In one of the most remarkable developments in Maya archaeology in decades, the PACUNAM LiDAR (“Light Detection and Ranging”) initiative has revealed the existence of a massive number of Maya structures previously obscured by northern Guatemalan forest. As reported by Tom Clyne of National Geographic, some 60,000 pyramids, roads (including raised highways), family dwellings, agricultural structures, and defensive fortifications have been digitally uncovered using aerial wavelength-measuring technology. The size and complexity of the exposed structures offer an exciting challenge to prevailing knowledge about the Maya population in the region during the Classic period (AD 250–900).
Prior knowledge of ancient settlements in the Maya lowlands was obtained via ground excavation, which suggested that Maya urban centers were isolated and dispersed. LiDAR data paints a very different picture. “The first use of LiDAR in archaeology was in Costa Rica in 1985, on my project,” archaeologist Payson Sheets told UPC. “Then it was only one laser gun, so [it] functioned as a profiler. It now covers large areas, and is spectacular, actually revolutionary, especially in tropical rainforests.” Gathered by reflecting laser pulses off the ground (in this case, some 810 square miles of presently unpopulated territory in the Maya Biosphere Reserve) and measuring the returning wavelengths, LiDAR data forms a three-dimensional map of the stone elements of the landscape that lie hidden beneath the trees—elements that we now know to be far denser and more closely connected than previously supposed, some in areas long believed by archaeologists to be uninhabitable.
The landscape as seen by the naked eye (left) and via LiDAR technology (right). Courtesy National Geographic/Wild Blue Media (images as featured in Lost Treasures of the Maya Snake Kings, more information about which can be found at www.natgeotv.com).
Thomas Garrison (coeditor of UPC’s upcoming volume An Inconstant Landscape: The Maya Kingdom of El Zotz, Guatemala) served on the archaeological advisory committee for the PACUNAM LiDAR initiative. He commented to Live Science on what this new discovery means for current population estimates of the ancient Maya—revision upward by “multiple factors”—and for our understanding of ancient Maya agricultural practices, which sustained a sizable population without the use of destructive modern slash-and-burn techniques. Tulane archaeologist Francisco Estrada-Belli told National Geographic that population estimates of the Classic Maya in the area could now reasonably be revised from five million people to ten or fifteen million.
The PACUNAM LiDAR initiative is still in its first phase and set to explore some 5,000 square miles of the Guatemalan lowlands over the next three years. “What the PACUNAM LiDAR Initiative shows us,” Thomas Garrison told UPC, “is that looking at Maya landscapes from a regional perspective (in this case 2,100 square kilometers) is going to tell us so much about the civilization as a whole, in a way that will help put kingdoms like El Zotz into a broader perspective. All of the new ancient settlements and features revealed by this survey mean that archaeology and cultural heritage management will thrive in Guatemala for years to come."
For more information, including illustrations of the findings of the PACUNAM LiDAR initiative, check out the National Geographic and Live Science reports on the survey, featuring commentary from Thomas Garrison, Lisa Lucero, Marcello Canuto, Francisco Estrada-Belli, Payson Sheets (coeditor of UPC’s Surviving Sudden Environmental Change: Answers from Archaeology), and other experts.