The collapse of Classic Maya civilisation linked to drought

The Classic Maya culture thrived in rainy times and then collapsed in turmoil as the weather turned to drought, according to new research. An international project including Durham University and led by researchers from Pennsylvania State University, USA, and ETH Zurich, Switzerland, has created a precisely-dated record of rainfall from cave deposits in the Classic Maya region, and compared it to a 'war index' of hostile events recorded on stone monuments. The research has enabled the team to create a unique historical timeline linking climate and culture in unprecedented detail. The war index is based on how often certain keywords occurred in Mayan inscriptions on carved stone monuments, and the researchers were able to chart how increases in war and unrest were associated with periods of drought. The new datasets provide a unique insight into how a civilisation prospered and developed, expanding into large cities, during a period of favourable climate and then collapsed following climate change between AD 660 and 1100. Maya rulers commissioned monuments to record events and the research team found the frequency of texts carved on stone monuments pointing to status rivalry, war and strategic alliances increased significantly between AD 660 and 900, during the drying trend. The findings are published in the journal Science.