A Comparison of Human and Domestic Pig Decomposition Using Multivariate Methods

Animal proxies are frequently used to substitute for human remains in decomposition studies. Domestic pigs have become the most commonly used nonhuman proxy due to an assumed similarity in decomposition progression to humans. This dissertation directly compares decomposition patterns along morphological indicators, insect activity and scavenging to assess if decomposition between humans and domestic pigs is similar enough such that data produced from a pig model can accurately predict human patterns. This study examines 15 human donors to 15 domestic pigs across three seasons. The data are analyzed with multivariate methods, including hierarchical linear modeling and dynamic linear regression time series analysis. The results of this study suggest that when examining decomposition as an entire complex process, patterns differ between domestic pigs and humans. Individual similarities in specific variables do exist, but the overall patterns differ between species to an extent that pigs cannot substitute for humans in all taphonomic and decomposition research, especially where the goal is to improve estimations of the postmortem interval.