Fish Swam the Sahara, Bolstering Out of Africa Theory

Live Science (Charles Q. Choi)

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 consistent use by people leaving the continent, and precisely how watery it has been over time is controversial.

Now it turns out the Sahara might not have been quite as impassable as once thought — not only for humanity, but for fish as well.