Researchers in northern Bolivia have used lidar to identify a series of raised platforms and pyramids. Interwoven by a complex hydrological network, these abandoned sacred sites are relics from a lost Amazonian civilization.
The Casarabe people inhabited what is widely regarded the most fertile farming land in the Llanos de Mojos region of northern Bolivia, in the Amazon basin . Between 500 and 1400 AD, farmers in this lowland tropical savanna built a complex network of cities and towns amidst almost one thousand kilometers of canals and mud causeways. Now, scientists flying lidar scanners have revealed evidence of hitherto undiscovered settlements built by a “lost pre-Hispanic civilization”.
Addressing Past Misinterpretations
Arstechnica explains that history has forgotten what these people called themselves, so the Casarabe people are named after the nearby colonial town. A new study published in the journal Nature claims to resolve a long-standing scientific debate about whether this region could have sustained a large population in ancient times, or not.
Previous surveys in the Llanos de Mojos identified hundreds of mounds. Most of these were concentrated within a 4,500 square kilometer section of plains around the modern Bolivian town of Casarabe. However, 16th century Spanish missionaries only recorded finding small, isolated communities of farmers living in the region.
Study lead author, Heiko Prümers, an archaeologist at the German Archaeological Institute in Bonn, told Live Science that scientists in the 1960s interpreted these earthen mounds “as ruins or natural features.”
Two images of exactly the same area of the Salvatierra site. Left: a photo mosaic from drone footage; right: Lidar image. (Heiko Prümers / DAI)
Mundane Mounds Become Ceremonial Pyramids With Lidar
Penetrating the dense Amazonian vegetation with airborne lidar, the team of researchers have successfully identified the nature of several unknown mounds in areas now known as Cotoca and Landívar. They turned out to not be natural piles of dirt, but vast ceremonial centers with “huge, raised platforms of earth, topped by enormous pyramids,” according to the study.
The new paper describes two large Casarabe settlements that stood central in a network of roads, causeways, reservoirs and canals. Contrary to Spanish accounts, according to Prümers, this region was “very densely populated in pre-Hispanic times.” The archaeology, it turns out, is so thick in this region that earlier scientists thought the proliferation of mounds must have been geological! Prümers concluded that Casarabe people had instituted “a low-density tropical urbanism across a vast area.”
Top view of the lidar sensor mounted in the helicopter while scanning the tropical forest. (Jose Iriarte DAI / CC BY-NC-ND )
Finding An Amazonian Civilization From The Sky
Prümers said “24 ceremonial sites” have now been identified in the area. No less than nine of these were found for the first time in this latest lidar study. While the two major sites at Cotoca and Landívar were known about previously, “their true extent” has only now been revealed by lidar, said Prümers. It was revealed that these two mega-settlements were joined by a complex matrix of roads and causeways forming loose concentric circles.
Extensive waterways radiated out in all directions from the two major settlements which the researchers said represented “a major investment in landscape management and labor mobilization.” Prümers said this complex- hydrological system perhaps controlled seasonal floods and enabled the farming of maize and other crops in higher areas, while fish might have been farmed in lower flooded parts of the landscape.
All Good Things Must Come To An End
The researchers also determined that the ritualistic platforms and ceremonial pyramids were oriented facing the north-northwest. The scientists said this was the same direction as most of the Casarabe burials that have been found. This predominant astronomical alignment, along with the ceremonial pyramid structures suggests a well-developed cosmovision, or community wide religious beliefs
Whatever spiritual practices may have gone on here certainly didn’t work, for the study concludes
“water scarcity” brought about the demise of the Casarabe civilization around 1400 AD. This collapse occurred more than a century before the Spanish conquistadors arrived. Thus, the pyramids erected in the honor of ancient sky gods, it would seem, had lost their life blood through droughts a long time before the dragons arrived to scorch their land.
Top image: Screenshot from a 3D animation of the Crotoca site where evidence of the lost Amazonian civilization has been found. Source: Heiko Prümers DAI / CC BY-NC-ND
By Ashley Cowie