By Andrew Soergel US News

New geologic evidence suggests periods of extreme drought coincide with the fall of the Mayan civilization.

Mineral deposits found in a Caribbean underwater cave may hold clues to the mysterious downfall of the ancient Mayan civilization.

Belize’s Blue Hole is a massive, almost perfectly circular cave submerged in the Caribbean Sea off the coast of Central America. Rock samples taken from the iconic cave and nearby lagoons suggest the region once dominated by the Mayas experienced a century-long drought from about 800 to 900 A.D., according to Discovery. The 100 years of drought happen to coincide with what historians believe was the downfall of the Mayan people.

The Mayas thrived in the Yucatan Peninsula from about 300 to 700 A.D. They were renowned for developing a written language, an astrological calendar, a series of pyramids and architectural marvels and an effective agricultural production system, according to History.com. But the once mighty civilization reportedly fell into violence and anarchy relatively quickly, eventually vanishing and leaving much open to scholarly debate.

The idea that a drought led to the Mayas’ demise has been on the table since at least 1995, according to Discovery. But the mineral deposits found in and around Belize’s Blue Hole further support the theory.

The Blue Hole and nearby lagoons are surrounded by coral. During particularly rainy periods in history, water from nearby streams and rivers would run over the exposed coral, depositing sediment to the ocean floor below.

“It’s like a big bucket,” said André Droxler, a Rice University professor and co-author of the study, according to LiveScience.

Research teams drilled into sediment deposits inside the Blue Hole to pull out sediment layers that effectively serve as a geologic rainfall record. Ratios of minerals found within the sediment layers give scientists an idea of which years did or did not see heavy rainfall, according to Discovery.

Researchers discovered two significant droughts that coincided with two major periods of decline for the Mayan people. The first, which began around 800 A.D., preceded a Mayan migration towards Chichen Itza in modern-day Mexico, according to NBC News. Researchers speculate that the Mayas may have moved further north as a result of the extreme drought.

The second major drought, which struck between 1000 and 1100 A.D., reportedly lines up with the fall of Chichen Itza.

“When you have major droughts, you start to get famines and unrest,” Droxler said, according to NBC News.

At least the first drought may be attributed to a shift in the intertropical convergence zone, a rainy weather pattern that brings moisture to the world’s tropics. It is speculated that a shift in this system around 800 A.D. may have missed the Yucatan Peninsula entirely, robbing the region of rainwater essential for maintaining a population that at its peak could have included as many as 2 million people, according to LiveScience and History.com.

IMAGE: The “Gran Jaguar” Mayan temple is shown on Dec. 20, 2012, more than 300 miles north of Guatemala City, Guatemala. New geologic research suggests massive droughts contributed to the fall of the Mayan Empire.
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