Periodic Reporting for period 1 - TaphArt (TaphArt: exploring the potential existence of rock art paintings in the Middle Stone Age of southern Africa and its destruction due to the action of taphonomic processes)
Reporting period: 2023-09-01 to 2025-08-31
The advent of symbolic material culture and the storage of information outside the human brain through the production of artefacts and images imbued with meaning was a landmark in human evolution. Although it has been generally considered as the consequence of an European Upper Palaeolithic "revolution" that took place around 40 ka, new evidence from the Middle Stone Age (MSA, ~300–40 ka) suggests the presence of symbolic material culture in Africa at ~150 ka. In this context, a major research challenge for archaeology is to explain the apparent absence of rock art paintings in the MSA archaeological record of southern Africa. Ochre pigments are ubiquitous in the sites from this period, and toolkits used to produce ochre-rich liquid paint date from at least ~100 ka. Furthermore, images engraved on pieces of ochre and a crayon drawing demonstrate that the MSA populations had all the material, technical and cognitive resources necessary to create graphic representations.
Thus, through an innovative and interdisciplinary approach that brings together an international team of experts in archaeology, paleoenvironmental science, atmospheric science, material science, and analytical chemistry—from the University of Bordeaux, the University of the Basque Country, and the German Aerospace Center—the TaphArt project aims to develop an experimental research to systematically investigate whether the absence of rock art paintings in the MSA sites of southern Africa is due to a cultural choice of the human populations or the result or taphonomic processes that eliminated the painted images from the archaeological record.Taking as reference the archaeological and paleoenvironmental context of Blombos Cave (South Africa) (Fig. 1), the project tests the hypothesis that marine aerosol and wind erosion may have contributed to the destruction of rock art paintings potentially produced on the site. In this sense, the data generated through accelerated ageing experiments and the application of archaeometric techniques, such as 3D digital and confocal microscopy, micro-EDXRF mapping, Raman spectroscopy, and hyperspectral imaging, are providing groundbreaking unprecedented insights into the origins of rock art and the behavioural evolution of Homo sapiens.
Thus, through an innovative and interdisciplinary approach that brings together an international team of experts in archaeology, paleoenvironmental science, atmospheric science, material science, and analytical chemistry—from the University of Bordeaux, the University of the Basque Country, and the German Aerospace Center—the TaphArt project aims to develop an experimental research to systematically investigate whether the absence of rock art paintings in the MSA sites of southern Africa is due to a cultural choice of the human populations or the result or taphonomic processes that eliminated the painted images from the archaeological record.Taking as reference the archaeological and paleoenvironmental context of Blombos Cave (South Africa) (Fig. 1), the project tests the hypothesis that marine aerosol and wind erosion may have contributed to the destruction of rock art paintings potentially produced on the site. In this sense, the data generated through accelerated ageing experiments and the application of archaeometric techniques, such as 3D digital and confocal microscopy, micro-EDXRF mapping, Raman spectroscopy, and hyperspectral imaging, are providing groundbreaking unprecedented insights into the origins of rock art and the behavioural evolution of Homo sapiens.
The TaphArt project successfully carried out an innovative experimental research programme to investigate whether the absence of Middle Stone Age (MSA) rock paintings in southern Africa is due to cultural choices or to the action of natural destructive processes. Fieldwork at Blombos Cave (South Africa) and its surroundings provided geological samples, ochre pigments, and dune sands used to prepare experimental supports replicating the local archaeological context. On these supports, experimental paintings were produced following eight different pictorial recipes (combinations of pigments and binders). The experimental samples were then subjected to accelerated ageing tests under controlled laboratory conditions. Two main types of experiments were performed: Marine aerosol simulations in climatic chambers, where variables such as humidity and temperature were controlled. Wind erosion simulations in sandstorm chambers and erosion tubes, where wind speed, particle concentration, and particle size were systematically varied. All samples were documented and analysed using an advanced multi-analytical protocol that included 3D digital microscopy, Raman spectroscopy, micro-XRF mapping, hyperspectral imaging, and colourimetry. These analyses generated, for the first time, large experimental datasets describing in detail how different environmental variables affect the preservation of ochre-based paints. Preliminary results demonstrate clear patterns of degradation. Differences in pigment survival are linked to the type of binder used, with some recipes proving more resistant to erosion. Wind speed and particle concentration were shown to be decisive in accelerating pigment loss, while marine aerosol caused specific chemical and physical alterations that can now be quantitatively described. Although data analysis and modelling are still in progress, the experiments have already established a robust empirical foundation for predictive models of rock art preservation in coastal environments. These models will make it possible to evaluate how long painted images could survive under past environmental conditions, providing unprecedented insights into the role of taphonomy in shaping the archaeological record. In summary, the project achieved its scientific objectives by designing and completing a pioneering programme of experimental archaeology, producing unique empirical data on rock art taphonomy, and laying the groundwork for predictive models that can be applied to Middle Stone Age sites and beyond.
