The ancient Maya of the once bustling city of Tikal built sophisticated water filters using natural materials imported from miles away, according to the University of Cincinnati.
The researchers discovered evidence of a filter system in the Corrientel reservoir, an important source of drinking water for the ancient Maya in what is now northern Guatemala.
A multidisciplinary team of anthropologists, geographers and biologists from the University of Cincinnati identified crystalline quartz and zeolite that had been imported from several kilometers into the city. The quartz found in coarse sand together with zeolite, a crystalline compound of silicon and aluminum, create a natural molecular sieve. Both minerals are used in modern water filtration.
Filters would have removed harmful microbes, nitrogen-rich compounds, heavy metals like mercury, and other toxins from the water , according to Kenneth Barnett Tankersley, an associate professor of anthropology and lead author of the study. The interesting thing is that this system would still be effective today and the Mayans discovered it more than 2,000 years ago .
The Mayans created this water filtration system almost 2,000 years before similar systems were used in Europe, making it one of the oldest water treatment systems of its kind in the world , according to Tankersley.
The researchers traced the zeolite and quartz to the rugged ridges surrounding the Bajo de Azúcar, about 29 kilometers northeast of Tikal. They used X-ray diffraction analysis to identify zeolite and crystalline quartz in the reservoir sediments.
For the ancient Maya, finding ways to collect and store clean water was of critical importance. Tikal and other Mayan cities were built on porous limestone that made access to drinking water difficult for much of the year during seasonal droughts.
University of California geography professor and co-author Nicholas Dunning, who has studied ancient civilizations for most of his career, found a likely source of quartz and zeolite about 10 years ago while conducting fieldwork in Guatemala.
It was an exposed and eroded volcanic tuff of quartz and zeolite grains. It was water that flowed at a good rate , He said. The workers filled their water bottles with it. It was famous locally for how clean and sweet the water was .
Dunning took samples of the material. Researchers later determined that the quartz and zeolite closely matched minerals found at Tikal.
It was probably through very clever empirical observation that the ancient Maya saw that this particular material was associated with clean water and made some effort to bring it back Dunning said.
University of California anthropology professor emeritus Vernon Scarborough, another co-author, said most research on ancient water management has tried to explain how civilizations conserved, harvested or diverted water.
The quality of drinking water has remained difficult to address Scarborough said. This study by our UC team has opened up the research agenda by identifying the quality of a water source and how it might have been established and maintained.
Of course, reconstructing the lives, habits, and motivations of a civilization from 1,000 years ago is difficult. We don't have absolute evidence, but we do have strong circumstantial evidence Dunning said. Our explanation makes logical sense .
This is what you have to do as an archaeologist said biologist and co-author David Lentz. You have to put together a puzzle with some missing pieces. Lentz said the filtration system would have protected the ancient Maya from harmful cyanobacteria and other toxins that could have otherwise made people who drank from the reservoir sick. The ancient Mayans discovered that this material produced pools of clear water he said.
Complex water filtration systems have been seen in other ancient civilizations, from Greece to Egypt to South Asia, but this is the first time it has been seen in the ancient New World, Tankersley said.
The ancient Mayans lived in a tropical environment and had to be innovative. This is a remarkable innovation according to Tankersley. Many people consider that the Native Americans of the Western Hemisphere do not have the same engineering or technological muscle as places like Greece, Rome, India or China. But when it comes to water management, the Mayans were millennia ahead.