Understanding civilizations of the past and how they emerge and eventually falter is a primary research focus of archaeological investigations because these provocative data sets offer critical insights into long-term human behavior patterns, especially in regard to land use practices and sustainable environmental interactions. The ancient Maya serve as an intriguing example of this research focus, yet the details of their spectacular emergence in a tropical forest environment followed by their eventual demise have remained enigmatic. Tikal, one of the foremost of the ancient Maya cities, plays a central role in this discussion because of its sharp population decline followed by abandonment during the late 9th century CE. Our results, based on geochemical and molecular genetic assays on sediments from four of the main reservoirs, reveal that two of the largest reservoirs at Tikal, essential for the survival of the city during the dry seasons, were contaminated with high levels of mercury, phosphate and cyanobacteria known to produce deadly toxins. Our observations demonstrate severe pollution problems at a time when episodes of climatic aridity were prevalent. This combination of catastrophic events clearly threatened the sustainability of the city and likely contributed to its abandonment.
Bibliographical noteFunding Information:
We thank Eric Ponciano of the Guatemalan Ministry of Culture and Sports, Juan Carlos Pérez Calderón, Director General of the Institute of Anthropology and History of Guatemala (IDAEH), Mónica Urquizú, Head of the Department of Prehispanic and Colonial Monuments at IDAEH and the administrators of Tikal National Park, i.e., Armando Guillén, Elmer Tun and Fredy Sosa, for their support and guidance during our two field seasons (2009 and 2010) at Tikal. We also thank Jeff Havig, Rachel Wright, Jane Rosenthal, Sherman Bradley and Suman Pradhan for their preliminary chemical and microbiological efforts. Cory Perfetta and Linnea Lentz prepared the figures. This research was supported by grants from the U.S. National Science Foundation (BCS-0810118 and BCS-1642547), the Wenner-Gren Foundation (7799), the Alphawood Foundation and the University of Cincinnati. The views expressed in this article are those of the author[s] and do not necessarily reflect the views or policies of the U.S. Environmental Protection Agency (EPA). Any mention of trade names, products, or services does not imply an endorsement by the U.S. Government or the EPA. The EPA does not endorse any commercial products, services, or enterprises.
PubMed: MeSH publication types
- Journal Article
- Research Support, U.S. Gov't, Non-P.H.S.
- Research Support, Non-U.S. Gov't