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May 10, 2012 Volume 33, No. 31

Professor emeritus discovers animal-shaped mounds in Peru valleys

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ANCIENT ASTRONOMERS Robert Benfer, an MU professor emeritus of anthropology shown here last December in Peru, used Google Earth Pro from his Columbia home to discover mounds that resembled animals when viewed from the sky. His research suggests that astronomy was important to a culture that flourished 4,000 years ago. Photo courtesy of Robert Benfer


Benfer’s discoveries suggest advanced culture 4,000 years ago in Peru

Robert Benfer, an MU professor emeritus of anthropology, has made important archaeological discoveries during his decades of field research in South America.

But his latest eureka moment came not in the hot dust of a remote Peruvian valley, but from the comfort of his Columbia home.

Benfer was perusing on Google Earth Pro the aerial geography of Peru’s Casma and Chillon valleys, which contain ruins of a sophisticated but mysterious culture that existed some 4,000 years ago. He zoomed in on mounds up to 1,300 feet long sprinkled with structures and relics made by an ancient people, often called Andeans.

From that vantage point, Benfer noticed that two mounds outlined shapes, something impossible to glean from the ground. “These are animal figures,” he remembers thinking. “There can’t be just two.”

Benfer has since identified eight giant effigy mounds and dozens of smaller ones that resemble whales, condors, snakes, birds and the mythical monstruo, a composite of long-clawed creatures. The effigy mounds are similar to Andean animal carvings and constellations in the South American zodiac. 

To determine the precision of correspondence between the mounds and the night sky, Benfer and Larry Adkins, an astronomy professor at Cerritos College in California, turned to archaeostronomy, the science of ancient astronomy. Using the software “Starry Night,” Benfer and Adkins rewound the starry sky to how it looked to Peruvians 4,000 years ago.

In his article published this spring at the archaeological online journal Antiquity, Benfer points out that the mounds not only represent the Andean zodiac. They also align with the stars. Benfer contends that there are astronomical orientations at every giant mound. To someone standing in a nearby temple four millennia ago, the charcoal eye of the condor mound would have lined up with the Milky Way, and the monstruo mound would’ve directed the eye to the June summer solstice.

This is not happenstance. Platforms of earth and rock appear to have been constructed at just the right angle to achieve a marriage, as it were, between sky and earth.

Benfer’s mound theory dovetails with his 2006 discovery of stone-made astronomical devices in the same coastal region. One was atop a 33-foot pyramid. Taken together, the discoveries suggest that the Andeans, who predate the better-known Mayans of Mexico and Central America by thousands of years, were savvy astronomers.

Unlike the Mayans, the Andeans left no writings, so scientists can only speculate why these ancient Peruvians built the mounds. The consensus among scholars is that the mounds served two purposes — one practical and the other supernatural.

The Andeans, who were agricultural people, probably tracked the stars to know when to plant and harvest, Benfer said. The stars were their “agriculture calendar in the sky.”

To ensure a good crop, they also made offerings from atop the mounds to the forces they believed controlled the weather and the seasons, Benfer said. 

This month, Benfer will submit an in-depth article on the coastal valley effigy mounds for publication in the print version of Antiquity. And this summer he’ll be back in Peru. He plans to venture farther east on the Casma and Chillon valleys to investigate other intriguing mounds he spotted on Google Earth Pro.