Tooth Marks of Mammalian Incisors on Rocky Substrate in Brazil: Evidence of Geophagy in the Cerrado Biome

Abstract

Tooth marks on sandstone in an area of the Cerrado Biome are reported, indicating geophagy. The tooth marks were found on reddish sandstones cropping out in a pasture environment with typical components of the Cerrado Biome, in the Municipality of Campina Verde, Triângulo Mineiro region (west Minas Gerais State, Brazil). Studies have shown that the soil of the Cerrado is acid, with a low concentration of nutrients and minerals (also present in the plants living on this environment), which usually produce an alimentary deficiency in herbivorous animals. Therefore, these tooth marks indicate geophagy, in order to extract extra minerals from these sandstone levels, which have a high concentration of calcium carbonate and iron. The tooth marks consist of two parallel concave grooves and a medial prominent crest which results from the action of the incisors of mammals. Although the identification of the gnawing species for these sets of tooth marks are estimates at best, after wide comparisons we tentatively suggest that the tooth marks are most likely the result of the action of the incisors of rodents, such as Dasyprocta or Coendou.