The TaphArt project generated the first large-scale experimental datasets on the long-term impact of marine aerosol and wind erosion on ochre-based rock paintings. Until now, the absence of Middle Stone Age (MSA) paintings in southern Africa had been interpreted mainly through cultural hypotheses. TaphArt moves beyond this by providing solid empirical evidence that taphonomic processes could have played a decisive role in the preservation—or loss—of painted imagery. This represents a paradigm shift in the study of the origins of symbolic behaviour, as it demonstrates that the absence of evidence in the archaeological record cannot be simply equated with evidence of absence.
Methodologically, the project goes beyond the state of the art by designing and implementing a pioneering actualistic experimental programme that integrates climatic chambers, sandstorm chambers, and advanced archaeometric techniques. The resulting reference datasets offer, for the first time, quantitative criteria to assess the specific impacts of environmental variables such as wind speed, particle concentration, and marine aerosol composition on painted rock surfaces. This contribution establishes the foundations of a new research line—rock art taphonomy—with applications that extend beyond Africa to coastal and inland contexts worldwide.
The potential impacts are significant. In science, the results will refine models of human cognitive and symbolic evolution by reassessing the archaeological visibility of early artistic behaviour. In heritage management, the data provide a robust baseline to design more effective and low-cost conservation strategies for rock art exposed to environmental risks, particularly in resource-limited regions. The predictive models under development will serve as tools for evaluating preservation potential in specific sites, guiding monitoring strategies and preventive conservation.
Future uptake and success will depend on continuing three complementary lines of action: (1) further experimental research to expand the range of variables and binders tested, and to apply the methodology to other sites in southern Africa and beyond; (2) internationalisation and collaboration with heritage agencies to integrate predictive modelling into site management plans; and (3) open science practices to ensure that the datasets and protocols are accessible, interoperable, and reusable by researchers, conservators, and policy-makers.
In this way, TaphArt not only advances archaeological knowledge but also creates a replicable framework with wide-ranging implications for heritage conservation, interdisciplinary science, and the understanding of symbolic behaviour in deep time.
Methodologically, the project goes beyond the state of the art by designing and implementing a pioneering actualistic experimental programme that integrates climatic chambers, sandstorm chambers, and advanced archaeometric techniques. The resulting reference datasets offer, for the first time, quantitative criteria to assess the specific impacts of environmental variables such as wind speed, particle concentration, and marine aerosol composition on painted rock surfaces. This contribution establishes the foundations of a new research line—rock art taphonomy—with applications that extend beyond Africa to coastal and inland contexts worldwide.
The potential impacts are significant. In science, the results will refine models of human cognitive and symbolic evolution by reassessing the archaeological visibility of early artistic behaviour. In heritage management, the data provide a robust baseline to design more effective and low-cost conservation strategies for rock art exposed to environmental risks, particularly in resource-limited regions. The predictive models under development will serve as tools for evaluating preservation potential in specific sites, guiding monitoring strategies and preventive conservation.
Future uptake and success will depend on continuing three complementary lines of action: (1) further experimental research to expand the range of variables and binders tested, and to apply the methodology to other sites in southern Africa and beyond; (2) internationalisation and collaboration with heritage agencies to integrate predictive modelling into site management plans; and (3) open science practices to ensure that the datasets and protocols are accessible, interoperable, and reusable by researchers, conservators, and policy-makers.
In this way, TaphArt not only advances archaeological knowledge but also creates a replicable framework with wide-ranging implications for heritage conservation, interdisciplinary science, and the understanding of symbolic behaviour in deep time.