S15-5

A Novel Holistic Approach to the Taphonomic Analyses of Tropical Cave Fossils

Holly Ellen Smith1, Julien Louys1, Jahdi Zaim2, Yan Rizal2, Aswan2, Mika Rizki Puspaningrum2, Agus Trihiscaryo2

1Australian Research Centre for Human Evolution, Griffith University

2Geology Study Program, Institut Teknologi Bandung, Indonesia

Critically, conventional direct dating of fossils can form a timeline of hominin and associated faunal arrival, migration, settlement and extinction patterns. However, fossiliferous deposits in caves are not static; they are disturbed by complex depositional processes over long periods, particularly in tropical climates, and this can strongly affect stratigraphic integrity. These complex processes have made it difficult to ascertain the provenance of vertebrate remains in tropical cave environments and the taphonomic factors that influence them. Natural mixing processes in tropical caves could lead to several different ecosystems separated by tens of thousands of years appearing to have co-existed, which may have serious implications for our understanding of environmental change and biodiversity responses in the tropics, and thus reshape the narrative of our ancestor's colonisation and migration patterns. My research aim is to use a holistic approach to resolve mechanisms of site formation, depositional history, and faunal accumulation in tropical caves, vitally conserving the original integrity of excavated fossiliferous deposits to analyse taphonomic histories that would otherwise have been destroyed using conventional analyses and excavation methods. My research presents a unique taphonomic effort in the tropics to integrate multi-scale and multi-dimensional techniques to contextualise palaeontological material, namely neutron tomographic analysis and micromorphology. My contextual approach interprets the various formation processes rather than constructing sedimentation rates through direct dating methods, and thus underlines the biases inherent in the conventional techniques. This study generates a more complex and complete model of taphonomy and site formation history in tropical caves which has the potential to inform on the accuracy of previously calculated ages and the true contemporaneity of faunal remains contained within.