COLUMBIA, Mo. -- Robert Benfer, a professor emeritus of anthropology at the University of Missouri-Columbia, was rooting around in the Peruvian dirt, looking for evidence of ancient human diet, when he made a startling discovery.

"When we found that first sculpture -- Wow! I was petrified," Benfer said. "I would have been in trouble. You have to have a special permit to excavate something like that."

Benfer and a team of archeologists from the United States and Peru discovered sculptures that indicate flood-plain farmers were tracking the movements of the sun for cultivation purposes 1,000 years earlier than previously thought.

The discovery emerged gradually during excavations in 2004 and 2005. Benfer explained them during formal presentations last month to archaeological conferences.

National Geographic, which has reported some of the findings, helped fund the work.

"It was difficult," Benfer said in an interview. "It took us a long time to figure it out. Archeoastronomy is a sub-discipline of archaeology into which I have never dipped at all."

Benfer and his team were working near Buena Vista, Peru, just north of Lima and about 25 miles inland from the Pacific Coast.

Digging in an area that Benfer calls the "Temple of the Fox," the team found sculptures, carvings and rock formations arranged in such a way to make them suspect that the objects pointed to celestial bodies.

The most significant find was a large clay sculpture of a frowning face flanked by two animals. Benfer calls the find the "Temple of the Fox" because one of the carvings depicted a fox.

"The temple has a sighting device and on the hill above it there's a stone that's been modified in the shape of a face, and they line up like a gun sight to the solstice," Benfer said.

Benfer relied on the help of childhood friend Larry Adkins to determine the significance of the artifacts. Adkins, a retired Rockwell International engineer, teaches astronomy at Cerritos College in Norwalk, Calif.

Adkins determined that the "Temple of the Fox" lines up perfectly with the other stone formations to point to the rising sun on Dec. 21, the summer solstice in the Southern Hemisphere.

That day would mark the start of the planting season.

While it's not unusual to find some relationship with objects on Earth with stars or planets on any particular day, Adkins said "something like the solstice is not there by accident."

"You don't have to stretch here," Adkins said. "This is a sunrise on a very important date. That is very persuasive that this is not by accident."

Adkins also said the sad-faced sculpture faces the sunset on the winter solstice of June 21, which would be the time of harvest.

Benfer believes the sad face depicts Pacha Mamma, an Andean god of fertility. Benfer and his team presented their findings to the Society for American Archaeology in San Juan, Puerto Rico, last month.

Carbon dating of evidence found at the site indicates it was in use about 2200 B.C.

Dave Dearborn, co-editor of the Archeoastronomy Journal, said the finding "would be the oldest known solstice marker in the hemisphere and one of the oldest in the world," according to a report in the Orange County Register.

Benfer said he has other theories about what has been found at the site.

"There are still parts of it that I'm not ready to discuss publicly but I think will be very interesting when we get it all worked out," he said.

Benfer earned his doctorate in anthropology from the University of Texas in 1968 and became an MU professor in 1977.

For most of the past 36 years, he has been conducting research in Peru.

He was studying early civilization's reliance on farming and ocean fishing when he made a discovery that he called the most significant of his life.

The discovery indicates that a priestly political power structure had formed to keep track of farming information that was important to the community.

Benfer said there were indications that looters had come within inches of discovering the sculptures, which are now protected in locked containers.

He plans to return there for more work

"There's lots to speculate on," Benfer said. "We hope to find some more."