Archeologists have found nearly 5,000 cave paintings made by hunter-gatherers in a northeastern Mexico mountain range where pre-Hispanic groups were not known to have existed.
The yellow, red, white and black paintings depict humans, deers, lizards and centipedes, suggesting that the groups hunted, fished and gathered food, according to the National Anthropology and History Institute (INAH).
They also painted religious, astronomical and abstract scenes and most of the images are very well preserved.
The archeologists were not able to date the 4,926 paintings, but they could conduct chemical and radiocarbon analyses to try to determine how old they are.
The ancient artwork was discovered in 11 different sites in the caves and mountain gaps of the municipality of Burgos in the state of Tamaulipas, which borders the United States. More than 1,550 images were painted in one location dubbed "The Cave of Horses."
"It's important because with this we were able to document the presence of pre-Hispanic groups in Burgos, where before we said there were none," said archeologist Martha Garcia Sanchez of the Autonomous University of Zacatecas.
The paintings were made by at least three groups known as the Guajolotes, Iconoplos and Pintos. There is evidence that other groups moved around the San Carlos mountain range, such as the Cadimas, Conaynenes, Mediquillos, Mezquites, Cometunas and Canaimes.
"These groups escaped Spanish control for almost 200 years," Garcia Sanchez said. "They fled to the San Carlos mountain range where they had water, plants and animals to eat. The Spaniards didn't go into the mountain and its valleys."