Manmade mounds shaped like orcas, condors and even a duck may be the oldest evidence of animal mounds outside of North America, according to Live Science. University of Missouri anthropologist and professor emeritus Robert Benfer described a series of mounds in coastal valleys in Peru. Archaeological evidence at the animal mound sites puts some of them at more than 4,000 years old.
The mounds were found in a region known for the Nazca lines (a series of giant animal outlines drawn on the ground), the ruined city of Chan Chan, and other cultural treasures, reported Futurity. They range from five meters (16.5 feet) to 400 meters (1,312 feet) long. Predating ceramics, they were probably built using woven baskets to carry and pile up rock and soil.
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"The finding of animal effigy mounds where there were none before changes our conception of early Peruvian prehistory," Benfer said to e! Science News. "That they probably represent the Andean zodiac is also a new find. A controversial interpretation of some Nazca figures as representations of the zodiac is supported by these mounds."
Benfer discovered the mounds while looking at satellite photos of a site that he'd long been curious about, according to Live Science. What he saw seemed to be shaped like a condor, he said, but previous archaeological knowledge suggested that animal effigy mounds were a North America-only phenomenon, with few exceptions, such as one at a site in Mexico.
"The mounds will draw tourists, one day," said Benfer to Futurity. "Some of them are more than 4,000 years old. Compare that to the effigy mounds of North America, which date to between 400 and 1200 AD. The oldest Peruvian mounds were being built at the same time as the pyramids in Egypt."