Graduation Year

2010

Document Type

Thesis

Degree

M.A.

Degree Granting Department

Anthropology

Major Professor

Erin Kimmerle, Ph.D.

Committee Member

Lorena Madrigal, Ph.D.

Committee Member

David Himmelgreen, Ph.D.

Keywords

indoor environments, forensic anthropology and taphonomy, postmortem interval, human rights, time since death estimation

Abstract

Where do people die alone when they remain undiscovered for extended periods of time? Estimation of the postmortem interval (PMI) is critical to reconstructing the events surrounding a person's death and this is an area in which forensic anthropologists have played a leading role. This thesis applied an anthropological framework that takes a comprehensive approach to analyzing the demography of unaccompanied deaths, the relationships and timing of decomposition in multiple depositional contexts, and created a model for the prediction of accumulated degree days (ADD) for bodies within enclosures.

While there have been extensive experimental and case study reviews on decomposition in outdoor environments, very little data exist for enclosed spaces. A retrospective analysis of 2003-2008 Nebraskan autopsy records demonstrates that most people dying alone are within their homes. Of the 87 forensic cases reviewed, 69 unaccompanied deaths occurred within enclosed environments. The value of retrospective studies in combination to experimental research is that the large number of variables that affect decompositional rates may be explored in a natural context. Multivariate models put emphasis on the dynamics of decompositional change and comprehensively address death and decomposition within an anthropological framework.

For enclosed depositions, the PMI ranged from 1 - 66 days (n= 64, X¯=4.84, s.d.=9.1037) and the ADD ranged from 0 - 786 ADD (n=64, X¯=67.43, s.d.=120.275). Bass' (1997) model for outdoor surface decay was found to be an adequate predictor of the PMI for this sample (r=0.829, n=64, p≤0.000). A relationship was identified between ADD and stages of decomposition (r=0.585, p≤0.000, n=64). A Nonparametric Kruskal-Wallis test revealed that there were significant differences in ADD among stages of decay. These results provided support for the prediction of ADD as a measure of the rate of decomposition.

Relationships among ADD and multiple intrinsic, extrinsic and epidemiological variables were identified and considered for a multiple linear regression model. Variables selected by the model included: decomposition odor, use of air conditioning/heat, marbling, brain liquefaction, and mummification. The model was found to account for 95.2% of the variation in ADD (Adjusted R2 =0.952; F=40.807, df=5, 5 and p≤0.000).

Download

Share

COinS