New technologies applied to modelling taphonomic alterations of human origins

Taphonomy is a discipline dedicated to the analysis of the different processes that influence the mechanisms of fossilization, affecting both fossils and their environment. In this sense, this research is focused on the premortem and postmortem processes affecting animal bones found in archaeological sites. Studies related to human evolution can be approached from different perspectives, being paleontological analyses the best procedure for identifying ancestors through fossils. Paleo-environmental studies explore the past environment and climate, conditioning human evolution and adaptation. On the other hand, archaeological studies (the area of this research), examine the material culture and behaviour of ancient populations.

 

Sites can be exclusively paleontological, with no human intervention, or archaeological, with evidence of human activity. In the latter, bones may have been altered by humans, carnivores, or natural processes. In this context, taphonomy allows to classify the origin of this alteration, being even possible to define the intervention of several agents on the same animal, such as humans, carnivores, and rodents, and the order of such intervention.

 

Evidence of human intervention on animals from the past is found in the marks left when processing meat or marrow. The analysis of cut and percussion marks is used to reveal the applied tools and methods. The research here presented is based on the implementation of technologies such as photogrammetry and geometric morphometry to document these marks in a three-dimensional way. Machine learning, deep learning, and advanced statistics are then applied to answer specific questions. In particular, three main key questions about human behaviour in past populations have been addressed:

 

What tools were used to process animal meat, and were there any preferences in raw materials? Three-dimensional reconstructions are applied to identify the morphology of cut marks and, through repeated experiments, determine which materials, such as flint, quartz, or volcanic rock, were used in the past.

 

Which carnivores occupied the sites after they were abandoned by humans, and how does this affect the paleoecology? Tooth marks on bones are analysed to differentiate with high reliability which carnivore handled a bone, providing relevant information on the paleoecological implications depending on the specific carnivore.

 

How does trampling affect bones exposed at sites, and what relevant information does it provide? Through trampling analysis, it is possible to determine when this occurred, providing important data on how long the bones were exposed before burial and the degree of site disturbance.

 

All the previous lines of research enable to assess site integrity, identify the carnivores involved, and understand human behavioural strategies in the processing of animal carcasses.