The 89th Annual Meeting of the American Association of Physical Anthropologists (2020)

An Investigation of the Inter and Intra Post Mortem Microstructural Change Seen in an Experimental Series of Pigs Exposed to a Marine Environment


School of Criminology, Simon Fraser University

April 18, 2020 4:45PM, Diamond 8-9 Add to calendar

The identification of post-mortem microstructural change to human bone can provide information on decompositional history and body deposition. The objective of this study was to assess the total distribution of post-mortem microstructural change within and between individual marine-submerged pig skeletons. An experimental series consisting of 14 juvenile pig carcasses were submerged within the Strait of Georgia B.C., between four to eight months. Seven pigs were individually submerged within caged platforms and the remaining seven were tied to open platforms. For this study, six elements were selected from each carcass: first rib, radius, ulna, middle-rib, tibia, and femur. Two transverse thin sections were sampled at each bone mid-shaft (n=148) and examined using circularly polarized transmitted light. The distribution of tunneling was assessed by measuring maximum ingress and tunnel diameter at 40 locations of the peripheral cortex. Results of analysis indicated peripheral tunneling from the periosteum to the central cortex. Tunnels were observed as radiating, bifurcating, and also observed as isolated tunnels and in clusters. All element types were impacted by tunneling. Tunnel diameters ranged between 2.00mm to 11.96mm, with a 3.1mm mean. Ingress measurements ranged between 7.54mm to 253.43mm with a 91.82mm mean. Distribution of post-mortem microstructural change across skeletal elements showed the averaged maximum penetration ingress was deeper in the uncaged (98.52mm), when compared to caged material (72.57mm). The averaged tunnel diameters showed a non-significant difference between uncaged and caged elements. Knowledge of marine post-mortem microstructural change assists the interpretation of events produced by different environments.

This work was supported by DDRC and CFI/BCKDF funds to LSB