Dating the origins and development of Palaeolithic cave painting in Europe by U-series disequilibrium

欧洲洞穴艺术是冰河时代考古中最引人注目的例子之一，也是关于已知最早艺术家的信仰体系、象征行为和审美能力的最重要信息来源之一。虽然它的具体含义可能一直备受争议，但它无疑是了解过去文化的最亲密的窗口之一。然而，对其确切年代的不确定严重阻碍了我们对洞穴艺术几乎所有方面的理解，特别是它与地下考古的关系，这些考古构成了冰河时期人类行为和行为变化的大部分记录。我们将通过为旧石器时代洞穴壁画和雕刻的核心地区提供最大的辐射测量日期库之一，在很大程度上纠正这种情况；西班牙，法国和意大利。结果将使我们能够确定尼安德特人是否创造了一些最早的艺术，或者它是否仅限于我们自己的物种；以及它的主题和风格是如何随着时间的推移而变化的。为特定的艺术主题和风格提供可靠的日期，将使我们能够将不断变化的艺术传统与地下考古记录中记录的社会和行为变化联系起来。目前还不能确定洞穴艺术最早出现在欧洲的时间。放射性碳已经被用来提供洞穴壁画中使用的有机颜料的年代，但许多结果仍然存在争议。有机颜料可能会被洞穴墙壁上更古老的石灰石污染，或者用来制作黑色颜料的木炭在艺术品制作时可能已经很旧了。此外，放射性碳只能测定碳基颜料的年代，但大多数早期洞穴艺术要么是没有颜料的雕刻，要么是使用不适合放射性碳测定法的矿物颜料，如红赭石。许多雕刻和绘画是直接在碳酸钙层上创作的，或者被碳酸钙层覆盖，碳酸钙层的形成过程与石笋和钟乳石的形成过程相同。我们可以通过铀系列测年来确定这些层是何时形成的，这是一种测量铀与其放射性衰变产物钍的比例的技术。通过这样做，可以计算出艺术的最小或最大年龄，并通过测量足够的例子来构建艺术出现及其随后发展和不同风格传播的年表。在一个试点项目中，我们成功地确定了西班牙北部11个洞穴中50个碳酸盐样本的年代，表明该地区的艺术出现的时间比之前认为的要早2万年，而且它出现在最后一批尼安德特人消失和第一批现代人（智人）到来的时期。这些结果提出了尼安德特人创造一些最早的洞穴艺术的可能性。如果这是真的，这将符合尼安德特人象征性地使用颜料的新图景，并将大大提高我们对他们的行为和认知能力的理解。要解开这个谜团，需要一个更雄心勃勃的计划，因为最早艺术的传播可能有助于我们了解它是否与第一批现代人一起到达欧洲；它是后来才被他们开发出来的吗？或者其中一些是否可以归因于尼安德特人。为了解决这些问题，我们将在洞穴艺术最丰富的地区的49个洞穴中确定与可测定的碳酸盐层相关的洞穴艺术；西班牙，法国和意大利，并制作了迄今为止最大的可靠年代洞穴艺术数据库。

European Cave art is one of the most striking examples of Ice Age archaeology and one of the most important sources of information about the belief systems, symbolic behaviour and aesthetic abilities of the earliest known artists. While its specific meaning will probably always remain hotly debated, it is undoubtedly one of the most intimate windows to the cultural past. However, uncertainties about its exact age seriously hamper our understanding of nearly all aspects of cave art, particularly its relationship to the archaeology that is found below ground and which constitutes the majority of the record of Ice Age human behaviour and behavioural change. We will considerably redress this situation by producing one of the largest corpuses of radiometric dates for the core regions of Palaeolithic cave paintings and engravings; Spain, France and Italy. The results will allow us to determine whether Neanderthals created some of the earliest art, or whether it was a behaviour restricted to our own species; and how it evolved thematically and stylistically over time from place to place. Providing reliable dates for particular artistic themes and styles will allow us to relate the changing artistic traditions to the social and behavioural changes that are recorded in the below ground archaeological record.At present it is still not certain when cave art first appeared in Europe. Radiocarbon has been used to provide dates for the organic pigments used in cave paintings, but many of the results remain controversial. Organic pigments may become contaminated by the much older limestone of the walls of caves, or the charcoal used to make a black pigment could have been old at the time the art was made. Furthermore, radiocarbon can only date carbon based pigments, but the majority of early cave art is either engravings with no pigments, or use mineral pigments such as red ochre that is unsuitable for the radiocarbon method. Many engravings and paintings were created directly on, or became overlain by, calcium carbonate layers formed by the same process as stalagmites and stalactites. We can establish when these layers formed by uranium-series dating, a technique that measures the ratio of uranium to its radioactive decay product thorium. By so doing a minimum or maximum age can be calculated for the art, and by measuring enough examples a chronology for the emergence of the art and its subsequent development and spread of different styles can be constructed. In a pilot project we successfully dated 50 carbonate samples from 11 caves in northern Spain, showing that art in this region appeared 20,000 years earlier that was previously thought, and that it appeared in the period in which the last Neanderthals were disappearing and the first modern humans (Homo sapiens) were arriving. These results raised the possibility that Neanderthals created some of the earliest examples of cave art. If true, this would fit with the emerging picture of symbolic use of pigments by Neanderthals, and would raise our understanding of their behavioural and cognitive capacities significantly. To unravel this requires a far more ambitious project, proposed here, since the distribution of the earliest art may help us understand if it arrived in Europe with the first modern humans; whether it was developed by them only later; or indeed whether some of it can be attributed to the Neanderthals. To address these questions we will date cave art associated with datable carbonate layers in 49 caves in the regions where cave art is most abundant; Spain, France and Italy, and produce the largest database of reliably dated cave art so far produced.