Scrimshaw : unlocking the cultural and biological archive of sea mammal art

During the middle decades of the nineteenth century the folk-art tradition 'scrimshaw', predominantly using the teeth of sperm whales (Physeter macrocephalus), flourished among the crews of industrial whaling ships. Scrimshaw collections represent a unique cultural and biological archive of pre-industrial/industrial sperm whale populations, but the rarity, collectability, and high value of genuine nineteenth century scrimshaw specimens have precluded meaningful scientific investigation. Building on classical art historical methods, the multidisciplinary approach applied in this thesis allows for the examination of scrimshaw artefacts beyond imagery and carving techniques, providing additional insight into the biological history of the whales caught through detailed micro-computed tomography (micro-CT) scanning and biomolecular analysis. The Scott Polar Research Institute (SPRI), in Cambridge, United Kingdom, holds a significant collection of pictorial sperm whale scrimshaw from the early nineteenth century, depicting clear British iconography/imagery. Relevant scrimshaw specimens from the SPRI collection, and undecorated sperm whale teeth, were scanned utilising high-powered micro-CT technology to investigate internal tooth morphology, assess preservation, and create a digital archive of the artefacts prior to, and post, destructive sampling. This research demonstrates that high powered micro-CT imaging can reveal more detailed information about the internal structure of sperm whale teeth and scrimshaw specimens than has been achieved in past studies. Dentine samples were then taken from the concave tooth roots of select samples for biomolecular analysis. This study demonstrates the efficacy of a novel sampling method using medical bone scrapers that better facilitate in situ sampling of scrimshaw artefacts and ivory in museum collections than traditional sampling methods such as drilling and longitudinal sectioning. For this study, biomolecular analysis was primarily utilised to molecularly sex the scrimshaw specimens, and to determine the efficacy of the selected sampling technique for collagen extraction and stable isotope analysis. This research illustrates that biomolecular analysis of scrimshaw artefacts can provide valuable biological and ecological information about pre-industrial/industrial nineteenth century sperm whales.