The route out of Africa. I’m Bob Hirshon and this is Science Update.
Anthropologists have long believed that modern humans first left Africa about 60,000 years ago. But a new study in the journal Science suggests that some migrated earlier. Scientists have discovered stone tools over 100,000 years old in what is now the United Arab Emirates. While today the route there is blocked by desert and ocean, the scientists say that back then, it was lush with forest and lakes.
In other news, 250 million years ago, before the time of the dinosaurs, most life on earth was wiped out. In the journal Science, researchers claim it was caused by volcanoes that set massive beds of coal on fire. The greenhouse gases from the burning coal warmed the atmosphere and led to the widespread extinctions. The researchers base their findings on seams of coal ash they found in rocks dating from the period. I’m Bob Hirshon for AAAS, the Science Society.