Dating the Palaeolithic Cave Art of the Iberian Peninsular by Uranium-Seires

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Cave art is one of the few sources of archaeological information about the belief systems and aesthetic abilities of the earliest known artists, the hunter-gatherers of the European Upper Palaeolithic. It has been critical in defining cultural groupings and successions, and in recent years has been incorporated into discussions of cultural responses to climate change. While its specific meaning will probably always remain hotly debated, it is undoubtedly one of the most intimate windows to the cultural past. However, chronological uncertainty seriously hampers our understanding of nearly all aspects of rock art, especially its relationship to the unstable climate of the Upper Pleistocene and to the rest of the Upper Palaeolithic record. This project will redress this situation by producing one of the largest corpuses of radiometric dates for one of the core regions of Palaeolithic cave paintings and engravings, the Iberian Peninsula. The results will considerably improve our understanding of the distribution and changes over time of the art and relate this to the climatic background. Radiocarbon has been used to provide dates for the organic pigments used in rock art, but many of the results remain controversial. This is because organic pigments may become contaminated by the much older limestone of the walls of caves, or because the charcoal used to make a black pigment was itself old at the time the art was made. At present it is still not certain if the art appears around 32,000 or 18,000 years ago. Furthermore, radiocarbon can only date carbon based pigments, and the majority of early rock paintings are either engravings with no pigments, or use mineral pigments such as red ochre that is unsuitable for dating. However, some of these engravings and paintings are directly on, or are overlain by, calcium carbonate deposits similar to stalagmites and stalactites. The date at which these crusts formed can be determined by uranium-series dating, a technique that measures the ratio of uranium to its radioactive decay product thorium. Thus a minimum or maximum age can be calculated for the art, and by measuring enough different examples a chronology for the development and spread of different styles can be built up. This data will provide the basis by which we will understand how and when rock art first came about in Iberia, and its relationship to similar art in Southern France and the rest of Europe. We will investigate whether the appearance and subsequent intensification of rock art is related to rapid climatic change that occurs in the Late Upper Palaeolithic. Records of raipd transitions from warm to cold periods in the run up to the last glacial maximum have been revealed by marine sediment and ice cores. We will compare the frequency and date of the rock art to these climatic records to test the hypothesis that the intensification of artistic expression in caves was a social response to a changing climate.