Takeshi Inomata: Investigating Droughts and Maya Collapse

Takeshi Inomata, a professor of anthropology at the University of Arizona, writes from Guatemala, where he and Daniela Triadan are excavating the Maya site of Ceibal.

An important component of our research is the study of the past environment and climate changes. A team of Japanese geologists and plant scientists addresses this by analyzing lake sediments as part of the project financed by the Japanese Ministry of Education, Culture, Sports, Science and Technology and directed by Kazuo Aoyama.

In contrast to archaeologists, who usually specialize in specific geographic regions, those researchers are global travelers. They have been taking lake cores from Japan, China, Cambodia, Bali, Easter Island, Egypt and Peru. The team is known for its uncanny ability to find annual varves and for its innovative analysis. Under specific conditions of seasonal change, lake hydrology and the anoxic water that prevents bottom-dwelling critters from disturbing sediments, thin laminations of deposits may form yearly in lake bottoms. These annual varves are time capsules of environmental data. Through the analysis of geochemistry, isotopes, pollens, diatoms (a group of algae) and other remains in each layer, scholars can trace changes in precipitation, vegetation, agricultural practice, erosion rates, volcanic eruptions, etc., in a yearly resolution.

By collaborating with these natural scientists, we try to examine the effects of environmental changes on social processes, as well as human impact on the environment. A particularly intriguing question is the relation between droughts and drastic social changes. Around the ninth century A.D., many lowland Maya centers were abandoned. This is the phenomenon generally called the Classic Maya collapse. Recent studies of lake cores from the northern Maya lowlands by other scholars have shown possible evidence of droughts during this period....