When the Rains Never Failed: Rethinking Collapse in the Maya Southwest

A Landscape That Should Have Thrived

For decades, the story of the Classic Maya decline has been told with a climate plotline at its center. Monumental cities withered, dynasties crumbled, and populations thinned just as severe drought gripped parts of the Maya lowlands. The timing aligned so neatly that the drought hypothesis became a kind of shorthand for collapse.

Benjamin Gwinneth crossing the Polochic River in northern Guatemala. Credit: Jonathan Obrist Farner

Yet on the forested edges of the southwestern lowlands, at a lake called Laguna Itzan, a different picture emerges. Sediment cores pulled from its basin do not tell a story of vanishing rainfall. Instead, they preserve a steady record of moisture during the very centuries when nearby cities faltered.

Benjamin Gwinneth observes a core of lacustrine sediments taken from Lake Izabal, Guatemala. Credit: Jonathan Obrist Farner

This puzzle sits at the heart of a new study in Biogeosciences,¹ offering an unsettling reminder that environments and societies rarely fit our simplest narratives.

“Environmental stability does not equate to social security,” says Dr. Liora Kent, an environmental archaeologist at the University of Arizona. “A society can be thriving ecologically but still collapse through its ties to wider regional networks.”