Some lines are set out to frame pyramid structures, Stanish said. The lines are parallel, but because parallel lines seem to converge with distance, these framing lines appear to point directly at pyramids. Other lines run parallel to roads that are still used today, Stanish said.
The desert lines and mounds are about 9 miles (15 km) from settlements near the coast. Stanish and his colleagues suspect that the ancient "fairgrounds" were built on land that was useless for farming and were intended to attract tradespeople and buyers from the coast and the Andes highlands.
The mounds, pyramids and lines were likely the ancient version of neon signs, Stanish explained: "We're expending time and effort and resources to make our place bigger and better," he said, explaining the mindset of those who created the constructions. The various settlements on the coast probably competed to attract the most participants to their own fairs.
To confirm this notion, the researchers plan to excavate pyramids near the coast, looking for artifacts that would link settlements to the desert lines and mounds.
The discovery of these older rock lines emphasizes the geoglyphs had more than one function, Stanish said. People have long looked for "the" reason for the Nazca lines, but it's more accurate to think of the lines like multi-purpose technology, he said.
"The lines are effectively a social technology," Stanish said. "They're using it for certain purposes. Some people have said the lines point out sacred mountains. Sure, why not? The lines point out sacred pyramids. Why not? The lines could be used to point out processions," Stanish said of both the Nazca and Peru lines.
In that way, Stanish said, the lines are like pottery: one invention used for multiple purposes.
"Native Americans in this part of the world were extremely ingenious," he said.
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