation of an archaeological site, feature, or structure and collection of associated artifacts and ecofacts in order to gain information about a culture through the materials they left behind.

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4- Interpretation and reporting: generation of a report and interpretations based on the activities and products of the previous three phases. Phase IV reporting should be accompanied by a map of the project area as well as interpretations and conclusions. In an archaeological context where sites may be investigated slowly over the course of many years, Phase IV reports are often completed annually, providing a summary of past work, detailing the current progress, discussing all findings to date, and making justifications and recommendations for the next year’s work. Even if a search did not result in the location of remains, the report should document the procedures used as well as the area that was searched

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Detection of a scene involves the search for and location of remains

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Methods differ, for example, when searching for surface remains versus buried or submerged remains, and different approaches may be required in steep, dense terrain versus an open field.

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The most common search technique for outdoor scenes of virtually any type is the pedestrian survey or line search (see Figure 6.1). A line search is performed by having a number of search personnel form a straight line at one end of the search area. This often includes a forensic anthropologist or archaeologist as well as a team of law enforcement personnel and other specialists at the scene ○

Each person should carry pin flags to mark areas of interest

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Additional searches are often conducted after the first search; for example, a walking line search may be conducted to locate the remains, followed by a similar search on hands and knees in order to allow the searchers a better view of small details on the ground

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A line search should have a “line leader” who keeps the pace and direction of the line as it progresses through an area of interest, ensuring that the search occurs systematically. Often, the forensic anthropologist will follow behind the search, evaluating flagged items for forensic significance

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In addition to the remains themselves, other relevant evidence may also be discovered that is associated with the scene, such as animal dragging trails or maggot trails, rodent burrows/nests, and artifacts such as clothing or jewelry. It is also important to visually scan the rest of the search area above ground, including up in trees. Birds will often take hair from remains to be incorporated into their nests.

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Buried bodies will often be associated with a soil depression, differential vegetation growth due to the disturbance of living plants when digging or changing of the soil from body decomposition, or abnormal accumulation of tree branches or other forest debris from perpetrators attempting to cover the disturbed area. Other soil disturbances associated with burials may include variation in soil color, cracks, soil mixing, and leftover dirt (back-dirt  ) ○

When a grave is dug, the horizons are disturbed, and soils from the different horizons are mixed together. The new soil mixture that's placed back into the grave will typically differ in color and quality

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Once a body is placed into the grave, all of the soil will not fit back into the hole. This will result in left over dirt that can usually be found in a mound over the grave, or as a back-dirt pile near the grave.

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As the body decomposes and the infill settles and becomes more compact, a depression will usually form over the grave site.

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In cases of buried bodies, probing the soil may release the odors of decomposition to the surface and allow the cadaver dog to detect the odor more easily. Various factors can affect the reliability and effectiveness of cadaver dogs in remains searches. For example, weather conditions may affect the ability of a cadaver dog to locate the source of the odor, or a large number of people at a scene may distract the animal.

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The recovery of buried remains typically involves excavation  , or the exposure and recovery of the remains through a slow and careful digging process. This usually involves small hand tools including trowels and brushes

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Once the remains have been removed from the grave, a metal detector should be used on the grave floor to search for additional evidence such as bullets, coins, or jewelry still obscured by soil

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In fatal fire scenes, documentation of the position of the body and its relationship to other features is important in the interpretation of the thermal alteration pattern of the remains during later lab analysis. In any of the scene types, after collection of the visible remains, the recovery area should be excavated somewhat below the surface (usually at least 10 cm) to look for remains or other evidence that may have settled into the soil or foundation material.

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Scene documentation should include detailed written notes, and ample photographs of the overall scene, midrange views, and close-ups of the material recovered. Videography or laser scanning may also provide good overviews of the scene and the approaches used.

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Triangulation is the process of determining the location of a point (here, the piece of evidence such as a bone) by measuring the angles to that point from a line between two known points

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Skeletal remains should generally be packaged in paper bags or other breathable material. This will prevent the growth of mold, which can occur if damp skeletal remains are packaged in materials such as sealed plastic bags. Mold on skeletal remains can obscure and stain surface features used in anthropological analyses, and can also complicate DNA analyses. If bones are wet, they should be allowed to dry prior to packaging.

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Plastic or other non-permeable packaging may be appropriate for skeletal material with a significant amount of adhering soft tissue, but they should be unpackaged and processed once they arrive at the medicolegal authority’s office or forensic laboratory. Paper packaging will also offer some protection to the skeletal material during transport, preventing breakage or fracture from bones contacting one another.

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Additional packaging and protection measures may need to be considered in certain circumstances, such as if the materials will be transported a long distance or mailed, or if the remains are thermally altered. Burned bones are often very fragile and the slightest movement may cause additional fragmentation. One approach is to carefully wrap foil around individual bones which can keep any subsequently formed bone fragments in relative anatomical position. Cotton, gauze, or other soft packaging may also help prevent further damage.

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In 2008, a sheriff-coroner’s office in Northern California requested the services of a forensic anthropology team to aid in the excavation of a clandestine grave. Acting on information from an associate of an already convicted suspect, the sheriff’s office identified what they believed to be a grave site. Each forensic anthropology team member was assigned a specific role, such as photography, excavating, mapping, screening, documentation, evidence collection, and metal detection. The suspect had already been convicted and sentenced for homicide in the absence of the victim’s body, but the case was under appeal and it became essential to locate the victim’s

remains and reconstruct the circumstances surrounding death. The grave outline was located by using trowels to scrape the surface and identify differences in soil color and texture. ●

Forensic archaeology is the application of archaeological theory and methods to medicolegal cases, including searching for, locating, surveying, sampling, recording, and interpreting evidence, as well as the recovery and documentation of human remains and associated evidence

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A location where remains are found is called a scene or recovery scene. Common sense types include surface, burial, submerged, fire, and mass fatality.

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Similarly to excavating an archaeological site, processing a scene is inherently destructive, permanently altering the context. Documentation and preservation of contextual information is therefore critically important.

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Methods of locating a scene may include line searches, subsurface probing, thermal imaging, geophysical techniques, or cadaver dogs. Each has limitations, and certain approaches may only be appropriate in certain situations.

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The recovery process typically involves denuding the scene, establishing a datum, screening, excavation, and collection.

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Scenes can be mapped using a variety of approaches including triangulation,trilateration, azimuth, baseline, and grid. Specialized mapping approaches such as a total station and GPS may also be employed. After collection, remains should be packaged in a way that preserves the quality of the evidence. Skeletal remains should generally be packaged in paper bags or other breathable material that is marked with the date and location of the recovery, the person who packaged or recovered the evidence, and a case identification number.

Chapter 8: Estimating Sex ●

Estimating sex from skeletal remains involves the identification and evaluation of characteristics that tend to show differences between male and female skeletons, which are variably expressed throughout the skeleton

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These differences are primarily related to size and architecture which result from different biomechanical functions of joints for efficiency in locomotion (movement, usually walking) and parturition (childbirth).

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The ability to differentiate between male and female skeletons is due to sexual dimorphism, or the expression of phenotypic differences between males and females of the same species. Sexual dimorphism usually relates primarily to differences in morphology (size and shape), but may also

refer to differences in physiology and behavior. In forensic anthropology, morphological differences between males and females are the most useful for sex estimation. ○

In comparison to other animals, humans display relatively little sexual dimorphism, humans display little sexual dimorphism

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For example, many bird species differ significantly in color and ornamentation. Additionally, many male and female non-human primates including gorillas differ greatly in size. Humans, on the other hand, sh...