The ancient Mayan civilization, which developed a sophisticated culture in the Central American rainforests, vanished mysteriously a thousand years ago.  Now, an international team of anthropologists, archeologists, chemists and climatologists says it has identified the cause of the Mayan collapse: climate change.

To create a weather record for the past 2,000 years, the scientists analyzed a natural mineral formation called a stalagmite from a cave in Belize, using oxygen-isotope dating to determine how much rain fell on the region over the centuries. Stalagmites build up incrementally, like tree rings, as water drips through the cave ceiling, preserving an accurate climate record.