The Mayan world has been sleeping buried under vegetation for centuries. A revolutionary technique is revealing its full scale and incredible complexity.
For decades, the two archaeologists and explorers for National Geographic worked in the tropical forests of Central America. They had to endure the crushing heat and humidity and face deadly animals and armed looters to unearth treasures left behind by the ancient Mayans, whose civilization flourished for millennia before being mysteriously swallowed up by the vegetation.
There is therefore something paradoxical in the fact that they made their greatest discovery in front of a computer, in air-conditioned premises, in New Orleans, Louisiana.
When Marcello Canuto and Francisco Estrada-Belli, both of Tulane University, opened the aerial photo of a forested area in northern Guatemala, there was nothing to see on the screen but the treetops. But the photo was taken with a lidar.
This remote sensing device on board an aircraft sends billions of laser pulses to the ground, then measures those that are returned. The small number of pulses passing through the foliage provides enough data to obtain a picture of forest floors.
In just a few clicks, Marcello Canuto removed the vegetation, revealing a 3D image of the terrain. This area had always been assumed to be almost uninhabited, even at the height of the Mayan civilization, more than 1,100 years ago.
Most of Guatemala’s largest cultural heritage sites are found in the Maya Biosphere Reserve, a collection of national parks, wildlife sanctuaries and logging concessions where people exploit timber and other forest products. The reserve, which covers about a fifth of the country, is home to jaguars, scarlet macaws and hundreds of other species of birds, butterflies, reptiles and mammals.
Unlike more arid cradles of civilization like Egypt and Mesopotamia, the rainforests of Central America do not easily give up their secrets. In the mid-19th century, American author John Lloyd Stephens and British artist Frederick Catherwood explored abandoned Mayan cities in Mexico’s Yucatán Peninsula.
Their descriptions and drawings of pyramids and palaces attracted other researchers, but decades of archaeological excavations have only opened a few small windows into the Mayan world.
Why did these ancient populations choose this site, lacking a year-round source of water? Mystery. But, in the Mayan lowlands, the environment is never suitable for human life. The few nutrients contained in the soil are regularly washed away by months of torrential rains, often followed by terrible droughts.
Richard Hansen’s work suggests that population growth in El Mirador was made possible by the transport of fertile land from marshy areas, then spread on terraces built on the hillside. Farmers increased the pH of the soil by adding lime, which produced abundant harvests of corn, squash, beans, peppers, and cotton.
In a region often marked by shortages or excess precipitation, the flow of water was meticulously controlled using canals, dams, reservoirs, and terraces—a large-scale infrastructure that is revealed today.
Tourism could be a source of income. Across the border in southeastern Mexico, Mayan sites such as Chichén Itzá and Palenque attract millions of visitors each year and are among the main drivers of the local economy. Mexico is also building a controversial railway, the “Mayan Train,” to transport summer visitors and cruise passengers from the coast to the remains inland.
The archaeologist hopes that the United States Congress will allocate 72 million dollars (around 67 million euros) to the construction of the line, as well as to eco-responsible accommodation structures. The goal is both to create jobs for Guatemalans and to help stem the flow of economic migrants crowding the U.S. border.
Mark