Study: Humans May Have Played Pivotal Role in Desertification of Sahara
It seems impossible to imagine, but where the Sahara is dominated today by a landscape of sand dunes, just a few thousand years ago, it was a vast grassland dotted with lakes.
An archaeologist has now suggested that we humans played a pivotal role in bringing on the rapid changes in ecology that caused a drop in rainfall, which could provide us with insights into how we'll cope with large scale climate change in the future.
Deep beneath the Sahara's sands are signs of old rivers and traces of plants and animals, preserving reminders of the region's greener past.
The roughly 10,000-year stretch of what's called the African Humid Period is largely considered to have been caused by an episode of monsoons that washed over the continent - just one of a cycle of such wet periods dating back 9 million years that current hypotheses claim ended with changes in Earth's orbit.
While the current thinking blames a 20,000 year 'wobble' in our planet's orbital axis for ending the last big wet, David Wright from Seoul National University isn't convinced.
Dave Price