With his multidisciplinary calling, Wegener had started out as an astronomer, being correct when he stated that craters on the Moon are the work of meteorites and not of volcanoes; later, he combined meteorological studies in Greenland with his geological theories, and did not have a steady job until after the age of 40, when an Austrian University created a post for him. He was a difficult scientist to pigeonhole. And for geologists he was an outsider who dared to question the foundations of their science, so most of them rejected his ideas with the backing of figures like Einstein, who wrote the prologue to a book that ridiculed Wegener.
It is also true that he made some blunders, calculating that Greenland was approaching North America at a rate of 1. That was like saying that a plough can move on its own and leave no furrows.
Tests were done, but with the most reliable instruments of the time no movement of the continents was detected. The edition of the Encyclopedia Britannica still did not believe Wegener, but that year many geologists began siding with him, in view of new evidence. This new theory— plate tectonics —also explained that earthquakes and tsunamis occur when two plates rub against one another, and that when they collide head-on, large mountain ranges are formed.
In addition, thanks to geolocation satellites, we are now able to detect that Europe and North America are moving apart, although at the same speed that a fingernail grows: two metres in a lifetime. Today we have all learned at school—or even before, in cartoons—the theory of continental drift. But Wegener died in , long before his success was recognised.
During an expedition in Greenland, he left the camp for supplies and was found frozen months later. He was buried there and is still there, although he is now about two metres further away from his birthplace in Berlin. Click Enter. Login Profile. Es En. But no one had made much of it, and Wegener was hardly the logical choice to show what they had been missing. He was a lecturer at Marburg University, not merely untenured but unsalaried, and his specialties were meteorology and astronomy, not geology.
But Wegener was not timid about disciplinary boundaries, or much else. He cut out maps of the continents, stretching them to show how they might have looked before the landscape crumpled up into mountain ridges.
Finally, he pointed out how layered geological formations often dropped off on one side of an ocean and picked up again on the other, as if someone had torn a newspaper page in two and yet you could read across the tear. Wegener published his idea in an article that April to no great notice. Later, recovering from wounds he suffered while fighting for Germany during World War I, he developed his idea in a book, The Origin of Continents and Oceans , published in German in When it was published in English, in , the intellectual fireworks exploded.
But it was the Americans who came down hardest against continental drift. The most poignant attack came from a father-son duo. Chamberlin had launched his career with an iconoclastic attack on establishment thinking.
Find a map of the continents and cut each one out. Better yet, use a map where the edges of the continents show the continental shelf. The easiest link is between the eastern Americas and western Africa and Europe, but the rest can fit together too. Alfred Wegener proposed that the continents were once united into a single supercontinent named Pangaea, meaning all earth in ancient Greek.
He suggested that Pangaea broke up long ago and that the continents then moved to their current positions. He called his hypothesis continental drift. Besides the way the continents fit together, Wegener and his supporters collected a great deal of evidence for the continental drift hypothesis.
For one, identical rocks of the same type and age are found on both sides of the Atlantic Ocean. Wegener said the rocks had formed side-by-side and that the land had since moved apart. Mountain ranges with the same rock types, structures, and ages are now on opposite sides of the Atlantic Ocean.
Wegener concluded that they formed as a single mountain range that was separated as the continents drifted. Ancient fossils of the same species of extinct plants and animals are found in rocks of the same age but are on continents that are now widely separated.
Wegener proposed that the organisms had lived side by side, but that the lands had moved apart after they were dead and fossilized. He suggested that the organisms would not have been able to travel across the oceans. For example, the fossils of the seed fern Glossopteris were too heavy to be carried so far by wind. The reptile Mesosaurus could only swim in fresh water.
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