Topic: Environment

Scientists found no drought at a key Maya site. Instead, they discovered clues about human and environmental history.

Between 750 and 900 CE, the Maya civilization in Central America experienced a significant decline in population and power. For years, researchers believed that repeated periods of severe drought were the main cause of this collapse. However, new findings suggest that the story may be more complicated than just a climate crisis.

Benjamin Gwinneth, a geography professor at Université de Montréal, has been studying environmental change and its impact on the Maya civilization. He analyzed sediment cores from Laguna Itzan, a nearby lake in present-day Guatemala, to piece together a long-term record of environmental conditions and human activity in the region.

The results show no signs of drought at Itzan during the period when the Maya population declined. Despite this, the local population collapsed around the same time as communities in other parts of Guatemala and Mexico that did experience drought. So what caused the decline? To answer this question, Gwinneth's team examined three types of geochemical markers preserved in lakebed sediments.

These markers included polycyclic aromatic hydrocarbons, which indicate the intensity of slash-and-burn fires; leaf waxes, which reflect vegetation and rainfall patterns; and fecal stanols, which help estimate population size. By analyzing these indicators, the team tracked changes in population, farming practices, and climate over thousands of years.

The data revealed that the first permanent settlements appeared 3,200 years ago. There were slash-and-burn fires and an increase in population during this time. The Maya used fire extensively during the Preclassic period, between 3,500 and 2,000 years ago, to clear forests and grow crops on fertile ashes.

During the Classic period, between 1,600 and 1,000 years ago, the data show a major shift. Population density increased significantly, yet the use of fire dropped sharply. This probably means that most of the land had been cleared, which could have led to a change in agricultural strategy.

The evidence points to more intensive farming methods, such as ridge and furrow ploughing to limit erosion and more focused gardening practices. Fire was no longer an important component of their farming practices. This transformation reflects gradual urbanization and suggests that the Maya were changing agricultural strategies to feed a growing population.

These findings match what researchers already understand about the Maya at their height. Their society was highly organized, urbanized, and supported by advanced agricultural techniques tailored to local conditions.

Another key piece of evidence comes from hydrogen isotope analysis, which helps reconstruct past rainfall patterns. Unlike sites farther north that experienced drought, Itzan appears to have maintained a stable climate.

This finding is especially important because some scholars have proposed that the Maya collapse began in the southwestern lowlands, where Itzan is located. If drought did not affect this area, it likely was not the initial trigger.

Why It Matters

Understanding the decline of the Maya civilization can help us better appreciate the complexity and interconnectedness of human societies with their environments.

Key Facts

• The Maya civilization experienced a significant decline in population and power between 750 and 900 CE.
• New findings suggest that drought was not the main cause of this collapse, but rather a combination of factors including changes in farming practices and environmental conditions.
• Benjamin Gwinneth's team analyzed sediment cores from Laguna Itzan to piece together a long-term record of environmental conditions and human activity in the region.
• The data revealed that the first permanent settlements appeared 3,200 years ago, with an increase in population and slash-and-burn fires during this time.
• During the Classic period, population density increased significantly, yet the use of fire dropped sharply, suggesting a change in agricultural strategy.

Key Terms

Slash-and-burn agriculture

A farming practice that involves clearing forests and growing crops on fertile ashes

Implications

Understanding the decline of the Maya civilization can help us better appreciate the complexity and interconnectedness of human societies with their environments.