Paleontology and archeology have combined in north-eastern Brazil, where a 'magnificent' site has been discovered featuring dinosaur footprints alongside ancient rock carvings.
The Cerote do Letrero site, in the municipality of Sousa, Paraíba State, is home to three major rock outcrops, where fossilized footprints of theropods, sauropods, and iguanodon dinosaurs from the Early Cretaceous (145 to 100.5 million years ago) have been discovered. Not only this, the area is also home to petroglyphs – a type of rock art made by directly tapping on the surface of rock – created by humans in the pre-colonial period.
In a new study, researchers describe this “priceless” intersection of fossil and archaeological elements, the likes of which have never been seen in such close proximity before.
Dinosaur traces and associated rock art have been found before – in Australia, Poland and Utah, for example – but “in none of these cases have the petroglyphs shown such a close relationship with footprints as at Cerote do Letrero.” The researchers write in their study.
“There is no doubt that engravers recognized the footprints and deliberately executed petroglyphs around them, creating a symbolic connection between human graphic expression and the fossil record.”
Petroglyphs and Dinosaur Footprints at Outcrop 1. Theropod footprints are in white and the petroglyphs are in orange.
The first mentions of dinosaur footprints from the area date back to the early 1900s, and the paleontological aspects of the site have been studied several times in the years since. However, the petroglyphs have received much less attention, as they have not been comprehensively analyzed or considered together with footprints.
To correct this, the team surveyed the site, identifying three large outcrops where dinosaur footprints and petroglyphs were observed. In the first outcrop, an additional 22 clades were discovered, along with the highest concentration of theropods – the clade to which they belong. T-Rex Belong – Tracks.
Theropod footprints (AF) are closely related to the petroglyphs (D and F).
The second contains only two petroglyphs, although there appear to be many more that have since fallen illegible. In the third and final outcrop, 30 petroglyphs were identified, as well as extensive puncture marks and tracks left largely by sauropod dinosaurs.
Researchers have discovered that the petroglyphs are mostly circular and feature radial lines and other decorations. Although their meaning is not clear, they can be interpreted as geometric shapes, and bear a striking resemblance to rock carvings found elsewhere in Paraíba and Rio Grande do Norte. Some stand out designs, including rectangular mesh patterns and others that resemble stars and snakes.
Petroglyphs from Outcrop 3.
The difference in style suggests that several individuals were behind the rock art. We may not know who they were, but we do know that they took great care when carving next to the dinosaur footprints.
“In none of the cases was it found that the creation of the petroglyphs resulted in damage to the existing footprints, which indicates the thoughtfulness of the makers of these petroglyphs,” the team explains.
Serote do Letrero's “distinct juxtaposition” between paleontology and archaeology, according to the researchers, suggests that humans in pre-colonial Brazil engaged with the fossil record, actively incorporated it into their graphic expressions, and used it to help define their cultural identity.
As such, the study's authors call for its preservation, calling for “immediate mitigation measures to prevent further damage,” so that we can continue to appreciate this unique site for years to come.
The study is published in Scientific reports.
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