Tag Archives: Azores

The Vikings (and their mice) were the first to reach these idyllic Portuguese islands

If you were living in the cold and rugged landscapes of medieval Scandinavia, exploring other places probably sounded like a good idea. Especially if it’s a place like the Azores — an archipelago of nine inviting islands in the middle Atlantic, some 1400 km (860 m) from Portugal’s coastline.

According to a new study, Viking explorers did just that: they reached the Azores centuries before Portuguese explorers. When the Portuguese came, they didn’t find any traces of the Vikings, but a new study detected “unambiguous” evidence that the Vikings were indeed the first on the islands.

Image credits: Martin Munk.

In 1427, a Portuguese navigator set foot on an uninhabited, idyllic island. With its lush cliffs, beautiful beaches, and deep blue waters, the island must have been a sight to behold. We’re not really sure what the explorer’s name was — he is only known from a reference on a chart drawn by a Catalan cartographer in 1439, and the map was marred by an inkwell accident in 1869 that partially smudged the explorer’s name.

Historians suspect that his name was either Diogo de Sunis or Diogo de Silves — but whatever it was, he must have thought he discovered a new part of a previously unknown land. Later Portuguese explorers confirmed his finding and revealed it to be a part of the Azores archipelago, nine volcanic islands.

Nowadays, the Azores islands are as dramatic as ever, but they’ve been settled by the Portuguese for centuries. However, some researchers suspected that this may not be the whole story. Particularly, that someone (Vikings) was on the island before the 15th century.

But since there was no archaeological evidence (that was found yet, at least) to support that idea, they had to look for evidence in other places.

In 2015, a study found some evidence in the unlikeliest of places: mice. The study noted intriguing genetic similarities between mice in the Azores and in Northern Europe. But as tantalizing as this evidence was, it was insufficient to draw any clear conclusions. Now, the needed evidence may have finally been discovered.

An old map of the Azores islands.

Around a decade ago, Pedro Raposeiro, an ecologist at the University of the Azores, Ponta Delgada wanted to explore the Azores’ climate by analyzing sediment cores from lakebeds across the archipelago. This is a common approach used by many climate scientists, and the layers of sediment from the cores can be dated pretty accurately.

But in addition to climate information, researchers also found signs of human disturbance: pollen from non-native crops that explorers would have brought along and spores from fungi that grow on livestock dung. This was not surprising — but what was surprising was that these traces extended all the way back to 700 years before the Portuguese settled on the Azores.

In one particular layer, that was dated to AD700-850, researchers found clear signs of human activity: an increase in charcoal particles, a dip in the pollen of native trees, and a compound (5-beta-stigmastanol) that is found in the feces of animals such as cows and sheep. This suggests that some of the island’s trees were being cut down and burned, presumably to make way for pastures.

Similar signs were found in a layer dated to 100 years later, as well as in layers dated to 1150 and 1300 respectively.

“The occupation of these islands began between 700 and 850 CE, 700 years earlier than suggested by documentary sources. These early occupations caused widespread ecological and landscape disturbance and raise doubts about the islands’ presumed pristine nature during Portuguese arrival,” the researchers write in the study.

The Azores.

The team adds that the Norse were likely the ones who first set foot on the Azores. They were among the few who had the technology to reach the islands (or perhaps the only ones), and by the 8th century, various areas in Europe noted that they were reached (and attacked) by Norse seafarers. While there’s no smoking gun pointing to the Vikings, they are the most likely culprits.

“These results are consistent with recent archaeological and genetic data suggesting that the Norse were most likely the earliest settlers on the islands.”

So what happened to them? When the Portuguese arrived in the Azores, they described the islands as “pristine” and said they found no trace of anyone, so the previous settlers had already left for some time, for reasons that are not entirely clear. That’s a story for another time.

The study was published in PNAS.

Researchers find rare hydrothermal vent off the coast of Portuguese islands

Researchers have discovered a new hydrothermal vent near the Gigante Seamount in the Azores — Portuguese islands in the Mid-Atlantic region.

Map of the Gigante seamount with the Mid Atlantic Ridge separating the North American and Eurasian plates. Image from the Hydrographic Institute of the Portuguese Navy.

Surveying the pristine seas around the Azores Islands, researchers from the University of the Azores (IMAR–UAz) were thrilled to discover a previously unknown hydrothermal vent. Telmo Morato, ATLAS principal investigator at IMAR–UAz, who is leading the expedition dives, summed up the finding in just four words: “this is just fantastic!”

The reason why Morato is so excited is not only because he found a new hydrothermal vent — one of the rares and most unique ecosystems on Earth — but also because this one is much more easily accessible than other such systems, which makes it much easier to study. Hydrothermal fields are poorly understood so far, largely because they are so remote and difficult to study.

[panel style=”panel-default” title=”Hydrothermal vents” footer=””]Hydrothermal vents are essentially cracks in the planet’s surface from which geothermally heated water rises. They’re commonly found in volcanically active areas, where tectonic plates are moving apart at spreading centers, ocean basins, and hotspots.

Chimney of the new vent field where hydrothermal activity is visible. Image from ROV “LUSO”, Portuguese Task Force for the Extension of the Continental Shelf.

Because this unusual setting provides heat and useful nutrients, the areas around submarine hydrothermal vents are biologically more productive, often hosting complex communities fueled by the chemicals dissolved in the vent fluids. Chemosynthetic bacteria and archaea form the basis of the food chain, which supports bizarre creatures such as giant tube worms, clams, limpets and shrimp.

Researchers are also very interested in hydrothermal vents since such environments are thought to exist on Jupiter’s moon Europa and Saturn’s moon Enceladus, where they may very well be capable of supporting life.[/panel]

The discovery was made using the Portuguese ROV “Luso”, which is capable of diving to a depth of a staggering 6,000 m. The vent itself lies at a depth of “only” 570 m, some 100 km away from the Faial Island, sometimes considered the westernmost point of Europe, even though tectonically it lies on the North American Plate.

Highlighted here: Faial Island, a Portuguese island with a population of approximately 15,000 people. The vent lies just 100 km from the island. Image via Google.

The researchers have already found evidence that bacteria are growing in great numbers around these vents and are likely to support other, more complex life forms. Although the environment is dark and frigid, these chemosynthetic bacteria don’t need sunlight to survive and can form the base of surprisingly rich food chains. With heat also coming from the vent, all the conditions are met for supporting this type of ecosystem.

This unexpected discovery is a huge step forward for deep-sea exploration and the better understanding of these untouched ecosystems. Currently, only 3% of the ocean is protected, and the team is gathering more data to see if the newly-discovered vent fits the required criteria to be considered endangered.

Professor Murray Roberts, ATLAS Project coordinator at the University of Edinburgh, said:

‘This just shows how little we know about the deep sea, the largest ecosystem on our planet. Hydrothermal vents not only form oases of life in the deep ocean, but research over the last 20 years has shown the minerals they release also have important consequences for life throughout the ocean. As plans to mine deep sea minerals are developed around the world it’s absolutely essential we understand these relationships to protect the oceans and the support functions they provide to all life on Earth.’