April 2, 2012 -- Huge prehistoric effigy animal mounds, dating to thousands of years ago, have been found along the coastal plains of Peru. Similar enormous animal-shaped mounds are known to exist in North America, such as the Serpent Mound in Ohio.
The new finds, documented in the journal Antiquity, include mounds that were built at around the same time as the pyramids in Egypt.
The project's leader Robert Benfer, a University of Missouri anthropology professor emeritus, believes the raised earthen mounds were built as terrestrial manifestations of constellations the ancient Peruvians saw in the stars above.
"The finding of animal effigy mounds where there were none before changes our conception of early Peruvian prehistory," Benfer said. "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."
This image is of a mound shaped like an orca, an animal regularly hunted. According to Benfer, this effigy dates to approximately 5,000 years ago.
The Peruvian animal effigy mounds range in size from 16.5 to 1,312 feet long.
"They are not constructed on hillsides, but in the alluvial valley floor," Benfer said. "Their shape can be seen from the nearby hills in most cases."
This image shows a ground view of a condor-shaped mound. Condors, large vultures with mainly black plumage, are native to the high Andes.
The mounds, which predate ceramics, were probably built using woven baskets to carry and pile up rock and soil.
"Until our team found these (mounds in Peru), no other giant animal effigy mounds had been reported outside of North America," project leader Robert Benfer, a University of Missouri anthropology professor emeritus, told Discovery News.
The condor mound, located at a site called El Paraiso, is situated next to this stone sculpted condor head.
Benfer shares that such stone condors are common in the Andes, but this is the first one found on the coast. When viewed from the entrance to a 4,000-year-old temple at the site, the sun rises over the pillar during the equinox.
Birds appear to have been of particular interest, and for good reason. Tom Schulenberg, a conservation ecologist and ornithologist from the Field Museum's Environmental and Conservation Program, said that Peru has at least 1800 known bird species.
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Monoliths on Waterbird
The mounds, such as this one of a water bird, were marked with monoliths that can still be seen today. A mound with tumbled stone monoliths is visible and was situated on either side of a stairway.
"One monolith appears to be engraved," Benfer said. "This uppermost platform on a mound is called an 'ushnu' in Andean terminology, a place where offerings to the earth are made by priests who monitor the movements of the sun, moon and constellations."
Some of the mounds represent more fantastical shapes, such as this "monster." Benfer says that such monsters were half caiman and half puma. Caimans are semiaquatic reptiles similar to alligators, but with heavily armored stomachs.
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This caiman/puma monster-shaped mound is one of two figures from the 4,000-year-old El Paraiso site in Peru's Chilca Valley. The other, a condor, is partly visible in the upper left. The arrow shows the mound’s alignment in the Milky Way.
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El Paraiso Mounds
In total, Benfer and his team have found 10 giant mounds revealing the shapes of animals. He has also found 150 smaller mounds in fields. Only 10 to 50 of those smaller mounds remain now, however, due to agricultural and building projects destroying them.
Although humans can demolish such mounds, the constructions were clearly built to last. Benfer said, when left alone, they can survive earthquakes as well as basic natural erosion processes.
When studied under different colors and lighting, the mounds also reveal other human-constructed shapes marked by the land. According to Benfer, astronomer priests during prehistoric times may have made observations of the sky from atop the mounds. Having a celestial calendar would have allowed farmers and fishermen to prepare for the year ahead.
The mounds are disappearing rapidly.
"The last decade of enormous economic growth has brought large machinery into valleys where until now, only the horse plow was used on the land," he said. "I have seen a dozen mounds disappear in the last two years."
Benfer hopes that the mounds can be protected as historical sites. "Peruvians need to know the importance of these for their patrimony."
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