UTILIZING X-RAY TOMOGRAPHIC MICROSCOPY TO SYSTEMATICALLY TRACK DECAY IN TAPHONOMIC STUDIES

For over 30 years, laboratory decay experiments have proved valuable to our understanding of the taphonomic histories of soft-bodied fossils. Previous studies have considered a suite of facilitating factors and their potential in aiding with preservation. Regardless of the tested variables, data collection and subsequent analysis in these studies have generally relied upon visual assessments, qualitative decay scoring, and selective scanning electron microscopic techniques. While these studies have revealed a wealth of knowledge, the variable nature of their protocols and individualized scoring systems has made comparisons between studies difficult. Herein, we have established a new protocol for experimental decay studies using microcomputed x-ray tomography (µCT) to provide directly quantifiable data permitting better comparison between studies. While CT has been used in paleobiological studies, it has yet to be utilized in a full taphonomic study to interpret organismal decay. We use these methods to systematically track decomposition of peppermint shrimp (Lysmata wundermanni) through quantitative volumetric assessment and compare our data to the results of previous studies to test the validity of our methods. Our protocol shows potential to improve the evaluation of decay through nondestructive observation of never before captured organic materials in full three-dimensional analysis over time. Continued refinement of this methodology would allow for future work to systematically track decay under varying conditions, correlate taphonomic histories, and provide important information to help identify the taxonomy of fossil materials.