The Amazon was still densely populated in some places. This is evidenced by 3D scans that German and British researchers conducted from a helicopter. 28 towns and villages appeared in the Bolivian part of the rainforest.
The research further undermines the view that the Amazon was previously largely uninhabited. The dense vegetation of the rainforest could simply have made building crowded cities impossible, it has been argued since the 1960s. Since then, scholars have increasingly questioned this, in part because Discovery ancient agriculture. This new research appeared Wednesday in the scientific journal temper nature, showing for the first time a network of cities in the Bolivian Amazon. The oldest cities, the size of some medieval European cities, date back to the 5th century BC.
Twenty years ago, the lead German researcher, archaeologist Heiko Brommers, began surveying hundreds of square kilometers of savannah. The search for traces of an ancient civilization in the Amazon is difficult, because now only a few hills and ditches remain. Stones were not in use at that time, and earth and wood were the main building materials.
However, Brommers and his team, in cooperation with the Bolivian government, have come across indications of urban development. After three years of measurement, they mapped nearly an acre of land, revealing hills, canals, and landscaped roads: a city that predates Spanish colonization.
light reflections
However, Brommers wanted to prove that the entire area he was looking at, an area of about two hundred square kilometers, was structurally built with towns and villages. He used a relatively new technique in archaeology called “lidar”. Just as radar can visualize the environment through reflected sound waves, lidar does so with light (that’s what the “L” stands for). Archaeologists flew in a helicopter over the Bolivian Amazon and shone special rays of light on the ground. These rays of light bounced off the surface for the helicopter to retrieve.
Using the time traveled by the light rays, the researchers measured how far all the structures on Earth and the vegetation above were, and provided a 3-D map of the savanna. They filtered vegetation from the 3D map. After the “digital deforestation”, the landmarks of the cities of the past became visible. Highly valuable from an archaeological standpoint, but also environmentally sound: “We cut down trees with our calculators, not axes,” says Brommers.
pyramid 20 meters
It is clear that the structures that appeared were man-made: in the largest city, two kilometers in length and width, there was a pyramid about 20 meters high. Around it, researchers found U-shaped structures. Similar to those found in the Andes Mountains that are known to have performed religious ceremonial functions. Altogether it was surrounded by three ring-shaped defensive walls, which show that the city had grown over the centuries, from about 500 to 1400. Finally, Brommers and his team encountered roads, canals, and large basins of water.
The team visited these towns and villages on the ground. Researchers excavated at two sites and found processed ceramics and bones: “everyday objects that prove they were indeed settlements,” Brommers says.
Martin Berger, an archaeologist at Leiden University, described the study as “brilliant and compelling.” According to him, this “ends fifty years of debate about the inhabitation of the Amazon”, and shows that there really is a complex culture. The exact form of that culture is still unknown. This requires more research.
It is still not known exactly how many people lived in Latin America before the arrival of the Europeans. That’s because the diseases that settlers brought with them affected the indigenous population. As a result, little has been recorded about the peoples.
