New research from Texas State University has revealed that rock art from the Pecos River region dates back approximately 6,000 years and contains complex metaphysical imagery that significantly influenced the belief systems of various Mesoamerican cultures. The study, led by a team including Karen Steelman, Ph.D., Carolyn Boyd, Ph.D., and Phil Dering, Ph.D., was published in the journal Science Advances.
The researchers meticulously documented the distinctive Pecos River style murals, which Indigenous communities created over a span of more than 4,000 years. According to Boyd, who holds the position of Shumla Endowed Research Professor in the Department of Anthropology at Texas State University, “We have securely dated one of the most distinctive rock art traditions in the world.”
Through their work, the team collected 57 radiocarbon dates from 12 sites, finding that these polychromatic murals were painted in limestone rock shelters by forager societies in southwest Texas and northern Mexico. The murals, which feature humanlike, animal-like, and geometric figures, are arranged in deliberate compositions that can reach impressive dimensions—some measuring over 100 feet long and 20 feet tall.
The arid desert climate has played a key role in preserving these ancient artworks over millennia. Previous assumptions among archaeologists held that these expansive murals were created gradually over centuries, with various additions made by different communities. However, the recent radiocarbon dating analyses challenged this notion.
“Another huge shocker is that the dates within many of the murals clustered so closely as to be statistically indistinguishable,” Boyd noted. “This suggests that they were produced during a single painting event as a visual narrative.” This discovery contradicts the earlier belief that the murals were simply a random collection of images accumulated over extensive periods.
The research team utilized advanced techniques, including plasma oxidation and accelerator mass spectrometry, to achieve their findings. Bayesian modeling indicated that the Pecos River style likely originated between 5,760 and 5,385 years ago and continued until approximately 1,370 to 1,035 years ago.
Additionally, the analyses revealed that eight of the murals adhered to a specific set of compositional rules and an established iconographic vocabulary. This consistency in messaging persisted throughout a time marked by significant changes in material culture, land use, and climate conditions. The researchers concluded that the Pecos River style paintings, situated in a culturally significant landscape, conveyed sophisticated metaphysical concepts that later influenced the beliefs and symbolic expressions of Mesoamerican agricultural societies.
“The compositional nature of the murals was further supported by our analysis of the painting sequence,” Boyd explained. “Using a digital microscope to retrace the steps followed by the original artists, we discovered that the painters adhered to a rule-bound color application order.”
This careful technique led to intertwined paint layers that form intricate, well-planned compositions. Boyd emphasized that these murals are akin to visual manuscripts created according to traditional rules passed down through generations for over 4,000 years.
Perhaps one of the most significant aspects of this discovery is the connection modern Indigenous communities in the United States and Mexico have with the stories conveyed through these ancient images. Boyd remarked, “Think about it, the canyons of Southwest Texas house a vast and ancient library of painted texts documenting 175 generations of sacred stories and Indigenous knowledge.”
As both an artist and an archaeologist, Boyd described the findings as breathtaking, highlighting the enduring legacy of these visual narratives that have persisted for over six millennia. The implications of this research extend beyond mere historical curiosity; they underscore a pan-New World belief system that continues to resonate within Indigenous communities today.
