Ancient pollen and charcoal are giving scientists clues about the natural disasters that plagued ancient Egypt.
Researchers from the US Geological Survey (USGS) have found traces of both pollen and charcoal in buried sediments in the Nile Delta, which may shed light on the history of the region.
The most signifcant finding, reported Planet Save, includes evidence of a huge drought 4200 years ago that was the likely cause of the fall of Egypt's old kingdom when the Pyramids were built.
“Even the mighty builders of the ancient pyramids more than 4,000 years ago fell victim when they were unable to respond to a changing climate,” said Marcia McNutt, the director of the USGS, in a statement.
“This study illustrates that water availability was the climate-change Achilles Heel then for Egypt, as it may well be now, for a planet topping seven billion thirsty people.”
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The team of researchers set out to see if the pollen and charcoal remnants would match droughts that were found archaeological and historical records of the region.
Researchers believed that wetland pollen would likely decline in times of drought and the amount of charcoal would increase due to fires.
They were correct.
Pollen traces and increased charcoal matched earlier records of droughts in the area, said the French Tribune.
“Humans have a long history of having to deal with climate change,” said Christopher Bernhardt, a researcher with the US Geological Survey, in a statement.
“Along with other research, this study geologically reveals that the evolution of societies is sometimes tied to climate variability at all scales – whether decadal or millennial.”