One hundred years ago, a German explorer and scientist published a work that would revolutionise our understanding of our planet. In The Origin of Continents and Oceans, Alfred Wegener proposed the radical idea that Earth’s continents had, hundreds of millions of years before, formed a vast single land mass that had subsequently broken apart, with those broken pieces eventually drifting to their current locations. Our world’s mountains, forests and civilisations rest on a bedrock that is not immutable but shifts, albeit very slowly, Wegener argued.

David Attenborough recalls asking a lecturer in the 40s about continental drift. 'It was moonshine, I was informed.'

Other scientists had already mused on the possibility that the continents drift over geological time. But Wegener – who first outlined his theory at a scientific meeting in 1912 – took it seriously, collecting a mass of supporting evidence to support the book which, three years later, outlined the idea of continental drift to the public for the first time.

He noted the close resemblance of fossils of vertebrate animals and plants on opposite sides of oceans, and of the rock sequences that aligned the coasts of continents – for example western Africa and eastern South America. These similarities exist because these sites had once been contiguous, he claimed.

“At the time, scientists believed continents had been linked by land bridges over which species had spread but which had sunk and disappeared,” says palaeontologist Richard Cifelli, of Oklahoma University. “Wegener dismissed the idea of land bridges and argued instead that the continents had once been united.”

Wegener during his final expedition, 1930. Photograph: ullstein bild via Getty Images

The trouble was that he could provide no mechanism to explain how continents drifted. As a result, his work was derided and ignored for decades with hostility that endured for half a century. David Attenborough recalls asking a geology lecturer at Cambridge in the late 40s why he was not giving lectures about continental drift. “The idea was moonshine, I was informed.”

Proof that Wegener was correct all along was not provided until the 1950s and 60s with the discovery of sea-floor spreading, which causes oceans like the Atlantic to expand. We now know that Earth’s outer shell is divided into several plates that glide over the mantle, the rocky inner layer that lies above our planet’s molten core. Some plates slowly move apart, and hot magma wells up through the gaps.

For example, the upwelling from the diverging Eurasian and North American tectonic plates is forcing Europe and America apart, and has created a mid-Atlantic ridge with Iceland near its apex. However, when plates push together, one is forced down – or subducted – below the other, creating regions that are often associated with intense vulcanism.

As for Wegener the scientist, his biographer, Mott Greene, describes the man as “friendly, informal, somewhat introverted and deeply committed to his work”. In the end, that commitment cost him his life. In 1930, he and a colleague, Rasmus Villumsen, were exploring in Greenland when Wegener dropped dead, probably of a heart attack. Villumsen buried his body and marked the grave with skis. (Villumsen then walked on to try reaching a nearby camp but was never seen again.)

Watch the trailer for Science, Exploration, and the Theory of Continental Drift

A later expedition, led by Wegener’s brother Kurt, built a pyramid-shaped mausoleum round Alfred’s body, which over the years has become buried under layers of ice and snow.Intriguingly, his body, entombed in ice, has also sailed westwards at a rate of about two centimetres per year as it has been carried on the back of the North American tectonic plate.

As Cifelli, writing with Marco Romano, of Sapienza University of Rome, states in Nature this month: “Wegener would have been glad to know that his body will have travelled some 20 kilometres in a million years’ time – in accordance with his visionary theory.”