From March 10 to May 14, 2017, the Côa Museum presents the exhibition "Schist Pioneers - Biological processes of open-air rock art colonization". It is an exhibition of scientific dissemination, resulting from a partnership between the CIBIO of the University of Porto and the Côa Park Foundation, with the support of the Baixo Sabor Fund.
Open-air rock art is continually exposed to the colonizing action of the so-called pioneer organisms. With more than two hundred species recorded to date, lichens are among the most prolific pioneers of schist in the Côa Valley. The presence of lichens on engraved surfaces raises opposing views among specialists from different areas. The lichenologist considers the formation of the lichen mosaic a natural feature of the rocky surfaces, and the diversity of species aesthetically pleasing, as well as ecologically interesting, given the direct relationship between the composition of the flora and the passage of time. Those dealing with the preservation of rock art see lichens as unwanted invaders that can mask incisions and fine details and, depending on the present species and environmental conditions, cause damage to engraved motifs. Scientists developing research in cultural contexts cannot ignore the complexity of the effects of natural phenomena on heritage preservation, be they physical, chemical, and whether or not mediated by biological factors.
This exhibition seeks to synthesize this complexity. Through images, specimens and materials used in the course of the research and a few metaphors, it proposes a way through the various phases of the scientific study of the consequences of lichen colonization for the preservation of rock art in the open air.
Joana Marques, Helena Hespanhol and Cristiana Vieira | Curators of the exhibition