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Lapa do Picareiro Cave Findings Rewrite History of Human Migration

Lapa do Picareiro Cave Findings Rewrite History of Human Migration

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Archaeological excavations at the Lapa do Picareiro cave in Portugal have revealed Palaeolithic stone tools that are rewriting the history of the settlement of Europe by modern humans. The find proves that Homo sapiens arrived in the west of Iberia some 5000 years earlier than once thought. The dating of the site’s artifacts, from approximately 40,000 years ago, indicates that modern humans co-existed with Neanderthals ( Homo neanderthalensis ) for a considerable period. This has implications for our understanding of the reasons for the extinction of this species of archaic humans.

The exciting discoveries were made in a cave named Lapa do Picareiro, which is in a karst mountain range in central Portugal and not far from the Atlantic coast. Archaeologists have been excavating the Lapa do Picareiro cave for almost a quarter of a century and have unearthed many important finds. A team of American, Portuguese, and Czech researchers, during a recent dig, unearthed some Aurignacian stone tools. This kind of blade technology was only made by anatomically modern humans. The blades date from the Palaeolithic era based on the carbon dating of organic evidence at the site.

Aerial view of Lapa do Picareiro in central Portugal, where the Aurignacian artifacts were unearthed. (Jonathan Haws / University of Louisville)

Aerial view of Lapa do Picareiro in central Portugal, where the Aurignacian artifacts were unearthed. (Jonathan Haws / University of Louisville )

Early Humans Reached Europe Earlier Than Previously Thought

Archaeologists believe that these Aurignacian artifacts indicate that early human inhabitation of Lapa do Picareiro is “5,000 years older than any Upper Palaeolithic site in westernmost Eurasia,” explain the researchers in PNAS. This challenges existing ideas about the migration of modern humans into Europe. Aurignacian artifacts provide a trail of evidence for the migration of anatomically modern humans into Europe and these artifacts have been discovered at sites ranging from Russia to France. According to PNAS, the discovery of the stone tools supports the theory of “a very rapid, unimpeded dispersal of modern humans across western Eurasia.”

It now appears that Homo sapiens spread across Europe only a few thousand years after they first appeared in south-east Europe, possibly prompted by climate change . Experts now believe that early humans made their way into Europe by an east-west route from the Eurasian Steppe, following river valleys. The discovery in the cave is very important for our understanding of the migration process. John Yellen, of the National Science Foundation which backed the project, told Uofl News that “the spread of anatomically modern humans across Europe many thousands of years ago is central to our understanding of where we came from as a now-global species.”

Aurignacian tools discovered in Lapa do Picareiro in central Portugal. (Jonathan Haws / University of Louisville)

Aurignacian tools discovered in Lapa do Picareiro in central Portugal. (Jonathan Haws / University of Louisville )

Portuguese Cave Findings Challenge History of Neanderthals

These tools also seem to confirm that Iberia was occupied much earlier than previously thought, based on recent discoveries made at the Bajondillo cave in southern Spain. The researchers wrote in PNAS that the “Iberian Peninsula holds a peculiar place in the problem of modern human dispersal.” Previously it was believed that early humans mainly lived north of the Ebro Valley. It was also assumed, based on finds from Gibraltar, that the Neanderthals persisted south of the Iberian Peninsula until about 37,000 years ago, possibly the last of their species in Europe.

However, the recent finds in the Portuguese cave have seriously challenged this view. Lapa do Picareiro was inhabited by Neanderthals before the arrival of modern humans. Based on a cave site nearby, and the dating, it appears that the Neanderthals continued to live in the region and co-existed with modern humans. This means that the extinct species of humans were the neighbours of our ancestors in Portugal during the Upper Palaeolithic.

View from the entrance of the Lapa do Picareiro cave during archaeological excavations. (Jonathan Haws / University of Louisville)

View from the entrance of the Lapa do Picareiro cave during archaeological excavations. (Jonathan Haws / University of Louisville )

Did Neanderthals and Modern Humans Interbreed?

The Daily Mail quotes the researchers as saying that the tools found have “‘important ramifications’ for understanding the possibility of interactions between modern humans and Neanderthals in the region.” The unearthing of these tools shows that it is highly unlikely that our ancestors appeared in an area that was depopulated and devoid of Neanderthals. The two species of humans probably interacted. “If the two groups overlapped for some time in the highlands of Atlantic Portugal, they may have maintained contacts between each other,” explains Nuno Bicho in Eureka Alert . Based on the genetic inheritance of many modern people, these contacts may have included breeding.

Lukas Friedl of the University of Bohemia is quoted in the Daily Mail as stating that “the question whether the last surviving Neanderthals in Europe [were] replaced or assimilated by incoming modern humans is a long-standing, unsolved issue.” However, the Neanderthals were not assimilated by our ancestors and remained separate. This is evident in the fact that the Neanderthals did not adopt the Aurignacian stone technology. Eureka Alert reports that “despite the overlap in dates, there does not appear to be any evidence for direct contact between Neanderthals and modern humans” at the site.

Survival of the Fittest

These findings may support the view that modern humans outcompeted the Neanderthals. Our ancestors’ technologies and social organization may have been superior, which could have allowed them to flourish at the expense of other species of archaic humans. Evidence has shown that the population of Neanderthals was very small and lacked genetic diversity. They were therefore possibly vulnerable to any dramatic changes or to the increased competition from modern humans. However, the finds do not definitively discount the possibility that our ancestors could have brought diseases with them, which then went on to exterminate the Neanderthals.

These new findings would tend to support the theory that modern humans simply replaced Neanderthals. The “results support the notion of a mosaic process of modern human dispersal and replacement of indigenous Neanderthal populations,” the researchers wrote in PNAS. Work is continuing at the site and more artifacts that could shed light on the early human occupation of Iberia, human migration and the demise of the Neanderthals may come to light.

Top image: Photograph showing the excavation site at the Lapa do Picareiro cave in central Portugal. The excavation of the early modern human can be seen in the foreground and the Neanderthal layers in the background. Source: Jonathan Haws / University of Louisville

By Ed Whelan

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