This report presents the findings and methodology of a study to determine whether non-human animals exhibit the same forensically important characteristics as humans during decomposition.
The three objectives of this study were to 1) apply the Total Body Scoring (TBS) system to make quantitative morphological comparisons between species during decomposition; 2) assess insect taxonomic diversity and density differences among individuals and species; and 3) evaluate whether scavenger species and behavior differ among subject species and individuals. The project was conducted at the Anthropology Research Facility at the University of Tennessee, Knoxville. It compared five human, five domestic pig, and five domestic rabbit subjects in each of three seasonal trials. Overall, the study determined that human data are best for determining human patterns of decomposition in forensic cases. There was differential decomposition among humans and non-human animals. Rabbits do not make a suitable proxy for humans, since they were consistently different in their decomposition rates and pattern and did not allow the application of any morphological scoring system that can be applied to humans. Pig decomposition was closer to humans, but still differed in overall decomposition trends. This means that pigs could be useful for certain baseline decomposition data, but lack variability found in the human decomposition patterns. The intensity and pattern of scavenging observed on the human subjects was not captured by the non-human subjects, and insect activity may not be as impactful for humans as it is for pigs. Seasonality also had a role in differential decomposition, since pigs and rabbits decomposed faster than humans when insects were present. Also, scavenging was more likely to occur in the winter. A listing of 4 scholarly conference presentations on the study in 2016 and 2015, and 2 publications in process.