The symbolic role of the underground world among Middle Paleolithic Neanderthals.

Cueva de Ardales in Málaga, Spain, is one of the richest and best-preserved Paleolithic painted caves of southwestern Europe, containing over a thousand graphic representations. Here, we study the red pigment in panel II.A.3 of "Sala de las Estrellas," dated by U-Th to the Middle Paleolithic, to determine its composition, verify its anthropogenic nature, infer the associated behaviors, and discuss their implications. Using optical microscopy, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, micro-Raman spectroscopy, and X-ray diffraction, we analyzed a set of samples from the panel and compared them to natural coloring materials collected from the floor and walls of the cave. The conspicuously different texture and composition of the geological samples indicates that the pigments used in the paintings do not come from the outcrops of colorant material known in the cave. We confirm that the paintings are not the result of natural processes and show that the composition of the paint is consistent with the artistic activity being recurrent. Our results strengthen the hypothesis that Neanderthals symbolically used these paintings and the large stalagmitic dome harboring them over an extended time span.