A researcher retraces an ancient Costa Rican footpath under study by CU-Boulder and NASA researchers using satellite and video-game technology.
(Photo courtesy of
Payson Sheets, CU-Boulder)
Researchers Track Movements Of Ancient Central Americans Using Satellites,
Video-game Technology
ScienceDaily
(Jan. 4, 2007) —
Satellite imagery meshed with video-game technology is allowing University of Colorado at Boulder and NASA researchers to virtually "fly" along footpaths used by Central Americans 2,000 years ago on spiritual pilgrimages
to ancestral cemeteries.
The effort has allowed researchers to trace the movements of ancient people in the Arenal region of present-day Costa Rica, who used single-file paths to navigate rugged terrain between small villages and cemeteries over the centuries, said CU-Boulder Professor Payson Sheets. The repeated use of the footpaths caused erosion resulting in narrow trenches in the landscape up to 10 feet deep.
The evidence now indicates people re-used the same processional routes for more than 1,000 years, returning
to them despite periodic abandonment of villages caused by recurring violent eruptions of the nearby Arenal Volcano, he said. Sheets gave a presentation on the subject at the 2nd International Conference on Remote Sensing in Archaeology held in Rome from Dec. 4 to Dec. 7.
The researchers have traced one processional path from a village on the Caribbean side of northern Costa Rica over the Continental Divide to a cemetery about 10 miles away using infrared satellite images that indicated characteristic signatures of plant growth, he said. The eroded footpaths -- some virtually invisible to observers on the ground -- collect water that stimulates increased root growth in the vegetation that appears in the images as reddish lines, said Sheets.
"This project has been a huge surprise," said Sheets. "Modern technology has allowed for the discovery and study of 2,000-year-old footpaths in the tropics where the ground is covered by thick vegetation and multiple layers of ash from prehistoric volcanic eruptions."
Software originally developed for video games lets the researchers fly along the footpaths at various altitudes, directions and tilt angles and zoom in on particular landscape features, said Sheets. The team has been able
to pinpoint sources of stone used to construct elaborate graves and to confirm springs used for water during ritualistic feasting ceremonies at the cemeteries that lasted for days on end.
