Guanches: Berber DNA and the chronicles of a people who couldn't sail

The Guanches were not sailors: someone took them to the Canary Islands

An archipelago more than a hundred kilometres off the African coast. A people of Neolithic culture who, when the Castilians arrived in the 15th century, knew nothing of sailing. And DNA that points, with no reasonable margin of doubt, to Berber North Africa. The equation does not add up on its own: someone had to bring the first Canary Islanders there, or they had to arrive with means that were later lost. The debate over how and why it peine remains open, and the answers on the table range from Roman deportation to a simple accidental shipwreck.

What ancient DNA says about the Guanche origin

The genetic evidence is the least open to dispute. An international team led by Stockholm University sequenced ancient DNA from the skulls of individuals who lived in Tenerife and Gran Canaria before the European conquest. The result: the Guanches were **more closely related to today's North Africans of Berber descent** than to any other population compared. Added to this is the examination of the alphabetic inscriptions and the place names of the seven islands, which points in the same direction.

The mitochondrial lineages detected indicate a clear origin in the **Maghreb** and, to a lesser extent, sub-Saharan Africa, probably from the ancient Roman province of Mauretania. The traceability of the genome also suggests that the Berbers arrived in considerable numbers: the remains of supplies, weapons and animal skeletons dated by carbon 14 indicate that they came **equipped to settle**, not just passing through.

The study also produced a figure that comes up again and again: today's inhabitants of Gran Canaria retain approximately between **16% and 31% Guanche genetic ancestry**. A wide range, but one that dismantles the idea that the native population died out without a trace.

Why is it believed the Guanches could not sail?

Because the chronicles of the first conquerors are explicit. The Norman pilots and the Castilian troops who arrived in the 15th century described the islanders as people without boats or nautical knowledge. There was a logic behind it: with 1st-century naval technology and **the northeast trade winds blowing all year round**, moving between islands was a trap. The currents between Tenerife and La Palma, for example, dragged ships southward with no possible return for a vessel of that era.

Hence a hypothesis that is gaining ground: the first settlers did not need ships because **they could not move from one island to another**. And if they could not return, there was no point in keeping the craft of shipbuilding alive. The technology would have been lost through sheer uselessness, not cultural involution.

The impossible return route and the Portuguese precedent

The nautical argument is stronger than it seems. Sailing ships heading to the Canary Islands **could not return by the same outbound route**: to get back they had to head into the Atlantic towards the northwest with the trade winds and then tack north until they caught the westerly winds above 35 degrees latitude. The Portuguese did not discover Madeira in 1418 by chance, but on one of those return voyages from the African coast.

If that was the case in the 15th century, with caravels, the question is what a low-freeboard Roman galley, with most of its space taken up by rowers, could have done. Galleys could not withstand ocean swells or long crossings. High-freeboard corbita-type ships were more suitable, but there is no record of Romans or Carthaginians having anything like a galleass. The unavoidable conclusion: **arriving was possible; returning, highly doubtful**.

Juba II, the Phoenicians and the purple-dye outpost on Lobos islet

The documented history of the settlement begins in Caesarea, present-day Cherchell in Algeria. From there, **Juba II**, a Romanized Berber monarch and scholar, financed the first expedition with documentary evidence to reach the islands, shortly after ascending the throne of Mauretania in 25 BC. Pliny the Elder recorded those accounts in his Natural History in AD 77, moving the archipelago from the realm of myth to that of real geography.

There had been earlier contacts. The geographer Statius Sebosus mentions the islands around 30 BC, and Agrippa's map, drawn before 12 BC, already includes them. And there is material evidence: the presence of **purple-dye producers on Lobos islet**, between Lanzarote and Fuerteventura, around 40 BC. Some argue that the Phoenicians, whose name is etymologically linked to the palm tree, had a thriving business in purple dye and a network of defensible island bases, and that stopping in the Canary Islands would fit with that activity.

Deportation, shipwreck or planned colonization

Here begins what remains unresolved. One school of thought holds that the first inhabitants were **forcibly relocated** trinc some rebellion in Roman Mauretania, and that the archipelago later became a kind of human farm from which slaving expeditions stocked up until the arrival of the Castilians. Another points to a migration forced by the **accelerated desiccation of the Sahara**, which would have pushed entire populations towards the coast and, from there, out to sea.

Some defend several successive migratory episodes rather than a single arrival, and others do not rule out pure accident: fishermen or traders swept along by currents and winds who ended up stranded on islands with no way back. Plutarch mentions some sailors who arrived from two Atlantic islands separated by a strait, identified as Lanzarote and Fuerteventura, which he called the Isles of the Blessed.

The unsettling detail: a civilization in retreat

One of the most striking facts in the Canary Islands' archaeological record is that the first settlers **knew agriculture and practised it for centuries**, but lost it at some point. The inhabitants of the 15th century lived by gathering and herding. They lost the seeds, or the knowledge, or both. A civilization can go backwards, and the Canary Islands offer a documented case.

They also practised **infanticide** when they calculated that the island could not support more people. Rudimentary population control in a closed subsistence economy. And there were no accessible metals on the islands: knowing about metallurgy would have been frustrating. The Canary Island pine, which grows over 40 metres tall, could be used to build boats, but without iron the project becomes complicated.

What remains unanswered

None of the pieces fits entirely. The DNA says Berber, the archaeology says a planned arrival with supplies, the nautical evidence says returning was almost impossible and the chronicles say they could not sail. Were they deported, or did they travel on their own? One arrival or several? Phoenicians, Romans or a chain of shipwrecks? The solid theory that ties up all the loose ends has yet to be written.