SAO PAULO, Brazil(AP) A grouping of granite blocks along a grassy Amazon hilltop may be the vestiges of a centuries-old astronomical observatory _ a find archaeologists say indicates early rainforest inhabitants were more sophisticated than previously believed.
The 127 blocks, some as high as 9 feet tall, are spaced at regular intervals around the hill, like a crown 100 feet in diameter.
On the shortest day of the year _ Dec. 21 _ the shadow of one of the blocks, which is set at an angle, disappears.
"It is this block's alignment with the winter solstice that leads us to believe the site was once an astronomical observatory," said Mariana Petry Cabral, an archaeologist at the Amapa State Scientific and Technical Research Institute. "We may be also looking at the remnants of a sophisticated culture."
Scientists not involved in the discovery said it could prove valuable to understanding pre-Columbian societies in the Amazon.
"No one has ever described something like this before. This is an extremely novel find _ a one of a kind type of thing," said Michael Heckenberger of the University of Florida's Department of Anthropology.
"The traditional image is that some time thousands of years ago small groups of tropical forest horticulturists arrived in the area and they never changed _ (that) what we see today is just like it was 3,000 years ago," Heckenberger said. "This is one more thing that suggests that through the past thousands of years, societies have changed quite a lot."
