Spectacular panoramas depicting ancient mammoths, rhinos, horses, and reindeer, known from such European caves as Lascaux, Niaux, and most recently Chauvet (see Natural History, May 1995) have dominated our understanding of Paleolithic art and society for more than a century. Now the rediscovery of numerous Paleolithic engravings in the Coa Valley of northeastern Portugal-first reported by a local physician in the 1930s-has forced a reexamination of how Paleolithic people used art.
The Coa's stylized drawings of animals, most of them created some 20,000 years ago, were not made in the dark, subterranean caves that have long linked prehistoric art to secret initiations and hunting magic. Instead, the pictures are scattered outdoors at prominent sites along the course of the Coa River. Such artworks may have been the rule rather than the exception during the Paleolithic. They may have been used for such practical purposes as demarcating group territories, identifying hunting grounds and fords, or commemorating past events.
So far, twenty-two clusters of Paleolithic rock art have been found in the valley, encompassing 214 panels and about 1,200 individual engravings. (The final tally of images is far from complete, as only two clusters have been systematically surveyed.) The engravings apparently represent an uninterrupted prehistoric sequence, stretching from 20,000 years ago until about 2,000 years ago. (Because the drawings lack datable pigments or charcoal, the dating is done principally by stylistic comparison with cave art of known age.) Etched on vertical schist surfaces, the designs are classic Paleolithic depictions of aurochs (ancient wild cattle), horses, ibexes, red deer, and fishes-all Pleistocene fauna found in Iberia. Some have previously unknown stylistic features, particularly the depiction of animals' heads and forequarters in multiple positions to indicate movement.
In 1992, a government survey team rediscovered some of the engraved animals at a site that was to be flooded by the massive Foz Coa dam project. Two years later, in November 1994, the Portuguese government announced the existence of the Coa petroglyphs, setting off a national debate. Even as an electric company was working in the valley in 1995, a panel of conservation experts from UNESCO determined that the engraving were authentic. In November of that year, work on the dam was halted, and $5 million has since been invested in creating a permanent archeological park.
I had been excavating Paleolithic and Neolithic sites and studying early Neolithic pottery in Portugal for a decade. Like everyone else in the archeological community, I was stunned by news of the engravings and wanted to have a look at them. I was delighted, therefore, when Joao Zilhao, the director of the newly created Parque Arqueologico Vale do Coa, invited me and my young son to visit the valley. (Joao had been instrumental in preserving and documenting the petroglyphs.)
On our drive from Lisbon, we passed among the limestone cliffs of the Estremadura, over the granitic plateau of the Douro, and then into the schist valleys of the upper Douro and Coa Rivers. Our first destination, the town of Vila Nova de Foz Coa is on a plateau above the confluence of the Douro and the Coa, which drains north from the Serra da Estrela, Portugal's highest mountain. …