New Study Reassesses the Age of the Jordan Valley Ubaydiya Layer: Dating Back Approximately 2 Million Years, Comparable to Georgia’s Dmanisi Ruins. This Research May Mark a Critical Moment in Human Evolution, Indicating That Early Humans with Advanced Tool-Making Skills Expanded into New Environments Much Earlier Than Previously Believed.
Artist’s reconstruction of Homo erectus. Image credit: Yale University.
The Ubaydiya ruins are situated in Israel’s Jordan Valley, nestled between Menahemia village and Beit Zerah kibbutz.
Discovered in 1959, this site has yielded a distinctive Ature hatchet but only a few human remains.
“The Ubaydiya Formation has been a focus of research for years, offering early evidence of the Acheulean culture, recognized by its large, double-sided stone tools, often found alongside a diverse array of fauna, including species from Africa and Asia,” remarked Ali Matmon, a professor at the Hebrew University of Jerusalem.
“Yet, determining the precise age of this site has posed a considerable challenge over the decades.”
“Historically, researchers estimated Ubaydiya’s age to be between 1.2 and 1.6 million years, based on relative chronology.”
To ascertain the site’s true age, researchers employed three independent dating techniques: magnetic stratigraphy, uranium-lead (U-Pb) dating of mollusc shells, and cosmogenic isotope burial dating.
“Cosmogenic isotope burial dating measures rare isotopes generated when cosmic rays strike rocks on Earth’s surface,” explained the research team.
“Once buried, these isotopes decay at a known rate, effectively beginning a geological clock that indicates how long they have been underground.”
“We also analyzed remnants of Earth’s ancient magnetic field preserved in lake sediments at the site,” they added.
“As sediment settles, it locks in the orientation of the planet’s magnetic field at that time.”
“By correlating these magnetic signatures with known historical reversals in Earth’s magnetic field, we established that this formation emerged during the Matsuyama period, over 2 million years ago.”
“We also examined the fossils of melanopsis, utilizing U-Pb dating to determine the age of shells and freshwater snails within the sediment, which helped us establish the minimum age of the layer where the stone tools were discovered.”
“Overall, our findings indicate an age much earlier than previously anticipated.”
Double-sided stone tool excavated from the Ubaydiya site in Israel. Image credit: Omri Barzilai.
The team’s results indicate that the Ubaydiya site is at least 1.9 million years old, significantly older than prior estimates.
“This new chronology suggests that Ubaydiya is roughly contemporaneous with the renowned Dmanisi site in Georgia, implying that our ancestors migrated to different regions simultaneously,” the scientists noted.
“Additionally, this suggests that both simpler Oldowan and more advanced Acheulean stone tool-making techniques began their migration from Africa as various hominin groups explored new terrains.”
This groundbreaking study is published in the Quaternary Science Review.
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A. Matmon et al. 2026. The Complex History of Radiation Exposure Burials in the Dead Sea Rift Valley and the Recycling of Pleistocene Sediments Affecting the Age of the Acheulian Site Ubaydiya. Quaternary Science Review 378: 109871; doi: 10.1016/j.quascirev.2026.109871
Source: www.sci.news
