Alfred Lothar Wegener

Alfred Lothar Wegener (1880 - 1930) was a German meteorologist proponent of plate tectonic theory and continental drift.

In the fall of 1911 in Marburg, Wegener was researching in the university library when he came across a scientific article that recorded fossils of identical animals and plants found on opposite sides of the Atlantic. Intrigued by this fact, Wegener successfully began researching other cases of similar organisms separated by oceans. The orthodox scientific community of the time attempted to explain these cases by claiming that earthen bridges, now submerged, once linked the continents. Wegener also noted that the coasts of Africa and South America fit together. Could the similarities between organisms then be due not to the existence of terrestrial bridges, but to the fact that the continents were once linked?

Such a theory, to be accepted, would require a great deal of evidence to support it. Wegener then discovered that large geological structures on different continents seemed to be linked. For example, the Appalachians in North America were linked to the Scottish Highlands and the rocky strata in South Africa were identical to those found in Santa Catarina in Brazil.

The meteorologist also found that fossils often found in certain locations indicated a very different climate from today's climate. For example, fossils of tropical plants were found on the Arctic Spitsbergen Island.

All these facts supported Alfred Wegener's theory of continental drift. In 1915 the first edition of The Origin of Continents and Oceans , where Wegener explained his theory, was published from other editions in 1920, 1922 and 1929. Wegener claimed that about 300 million years ago the continents formed a single mass, Pangeia (from the Greek "all the earth"). Pangeia has fragmented and its fragments have been "drifting" ever since. Wegener was not the first to suggest that the continents were in connected times, but he was the first to present extensive evidence from various fields of study.

Reactions to Wegener's theory were almost always hostile and often harsh. Part of the problem was that Wegener had no convincing theory that explained the mechanism that made the continents move. He thought that the continents moved in the earth's crust as icebergs move through the ice sheets and that the centrifugal and tidal forces were responsible for the movement of the continents. Another problem was the flaws in Wegener's data that led him to make wrong predictions. He suggested that North America and Europe drifted apart at a rate of 250 cm per year (about a hundred times faster than in reality). However, there were scientists who supported Wegener, such as South African geologist Alexander Du Toit. After his death his theories had some supporters but most geologists continued to defend the theory of static continents and land bridges.