a New Researchpublished in the journal Geoscience Reviewhelps resolve one of the longest-running debates in paleoanthropology: when did early humans arrive in Europe?
“chronology Homo “Migration out of Africa has expanded substantially over the past 40 years,” said paleoanthropologist Luis Hibbert of the University of Barcelona and his colleagues.
“In 1982, Homo The Asian volcano has been paleomagnetically dated to 900,000 years ago in Java and 700,000 years ago in Italy, Europe.
“Forty years later, the early Homo Outside of Africa, the South Caucasus dates back 1.8 million years, China 1.7-2.1 million years ago, and Java 1.5-1.3 million years ago.
“In Europe, several sites are found to have layers of paleomagnetic polarity reversal several metres deep, indicating that they are more than 770,000 years old.”
In the study, the authors used magnetostratigraphic dating, a method that uses the state of the Earth's magnetic field at the time the sediments were deposited, to date five paleontological localities in the Orce region of Spain.
“The technique is a relative dating method based on the study of the planet's magnetic pole reversals due to the dynamics of the Earth's interior,” they explained.
“These changes have no particular periodicity, but they are recorded in minerals and it is possible to establish periods from various magnetic events.”
“What's unique about these sites is that they are layered and sit within a very long sedimentary layer, over 80 metres long,” Dr Zibert said.
“Typically these sites are found in caves or within very short geological sequences, so it's not possible to develop long paleomagnetic sequences where you can find the different magnetic reversals.”
Global distribution of humans before 1 million years ago (orange) with major dated sites showing potential dispersal routes. The diagram shows Oldowan sites over 2 million years ago in Africa and over 1 million years ago in Eurasia (black dots). White dots indicate the earliest Acheulean sites in Africa (over 1.5 million years ago) and Eurasia (1 million to 800,000 years ago). The oldest Oldowan and Acheulean tools have been found in East Africa, over 2.5 million years ago and over 1.7 million years ago, respectively. In Asia, the oldest Oldowan and Acheulean tools have been found in the Caucasus (7) at 1.8 million years ago and in the Levantine Corridor (9) at 1.2 million years ago, respectively. In Europe, the oldest Oldowan and associated humans have been found in Spain (1, 2) and are debated to be between 1.6 and 900,000 years ago. Images/Photos Courtesy of: Gibert others., doi: 10.1016/j.earscirev.2024.104855.
The oldest remains at the Orce site, which have no evidence of human activity, date to 1.6 million and 1.35 million years ago, according to the study.
The top three sites containing evidence of early humans are dated 1.32 million years ago (Venta Misena), 1.28 million years ago (Barranco Leon 5), and 1.23 million years ago (Fuente Nueva 3).
These chronologies suggest that the Strait of Gibraltar acted as a filter bridge for African species such as hominins. Theropithecus Oswaldand the early Pleistocene hippopotamus.
“This new dating adds to other evidence and supports European colonization through the Strait of Gibraltar rather than the alternative route back to the Mediterranean via Asia,” the scientists said.
“We also support the hypothesis that they arrived from Gibraltar, as no older evidence has been found elsewhere along the alternative route.”
“Our results show a dating gap between the earliest occupation of Asia, 1.8 million years ago, and the earliest occupation of Europe, 1.3 million years ago. This means that African humans arrived in southwestern Europe more than 500,000 years after they first left Africa around 2 million years ago.”
“These differences in human expansion can be explained by the fact that Europe is isolated from Asia and Africa by difficult-to-surmount biogeographical barriers both to the east (the Bosphorus, the Dardanelles and the Sea of ​​Marmara) and to the west (the Strait of Gibraltar),” Dr. Zibert said.
“When humans arrived in Europe, they had the technology necessary to cross the maritime barrier, just as happened a million years ago on the Indonesian island of Flores.”
“In this sense, the Gibraltar route currently requires crossing a sea channel of up to 14 kilometres, although in the past this distance could have been shorter at certain times due to the tectonically active nature of the region and sea-level changes favourable for migration.”
“We found that African animals were migrating through Gibraltar both 6.2 million years ago and 5.5 million years ago, when the Strait of Gibraltar was very narrow.”
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Lewis Guibert othersMagnetic strata dating of Europe's oldest human remains. Geoscience ReviewPublished online July 2, 2024; doi: 10.1016/j.earscirev.2024.104855
Source: www.sci.news
