The image of a prehistoric man wearing animal skins hunting for wild animals is one that is familiar to us. What might be less familiar is the ‘waste not want not’ attitude they had towards the remains of a days kill. Being ever resourceful they were turned into artwork, clothing, religious objects, tools and toys. Now, scientists have developed a technique that can take a detailed look at these objects and provide insight into the lifestyles and evolution of craft techniques, as well as information on the planet’s biodiversity, making them not just cultural artefacts but also equally important natural history artefacts.
The technique, called Peptide Mass Fingerprinting (PMF), identifies collagen-based materials, such as mammalian guts and sinew commonly used in the manufacture of such prehistoric objects. While, traditional methods failed to pinpoint the source of the material and required specialists to carry out the analysis, PMF, can be conducted by a non-specialist, and provides the level accuracy and specificity required to identify the animal source of a material down to a specific species.
PMF begins with enzymatic breakdown of the sample, cutting long protein chains into small identifiable chunks (peptides). The peptide mixture forms a unique “fingerprint”, from which the species of origin can be determined from peptide-marker databases.
Using the method and a recently constructed sea-mammal database, scientists were able to identify two historic Alaskan kayaks: a Yup’ik vessel from the mid-nineteenth century and an Alutiiq vessel from the late nineteenth century. Kayaks were originally used as a sleek hunting vessel, constructed from animal skins stretching over wooden or whalebone frames. Stitching and skin samples were collected and analysed. The skin covering the Yup’ik kayak was found to be that of a bearded earless seal, while the stitching was made from caribou. The skin of the Alutiiq kayak was also found to be that of an earless seal, and the stitching was from a humpback whale. In addition to the kayaks, the team also analysed nearly 100 samples from 30 Alaskan native objects. In a relatively short period of time, they were able to identify objects of previously unknown origin, and also corrected wrongly assigned objects.
PMF is able to handle a considerably large amount of data and as such gives researchers, artisans and cultural groups valuable information into the biodiversity present at that time. The hope is that this in turn will lead to a better understanding of the preservation needs of historic and cultural artefacts for generations to come.
Kirby DP, Buckley M, Promise E, Trauger SA, Holdcraft TR. Analyst. 2013 Sep 7;138(17):4849-58. doi: 10.1039/c3an00925d. Identification of collagen-based materials in cultural heritage.
Modern Analytical Methods in Art and Archaeology, M.P. Colombini and F. Moodugno, John Wiley & Sons, Inc., New York, 2009.