Thesis (M.A.)--Texas State University--San Marcos, 2010. / Vita. Appendices: leaves 59-98. Includes bibliographical references (leaves 99-104).

Shark attacks on humans are increasing every year, and due to this fact, it is important to understand the damage that these predators can inflict on bone. The present study examined the striation patterns that shark teeth leave behind on bones during an attack or scavenging event and determined whether they can be used to identify the species of shark involved. The present study examined twelve different species of sharks including white shark (Carcharodon carcharias), tiger shark (Galeocerdo cuvier), and bull shark (Carcharhinus leucas), as there are high incidences of attacks reported of these species. Striations were made in dental wax using the teeth of these species, as well as nine others including blue shark (Prionace glauca), tawny nurse shark (Nebrius ferrugineus), blacktip reef shark (Carcharhinus melanopterus), dusky shark (Carcharhinus obscurus), java shark (Carcharhinus amboinensis), gray reef shark (Carcharhinus amblyrhynchos), sand tiger shark (Carcharias taurus), cookiecutter shark (Isistius brasiliensis), and lemon shark (Negaprion brevirostris), to compare morphologies, their serration patterns, and what striations would be left on bone. It was hypothesized that the striations left in the impressions would be distinct to each species and would provide another method to identify species implicated in attack and scavenging events on humans. The results of this study suggest a statistically significant difference between the patterns of serrations found between some species of sharks examined. The white shark and the tiger shark can be distinguished from the other species in the present study. Further research on this method should be conducted, so future scientists can identify species involved in predation events and scavenging using striation patterns.

Thesis (MA)--University of Montana, 2009. / Contents viewed on November 30, 2009. Title from author supplied metadata. Includes bibliographical references.

Forensic taphonomy is concerned with investigation of graves and grave sites. The primary aim of forensic taphonomy is development of accurate estimations of postmortem interval (PMI) and/or postburial interval (PBI). Soil has previously been largely ignored, therefore this thesis is designed to investigate changes in decomposition as imparted by the soil. Furthermore the impact of cadaver interment on the surrounding soil may offer prospects for identification of clandestine graves. A series of laboratory controlled decomposition experiments using cadavers (Mus musculus) and cadaver analogues (skeletal muscle tissue (SMT); Sus scrofa, Homo sapiens, Ovis aries and Bos Taurus) were designed to investigate decomposition in burial environments. Sequential destructive harvests were carried out to monitor temporal changes during decomposition. Analyses conducted included; mass loss, microbial activity (CO2 respiration) and soil chemistry (pH, EC and extractable NH4 +, NO3 -, PO4 3- and K+). Several experimental variables were tested; frozen-thawed versus refrigerated SMT, different mammalian sources of SMT, different soil type and contribution of soil versus enteric microbial communities. Mass loss measurements for SMT experiments demonstrated a sigmoidal pattern of mass loss, however, larger cadavers (Mus musculus, 5 weeks) did not. The inhumation of SMT (frozen, unfrozen, different mammalian sources) or cadavers leads to an increase in microbial activity (CO2 respiration) within 24 hours of burial. A peak of microbial activity is attained within a week, followed by a decrease and eventual plateau. The rapid influx in microbial activity is matched by corresponding increases in pH and NH4 + concentration. pH and NH4 + are strongly correlated in soils with acidic basal pH, by comparison highly alkaline soil demonstrated no relationship. NH4 + concentration also appeared to be related directly to NO3 - concentration and cadaver or SMT mass. A decrease in NH4 + corresponds with an increase in NO3 -, however, nitrification was unpredictable. Rapid nitrification was observed in sand systems when SMT was interred, but was not noted when cadavers were interred. By comparison both sandy clay loam and loamy sand soils demonstrated rapid nitrification after inhumation of a cadaver. When cadaver or cadaver analogue mass was larger, so were NH4 + and NO3 - concentrations in systems that experienced nitrification.

Thesis (M.A.) -- University of Tennessee, Knoxville, 2005. / Title from title page screen (viewed on Feb. 2, 2006). Thesis advisor: Lee Meadows Jantz. Vita. Includes bibliographical references.

No / Despite an increasing literature on the decomposition of human remains, whether buried or exposed, it is important to recognise the role of specific microenvironments which can either trigger or delay the rate of decomposition. Recent casework in Northern England involving buried and partially buried human remains has demonstrated a need for a more detailed understanding of the effect of contrasting site conditions on cadaver decomposition and on the microenvironment created within the grave itself. Pigs (Sus scrofa) were used as body analogues in three inter-related taphonomy experiments to examine differential decomposition of buried human remains. They were buried at three contrasting field sites (pasture, moorland, and deciduous woodland) within a 15km radius of the University of Bradford, West Yorkshire, UK. Changes to the buried body and the effect of these changes on hair and associated death-scene textile materials were monitored as was the microenvironment of the grave. At recovery, 6, 12 and 24 months post-burial, the extent of soft tissue decomposition was recorded and samples of fat and soil were collected for gas chromatography mass spectrometry (GCMS) analysis. The results of these studies demonstrated that (1) soil conditions at these three burial sites has a marked effect on the condition of the buried body but even within a single site variation can occur; (2) the process of soft tissue decomposition modifies the localised burial microenvironment in terms of microbiological load, pH, moisture and changes in redox status. These observations have widespread application for the investigation of clandestine burial and time since deposition, and in understanding changes within the burial microenvironment that may impact on biomaterials such as hair and other associated death scene materials.

