Arabia was a green corridor 400,000 years ago that channeled the first human migrations

Every year thousands of people move fleeing the effects of climate change, but climate variations have not always hurt humans. 400,000 years ago, repeated episodes of increased precipitation transformed Arabia into a lush region that facilitated the first migrations from Africa to Eurasia.

These migrations have taken place on at least five occasions: 400,000 years ago, 300,000 years ago, 200,000 years ago, 100,000 years ago and, the last, about 55,000 years ago, and in each of them humans have left a trace of their material culture and their stone tools.

Evidence of this has been found in the Nefud Desert (Saudi Arabia), in archaeological sites that, in the Pleistocene, were home to large lakes caused by episodes of intense rains.

The results, detailed today in an article in the journal Nature, confirm that Arabia, located between Africa and Asia, was a crossroads for many human populations and a crucial migratory route to the Mediterranean Levant (now the Middle East) and to Eurasia.

Although this region is essential for reconstructing the movements and migrations of human evolution between continents, its aridity and the scarcity of fossil records have always made paleontological study difficult. Until today.

The work, led by the Max Planck Institute for the Science of Human History in Jena (Germany) and the Heritage Commission of the Saudi Ministry of Culture, documents the human presence in Arabia for 400,000 years, the oldest found to date.

For Huw Groucutt, lead author of the study and director of the Max Planck Society Research Group, this work represents a “great advance” for paleontology because it confirms the strategic importance of the region and because “it shows that we still know very little about human evolution in vast regions of the world and that many surprises still await us ”.

The researchers searched two places: the Khall Amayshan 4 (KAM 4) deposit, nestled in a hollow between large dunes, where they found evidence of six phases of lake formation; in five of them there were stone tools made by man between 400,000 and 55,000 years ago and belonging to different Paleolithic cultures.

The other excavation site was the oasis of Jubbah, 150 km to the east, where stone tools between 200,000 and 75,000 years old have also been recovered.

Between the two sites, researchers discovered two types of Acheulean technology – associated with earlier hominids such as Homo erectus – and three with different forms of Middle Paleolithic technology, including axes and blades.

Scientists also dated reservoir sediments using luminescence techniques., who record the time since the last time they were exposed to light, and found that each occupancy coincided with a season of increased precipitation.

They also confirmed that while the climate of Arabia was arid, events of increased rainfall would occur periodically, which worked the miracle and turned deserts into green grasslands with lakes, wetlands and rivers. which crossed most of Arabia, attracting all kinds of animals and also humans.

“It’s extraordinary; every time there was humidity, people would come”, says the project director, Michael Petraglia, of the Max Planck Institute, for whom “This work places Arabia on the world map of human prehistory.”

The findings of Khall Amayshan 4 and Jubbah reveal short periods of occupation with distinct material cultures, suggesting that populations came to the region from several directions and places of origin and indicating the existence of heavily subdivided populations in East Asia. Southwest at this time.

Besides, the differences in material culture are so great that they indicate that this region was occupied by different species of hominids at the same time, which means that Arabia could also be a place of connection for different groups of hominids from Africa and Eurasia, the authors conclude. .

Animal fossils, on the other hand, also exhibit a similar pattern: although the fossils have a marked African character (hippos), some species come from the north and others represent ancient inhabitants of Arabia (horses and camels). ).

(with information from the EFE)

KEEP READING: