WASHINGTON (AP) — Huw Groucutt passes rolling sand dunes as far as his eye can see when traveling to archaeological sites in the northern Arabian Peninsula. But the same desert regions were once intermittently lush and green, attracting early humans and large animals such as hippopotamuses migrating out of Africa to linger at ancient lakes, new evidence suggests. “We noticed color patterns made by ancient lakes — sand dunes are kind of orange-colored, while ancient lakes are tinted white or gray,” said Groucutt, who is also based at the Max Planck Institute. Extensive excavations over a decade revealed stone tools from multiple periods of prehistoric settlement by early human groups, the oldest 400,000 years ago. During these windows of hospitable climate, early humans and animals moved from northeast Africa into the Arabian Peninsula, the researchers say.
