Melissa A. Connor

The archaeology of contemporary mass graves

The excavation of mass graves provides information and documentation for both human rights work and for forensic medico-legal investigations. Medico-legal documentation for the United Nations International Criminal Tribunal for the former Yugoslavia and the International Criminal Tribunal for Rwanda is a major reason for recent excavation of large mass graves in these countries. The mass grave excavations have been among the largest since World War II. The investigative teams incorporated professional archaeologists sensitized to medico-legal realities, to the realm of decomposed fleshed remains, and who exhibited flexibility in adapting techniques to the forensic context. This paper examines the forensic context of these excavations, the techniques the team developed, and presents a case study from Rwanda.

Metal detector use in archaeology: An introduction

Metal detectors are simple, effective, and inexpensive remote sensing tools with real value to archaeologists. The archaeologists is presented an overview of how to use a metal detector and outlines the physical principles that govern metal detectors and their limits. Examples of the use of detectors in inventory, testing, and excavation are drawn from the literature and from the authors’ experience.

Interobserver Reliability of the Total Body Score System for Quantifying Human Decomposition

Several authors have tested the accuracy of the Total Body Score (TBS) method for quantifying decomposition, but none have examined the reliability of the method as a scoring system by testing interobserver error rates. Sixteen participants used the TBS system to score 59 observation packets including photographs and written descriptions of 13 human cadavers in different stages of decomposition (postmortem interval: 2–186 days). Data analysis used a two‐way random model intraclass correlation in SPSS (v. 17.0). The TBS method showed “almost perfect” agreement between observers, with average absolute correlation coefficients of 0.990 and average consistency correlation coefficients of 0.991. While the TBS method may have sources of error, scoring reliability is not one of them. Individual component scores were examined, and the influences of education and experience levels were investigated. Overall, the trunk component scores were the least concordant. Suggestions are made to improve the reliability of the TBS method.

The Mountains Burnt: Forest Fires and Site Formation Processes:

The purpose of this article is to explore the effect of forest fires on the archaeological context in a mountainous environment. As Schiffer (1987) has pointed out, understanding environmental formation processes is integral to understanding site formation. Regional-scale processes, such as forest fires, have important site-level effects. By examining these effects in areas burned during the 1988 Yellowstone fires and by concurrently excavating nearby sites, site formation processes related to forest fires were examined. Important effects of fire which may be noted at the site-level include: 1) the mosaic burn pattern, where sharp boundaries are present between burned and unburned areas, 2) morphological changes to stone or bone should be limited to the charred layer representing the burn or within several centimeters below it, 3) specific oxidized soil features, and 4) ash pockets.

Testing the Use of Pigs as Human Proxies in Decomposition Studies

Pigs are a common human analogue in taphonomic study, yet data comparing the trajectory of decomposition between the two groups are lacking. This study compared decomposition rate and gross tissue change in 17 pigs and 22 human remains placed in the Forensic Investigation Research Station in western Colorado between 2012 and 2015. Accumulated degree days (ADD) were used to assess the number of thermal units required to reach a given total body score (TBS) (1) which was used as the measure of decomposition. A comparison of slopes in linear mixed effects model indicated that decomposition rates significantly differed between human donors and pig remains χ2(1) = 5.662, p = 0.017. Neither the pig nor the human trajectory compared well to the TBS model. Thus, (i) pigs are not an adequate proxy for human decomposition studies, and (ii) in the semiarid environment of western Colorado, there is a need to develop a regional decomposition model.

Comparing the Scoring of Human Decomposition from Digital Images to Scoring Using On-site Observations

When in forensic casework or empirical research in‐person assessment of human decomposition is not possible, the sensible substitution is color photographic images. To date, no research has confirmed the utility of color photographic images as a proxy for in situ observation of the level of decomposition. Sixteen observers scored photographs of 13 human cadavers in varying decomposition stages (PMI 2–186 days) using the Total Body Score system (total n = 929 observations). The on‐site TBS was compared with recorded observations from digital color images using a paired samples t‐test. The average difference between on‐site and photographic observations was −0.20 (t = −1.679, df = 928, p = 0.094). Individually, only two observers, both students with <1 year of experience, demonstrated TBS statistically significantly different than the on‐site value, suggesting that with experience, observations of human decomposition based on digital images can be substituted for assessments based on observation of the corpse in situ, when necessary.

The Ethics and Best Practices of Human Decomposition Facilities in the United States

ABSTRACT Taphonomists working with the recently dead find a lack of standards and best practices to guide them in the ethical treatment of human remains. The research is not covered by Institutional Review Boards (IRBs), where the federal guidelines specifically include “live human subjects.” Neither are the human dead covered in the guidelines issued by the U.S. Department of Agriculture for animal research. Most universities have no guidelines for research using the recently dead. Medical research has proposed some guidelines (1), however, taphonomic research differs in the longevity of the research and the disposition of the remains. The standards and ethics in working with the recently dead can be guided by the same fundamental principles outlined in the Belmont Report (2)–respect for persons, beneficence, and justice. This paper outlines some of the issues relevant to current decomposition research facilities and suggests guidelines and best practices.

Bioelectrical Impedance as a Technique for Estimating Postmortem Interval

Estimation of postmortem interval (PMI) is a critical component of death investigation. A cadaver can be hypothesized to be a resistor–capacitor (RC) circuit the impedance (Z) of which changes in a quantifiable manner as the cadaver decomposes. This hypothesis was tested using bioelectrical impedance analysis (BIA) equipment to apply a current with a fixed amplitude at a single frequency to four cadavers over time and measuring two components of Z, resistance (R) and reactance (Xc). Quadratic regression analysis between Z and accumulated degree days (ADD) showed a statistically significant parabolic relationship. The parabolic relationship poses an initial challenge to the use of the method, and additional research is needed to address this issue. However, the results of the reported research support the hypothesis that Z measured using BIA has a relationship to PMI.

Ceramics and Clay Nodules From Jackson Lake, Wyoming: Description and Mineralogical Analysis

This study focuses on the mineralogical analysis of clay artifacts from Grand Teton National Park, Wyoming. Included are 18 ceramic sherds, four clay nodules, and a control sample of natural clay. The purpose of the mineralogical analysis was to determine if the clay artifacts could have been made on site from local clays. The mineralogical analysis on the ceramic sherds and the local clay indicates the pot tery was not made in the immediate area, but possibly nearby, suggesting people in or near Jackson Lake knew how to make pottery and did not need to trade for it. Two clay nodules, one from each of two sites, were also submitted for mineralogical analysis. The two sites are separated geographically by about two miles and temporally by several hundred years. The two nodules, however, are made from the same clay source, which does not match the local clay. The temporal continuity of the clay source for the nodules and the importation of the clay suggest a cultural importance for the nodules not otherwise perceived.