Academic Reading — Test 161

Reading passage

In the tropical north of Australia, within the boundaries of Kakadu National Park, lies one of the richest concentrations of rock art anywhere on Earth. Across sandstone escarpments, overhanging shelters and isolated outliers, many thousands of painted and engraved images record the beliefs, observations and daily concerns of the Aboriginal peoples who have occupied this landscape for tens of thousands of years. Some galleries, such as those at Ubirr and Nourlangie, are visited by large numbers of tourists each year, while others remain known only to the traditional custodians who continue to regard the sites as living cultural places rather than relics of a vanished past. For the communities concerned, the art is not merely decoration; it is bound up with law, kinship and the continuing responsibility to care for country. The images themselves vary enormously in style, subject and apparent age. Among the most celebrated are the so-called X-ray paintings, in which animals and people are depicted with their internal organs and skeletal structures shown, as though the artist could see beneath the skin. Other panels record the arrival of European ships, firearms and even sailing vessels with figures wearing hats and boots, providing an indigenous perspective on the colonial encounter. Older layers include depictions of animals that no longer live in the region, and in some cases creatures that scientists believe became extinct long ago. Because newer paintings were frequently added directly on top of earlier ones, a single rock face may carry many superimposed images, each belonging to a different period and tradition. Establishing reliable dates for this art is, however, notoriously difficult. The pigments most commonly used were mineral based, drawn from ochres rich in iron oxide that contain no carbon, so the radiocarbon technique that has proved so valuable elsewhere cannot be applied to the paint itself. Researchers have therefore turned to indirect methods. One approach is to date organic material trapped in thin mineral crusts that form over the painted surface, since a layer lying on top of an image must be younger than the image beneath it. Another examines fragments of fallen rock bearing traces of pigment that have become buried in the floor of a shelter, where the surrounding sediment can be dated by other means. Each of these strategies yields a boundary rather than a precise figure, telling investigators that a painting is older or younger than a given point rather than fixing its exact age. The problems do not end there. Tropical conditions are unkind to ancient surfaces: heavy seasonal rain, wind-blown dust, insect nests and the growth of microorganisms all erode and obscure the images over time. Water running across a panel can dissolve and redeposit minerals, contaminating any crust that a scientist might hope to sample and distorting the result. Where a painting has been refreshed or repainted by later generations, as was often the practice, the surface may combine pigment of widely differing ages, so that a single sample blends old and new. For all these reasons, published dates are usually presented with wide margins of uncertainty, and claims of extreme antiquity are treated with caution until they can be confirmed by independent work. A further consideration is that scientific dating is not the only, or even the primary, way in which the age and meaning of the art are understood. The traditional owners possess detailed oral histories and a sophisticated knowledge of their own visual conventions, and many regard intrusive sampling of the paintings as disrespectful or simply unnecessary. Modern research in Kakadu is consequently conducted in close partnership with these communities, and a study may be modified or abandoned if custodians object. Some scholars argue that the cultural authority of the custodians should carry as much weight as a laboratory measurement, while others maintain that the two forms of knowledge answer different questions and need not compete. In practice, the most productive projects have been those that treat indigenous expertise and scientific analysis as complementary rather than rival accounts. What emerges from this combined effort is a picture of remarkable depth and continuity. Although the precise figures remain debated, there is broad agreement that people have been making images on these rocks for an extraordinarily long span, and that the tradition was never frozen but constantly renewed. The galleries of Kakadu are therefore best understood not as a fixed archive to be decoded once and for all, but as a record still being written, in which the difficulty of dating is itself a reminder of just how long and how living the human presence in this landscape has been.