Arabia’s Hidden Green Past May Have Facilitated Early Human Migration, Shows Study

The modern arid desert region called Arabia located between Africa and Saudi Arabia was once lush and green with rivers and lakes over a period of 8 million years, enabling movement and occupation of both animals and hominins, according to a study "Recurrent humid phases in Arabia over the past 8 million years" published in the journal Nature.

“I visited Saudi Arabia as part of a Fulbright award. I was curious why no one was integrating Arabia into the Out of Africa story and wanted to assess the situation firsthand myself. At the time, I was working in India and I had hypothesised that movements out of Africa would have been across the Arabia-India zone,” Michael Petraglia, director of the Australian Research Centre for Human Evolution, leader of the ‘Green Arabia’ project, and a coauthor of the study, told The Hindu.

According to The Hindu, for decades, researchers believed that the Arabian Peninsula was always a barren land with a foreboding environment and where humans had only settled a few thousand years ago, especially once they had managed to domesticate animals like camels and goats. This belief kept Arabia excluded from the theories of ‘Out of Africa’ — a model that suggests modern humans originated in Africa and then migrated to the rest of the world.

The ‘Green Arabia’ hypothesis challenges this belief and indicates that this now-arid land had the occasional humid or rainy phases that transformed it into a wet and verdant terrain, with hints of rivers and lakes that were capable of sustaining diverse plant and animal life.

Arabia's Hidden Green Past

Speleothem and archaeological research indicate that Arabia periodically transformed into lush grasslands studded with lakes and rivers, forming crucial human migration corridors over the past 400,000 years. These “Green Arabia” phases allowed multiple waves of hominin and modern-human movement between Africa and Eurasia, forming key migration routes for humans and animals such as hippos and underscoring Arabia’s connection with human evolutionary history, according to reports published by the Max Planck Institute for the Science of Human History and Proceedings of the National Academy of Sciences.

“Arabia has not been part of the story of early human migration because so little work was done there before,” co-author Michael Petraglia, a paleolithic archaeologist at the Max Planck Institute for the Science of Human History in Jena, Germany told Washington Post. The research team comprised of scientists from Germany, Saudi Arabia, Australia, the United Kingdom and elsewhere.