It’s surprising how quickly nature can reclaim the earth, particularly in the jungles and rainforests of the Earth’s middle latitudes. In those areas we have often been limited to exploring the ruins of past civilizations that are only obvious by their size; they stick up.
Occasionally Archeologists have been lucky enough to discover a few artifacts such as pottery shards or tools that would lead them to dig a little deeper. Many early American inhabitants lived in caves or other natural shelters as they migrated down the North American continent and into Central America. The caves and outcroppings would preserve what was left behind and subsequent visitors would deposit layer after layer of debris; all conveniently left behind for us to dig up. However, in Central America and northern South America, nature reclaims its own.
In the past, Archeologists would map out a grid over a promising area surrounding something that “stuck up” and go in search of other artifacts or structures that might shed light on the what had happened there. Sometimes they would get lucky. Many times, the forest was just too dense and further exploration would do too much harm without any promise of success. So, studies often stopped before too much damage was done to the environment. Even if something significant was found the dig often ended early to preserve the forest.
More recently, new methods have revealed that we have a lot to learn about past human activities in Central and South America. In many areas the tropical rain forest has reclaimed the land and covered over thousands of square miles of roads, canals, and buildings.
Scientists are now using a system called LiDAR (Light Detection and Ranging) to reveal a much larger, more complex, and interconnected pre-Columbian civilization than specialists in Mayan history had ever imagined.
LiDAR uses pulses of laser light to map an area. It measures the time it takes for the pulses to reflect off an object and return. It uses this information in combination with signal wavelength to make a 3-D image of the target. The term LiDAR is an acronym for light detection and ranging. Originally developed for the military It is now used across a range of sciences including geography, geology, seismology, oceanography, and archaeology, to name a few.
LiDARs can be built using infrared to ultraviolet light lasers. The application determines which light source is used. They can scan through forests, jungles, sand, and water. A LiDAR using a green laser can even be used to map some parts of the ocean floor; revealing lost ships or coastal cities now sunken beneath the waves. The LiDAR laser beam is scanned at many different angles over an area from the air; while a plane or helicopter flies a grid pattern over a location. The strength and time delay of the reflected signal are recorded and combined with precision GPS position data to create a 3D image of the area. Lasers can penetrate all the way to the floor of the forest through the smallest of openings in the vegetation and can even pass through some of the vegetation, reflecting back to the LiDAR source.
The 3D maps reveal the basic geometrical shapes of buildings, roads, canals, and plazas. Even after LiDAR reveals a structure, it may be so hidden that it might not be visible standing right next to it, particularly in the dense foliage of the rain forest. Recently LiDAR mapping has found that the Mayan civilization was much larger that any one previously thought.
In the past Archeologists estimated a population of 5 million people at the height of the Mayan civilization. They now believe the population could have been as high as 15 million people spread out over an 800 square mile or larger region. The area is covered by roads, causeways, complex irrigation systems, canals, dikes, and reservoirs.
Over 50,000 pre-Columbian structures have been mapped. Surprisingly there were also many defensive structures including wall, ramparts, terraces and fortresses, indicating that the Mayan were concerned with warfare over a much longer period of time than previously thought. Who were they fighting? The PACUNAM LiDAR Initiative is a three-year project that is using LIDAR to map 5,000 square miles of Guatemala’s lowlands. We have a lot to learn about the pre-Columbian world of the Mayan.
LIDAR is being used around the world to reveal human activity where there has never been any hint of civilization before. For instance, it turns out that Angor Wat was the center of a vast civilization, much larger than ever suspected.
Do you want to learn more? Go to https://www.ancient-origins.net/lidar
There you can read about Lost African Cities, the 2,000-year-old Dwellings of Iron Age Hill Fort, Angkor Wat, the largest ancient city of ancient times, and many other wonders revealed by LIDAR.
By Timothy Shively, February 21, 2019
Food For Thought.
How far would have the Mayan civilization have gone if they had had large draft animals? Remember that at the time of the Mayan everything had to be done by manpower.
https://en.wikipedia.org/wiki/Lidar
https://news.nationalgeographic.com/2018/02/maya-laser-lidar-guatemala-pacunam/
https://www.historyonthenet.com/rise-and-fall-of-maya-civilization-over-3000-years
https://news.nationalgeographic.com/2018/02/maya-laser-lidar-guatemala-pacunam/
https://news.nationalgeographic.com/2018/02/maya-laser-lidar-guatemala-pacunam/