Hand axes, hippo bones, and a stack of ancient lake beds show that arid Arabia experienced intervals of humid weather, spurring pulses of human migration over the past 400,000 years.
Recent research combining analysis of carbon dating, sediment accumulation rates, and pollen records from 632 lake beds worldwide finds deforestation tied to increased soil erosion.
Researchers have found cyanobacteria colonies as big as softballs thriving unexpectedly on shallow Greenland lake bottoms, exuding liver-damaging microcystin. Locals dubbed them "sea tomatoes."
Greener, Wetter Arabia Was a Crossroads of Early Human Migration
