Image analysis guided by AI revealed a 2,000-year-old picture dug into the Peruvian desert.
What happened: Researchers analyzing aerial imagery shot over Peru found a pattern that looks like a three-horned humanoid holding a staff. The figure is roughly 16 feet across and may have served as a waypoint along an ancient path. Known as geoglyphs, such pictures were created by people who predated the arrival of Columbus by 1500 years. The sprawling patterns are visible only from higher elevations.
How it works: Using manual methods, researchers at Yamagata University found more than 100 geoglyphs in satellite photos and other imagery from the region of southeastern Peru called the Nazca Pampa. But they had collected too much data from surrounding areas to search manually. So they teamed with IBM Japan to feed the data into PAIRS Geoscope, a cloud-based deep learning system that analyzes geospatial data. This video describes the project.
- Training Geoscope to find the images presented several challenges. The geoglyphs range in size from tens of feet to nearly a quarter-mile across. They depict birds, humans, reptiles, and abstract shapes. Some are drawn in thin lines, others are filled-in shapes. The system had to learn not to be fooled by river beds and roads, which can trace superficially similar shapes.
- The team trained the system on photos, lidar, and GIS data describing confirmed geoglyphs.
- The model selected more than 500 candidates within a three-square-mile test range. The team reviewed the candidates manually. They chose the most promising one and confirmed it in the field.
Behind the news: The people who created the Nazca geoglyphs lived on the arid Peruvian plains, or pampas. They made these shapes by removing the top layer of pebbles to expose lighter-colored clay roughly six inches below. Conquistadors noted the geoglyphs in their travelogues as far back as the 1500s, but it wasn’t until the 1940s that researchers began studying their origin and purpose.
Why it matters: Remote sensing techniques have spurred a renaissance in archaeology. They’ve helped uncover Mayan pyramids on Mexico’s Yucatan peninsula and abandoned cities in the Cambodian jungle.
We’re thinking: Who wants to team with us to create a massive deeplearning.ai geoglyph to confuse and amuse future generations?