In the Late Bronze Age, a thriving society near present-day Tel Aviv and far beyond suddenly fell apart, and researchers have long been stumped as to the precise cause—until now. The explanation for the crisis lies in fossilized pollen, which remains stable for millennia and points the finger of blame, in this case, at drought. To make their findings, researchers plunged into the sediment under the Sea of Galilee, where pollen had been "driven by wind and river-streams ... [and become] embedded," a researcher tells the Jewish Press. They drilled 65 feet downward and pulled out 60 feet of sediment cores, the New York Times reports. Near the Dead Sea, they obtained further cores.
Over the course of three years, the experts investigated the pollen grains trapped in the cores, looking at samples from every 40 years between 3,500 BC and 500 BC. (The Times calls those 40-year increments "the highest resolution yet in this region.") They discovered that populations of Mediterranean oaks and pines, as well as olive trees, saw a sudden and fairly drastic decrease in the Late Bronze Age, indicating a series of droughts, specifically between 1250 and 1100 BC. The researchers also discussed what came next: a wet period that heralded the dawn of Biblical kingdoms. "Understanding climate is key to understanding history," says one of the researchers. (In related news, 245 million-year-old grains of pollen helped researchers solve an "abominable mystery.")