The Micro-Taphonomy of Cold: Differential Microcracking in Response to Experimental Cold-Stresses.

Cold is a central feature of environments at higher latitudes and elevations. Thus, cold-induced taphonomic changes are relevant in many forensic contexts. Fifty-two lamb bone segments were used to assess the impact of cold, freeze-thaw cycles, freeze-drying, and water immersion on microstructural cracking of bone in a series of controlled exposure experiments. For each bone segment, three thin sections were examined under a light microscope. Cold exposure caused taphonomic changes in the form of microscopic cracking. Transverse cracks occurred in all treatments, whereas osteonal cracks were restricted to rapid freezing treatments. Type of cold exposure had a statistically significant effect on both the total number of cracks and each type of crack observed. Skeletal microcracking could potentially be used as a taphonomic indicator of postmortem bone exposure to sub-zero temperatures. The type and prevalence of this damage could also be used to distinguish between different types of cold exposure.