A Computed Tomography and Dissection Study of a Unique Ychsma Burial Bundle from the site of Pachacamac, Peruvian Central Coast

Abstract

AbstractComputed tomography (CT) scans of funerary bundles have become the convention for mummy studies, especially in Andean contexts. Increasingly high-resolution 3D imaging – as well as ethical issues surrounding the treatment of human remains, has led to the increasing conviction that mummy studies should be carried out using solely digital approaches. However, the fact that these approaches are non-invasive inevitably stymies our understanding of how accurate they are, compared to traditional unwrapping. A large, complex Ychsma bundle (dated to AD1020-1150) was recovered from Pachacamac, Peru, in 2018, and was analysed using a dual approach. A series of CT images were scored for bundle structure, body position, element presence, and anatomy/pathology; the bundle was then dissected and the data was compared. CT imaging performed well for body position, element presence and certain aspects of anatomy/pathology. However, the presence of radio-opaque inclusions following the internal deterioration in antiquity served to obscure various elements, while the CT was also unable to distinguish any of the layers of textile and botanical wrappings or any artefacts within them. The CT was also unable to determine that the bundle contained two individuals; the original individual had been partially removed and other elements incorporated, but as there was no element duplication the CT imaging could not differentiate the individuals. In addition to providing new information concerning bundle reprocessing and the use of trophy items among the Ychsma, this is both a support and cautionary tale towards the use of radiographic imaging in the analysis of Andean bundles.