Free Republic

Fish may have once swum across the Sahara, a finding that could shed light on how humanity made its way out of Africa, researchers said. The cradle of humanity lies south of the Sahara, which begs the question as to how our species made its way past it. The Sahara is the largest hot desert in the world, and would seem a major barrier for any humans striving to migrate off the continent. Scientists have often focused on the Nile Valley as the corridor by which humans left Africa. However, considerable research efforts have failed to uncover evidence for its...

The Sahara, the world's largest desert, was once fertile grassland. This fact has been common knowledge in the scientific community for some time, but scientists are still grappling with historic data to determine whether that transition took place abruptly or gradually. At the European Geosciences Union General Assembly held in Vienna, Austria earlier this year, researchers presented new evidence showing that the eastern region of the Sahara desert, particularly the area near Lake Yoa in Chad, dried up slowly and progressively since the mid-Holocene period.

Millions 'wasted' planting trees that reduce water By Charles Clover, Environment Editor (Filed: 29/07/2005) Millions of pounds in overseas aid are wasted every year planting trees in dry countries in the belief that they help attract rainfall and act as storage for water, scientists said yesterday. In fact, forests usually increase evaporation and help to reduce the amount of water available for human consumption or growing crops, according to a four-year study. Research on water catchments on three continents says it is "a myth" that trees always increase the availability of water. Even the cloud forests of tropical Costa Rica...