For the printed issue of the journal in which this article appears, please see the library catalogue.

Microorganisms are known to be agents involved in the decomposition of organic matter. However, little is known about the participation of the microbial communities during the decomposition of mammalian skeletal muscle tissue. This study investigates the capacity of the soil microbial community to adapt to the decomposition of skeletal muscle tissue in differing soils. This has implications for the study of mass graves and sites of repeated burial. A controlled laboratory experiment was designed to assess the adaptability of microbial communities present in three distinct soil types (sand, loamy sand and sandy clay loam) found near Perth, Western Australia. This experiment was split into two main stages. The initial decomposition stage involved the addition of porcine skeletal muscle tissue (SMT) (Sus scrofa) to each of the three soil types which were then left to decompose for a period of time. Controls were run in parallel, which had no porcine SMT present. The second decomposition stage involved a second addition of SMT to the soils obtained from the initial decomposition stage. Therefore, for each soil, SMT was either decomposed in the soil that had been pre-exposed to SMT or not. The rate of decomposition, microbial activity (CO2 respiration) and microbial biomass (substrate-induced respiration) were monitored during the second decomposition stage. The functional diversity of the microbial populations in the soil were assessed using Community-Level Physiological Profiling (CLPP). Across the three soil types, the re-introduction of SMT to the soil has led to its enhanced decomposition (measured by tissue mass loss and microbial activity) by the microbial communities. This microbial adaptation may have been facilitated by a functional change in the soil microbial communities.

[Truncated abstract] One of the standard ways of assessing time since death is from the stages of decomposition of the body. It is well known that the rate of decomposition is affected by environmental factors such as temperature and humidity. Another factor that can affect decompositional rates is the presence of breaches in the protective barrier of the skin, whether arising from antemortem injury or postmortem damage, including that occurring from animal necrophagy. Scavengers have the potential to affect decomposition by breaching the skin allowing access to associated insect material, feeding on the maggot masses, or by consumption of the carcass itself. Each locality will have its own set of features determining the rate of decomposition of the body, and variation may occur within localities based on the seasons. Such variation implies the need for local calibration of time since death against degree of decomposition and to establish the magnitude of interseasonal variation. When the localities are outdoors, the influence of potential scavengers, and the factors affecting their activity need also to be taken into account. This study investigates the interaction of environmental factors and animal scavenging on the rate of decomposition of pig (Sus scrofa) carcasses at four south-west Western Australia sites; Jandakot, Shenton Park, Perup Forest, and Watheroo National Park. Jandakot and Shenton Park are both close to the Perth metropolitan area and the western coast while Perup Forest is southern and inland and Watheroo is northern and inland. ... The most common insectivore feeding in relation to the carcasses was the Willie Wagtail (Rhipidura leucophrys) which was associated with the carcasses in all seasons and all locations except for Perup Forest. The breeding cycle appeared to have a marked influence on the intensity of scavenging by several species. The effect of season on decompositional rates was greatly reduced in carcasses that were exposed to scavenging. It took no additional time for carcasses to achieve skeletonization in winter than in the other seasons in the presence of scavenging. Scavenging had no significant impact on the rate of breakdown of carcasses in summer, when decompositional rates were greatest and scavenging at a minimum. v In Western Australia, it is not uncommon for bodies to remain undiscovered in bush environments for lengthy periods of time due to the low human population density. This study shows conclusively that it is not sufficient simply to consider the accumulated degree day (ADD) when estimating time since death by the degree of decomposition of the body. Attention must also be given to local wildlife assemblages and variations in their activities with the seasons. The implications of this research are in the determination of time of death. If the effects of scavengers accelerate decomposition this must be taken into account when any calculation since time of death is determined. The marked variations between sites in the rates of decomposition of carcasses exposed to natural animal scavenging in this study highlights the need for local calibration of time since death to decompositional stages for all locales. The techniques devised in this study are straight forward and easily conducted yet are informative and essential in determining time since death for bodies which have been exposed to animal scavenging.

Thesis (M.A.)--Texas State University-San Marcos, 2007. / Vita. Appendices: leaves 52-78. Includes bibliographical references (leaves 79-83).