The Mayan civilization is known to be one of the most sophisticated civilizations in America prior to the Spanish colonization of the region. Its sudden collapse sometime between the 8th and 9th century is also one of the mysteries that baffled experts and which has given rise to a number of theories including overhunting, deforestation and even alien invasion.
A new research, however, supported a theory that attributed long-term drought to the Mayans abandoning their cities. André Droxler, an Earth scientist at Rice University, and colleagues examined the chemical composition of the sediment cores that were taken from the Great Blue Hole, a large sinkhole in Belize, and from nearby lagoons to look for signs that could support the postulation that dry spell helped drive the collapse of the ancient civilization known for its relatively advanced mathematical, writing and astronomical systems as well as art and architecture.
Analysis of sediment cores provides researchers with timeline of past events that could shed light on historical climate, among others. Droxler and colleagues, in particular, focused on analyzing the ratio of titanium to aluminum in the samples because low ratios indicate periods where there were fewer rainfalls.
The researchers found that an extreme drought occurred during the period associated with the disintegration of the Mesoamerican civilization. The collapse of the Mayan civilization Between A.D. 800 and A.D. 1000 coincided with the time frame when there were only between one and two tropical cyclones every two decades, which is lower when compared with the usual five or six.
The Mayans then moved North when the rains returned relocating at Chichen Itza but between A.D. 1000 and A.D. 1100, the height of the Little Ice Age, the researchers' analysis also showed that another major dry spell occurred and this coincided with the fall of Chichen Itza strengthening the theory that drought influenced the decline of the Mayan culture.
Droxler acknowledged that their study is not the first to associate drought with the fall of the Mayan culture but the researcher said that it strengthens the theory given that their data were from several spots in the region that were central to the Mayan civilization.
A study that examined a 2,000-year-old stalagmite from a cave located in Belize, for instance, offered evidence that significantly reduced rainfall occurred during the periods of the culture's decline but the study is based on data from just one cave.