Editing Continental drift (section)

=== Wegener and his predecessors ===
[[File:Alfred Wegener 1910.jpg|left|thumb|upright=.75|Alfred Wegener]]

Apart from the earlier speculations mentioned above, the idea that the American continents had once formed a single landmass with Eurasia and Africa was postulated by several scientists before [[Alfred Wegener]]'s 1912 paper.<ref name="Wegener-1912" /> Although Wegener's theory was formed independently and was more complete than those of his predecessors, Wegener later credited a number of past authors with similar ideas:<ref name="Wegener-1966" /><ref name="Wegener-1929" /> Franklin Coxworthy (between 1848 and 1890),<ref name="Coxworthy-1924" /> [[Roberto Mantovani]] (between 1889 and 1909), [[William Henry Pickering]] (1907)<ref name="Pickering-1907" /> and [[Frank Bursley Taylor]] (1908).<ref name="Taylor-1910" />

The similarity of southern continent geological formations had led [[Roberto Mantovani]] to conjecture in 1889 and 1909 that all the continents had once been joined into a [[supercontinent]]; Wegener noted the similarity of Mantovani's and his own maps of the former positions of the southern continents. In Mantovani's conjecture, this continent broke due to [[Volcanism|volcanic]] activity caused by [[thermal expansion]], and the new continents drifted away from each other because of further expansion of the rip-zones, where the oceans now lie. This led Mantovani to propose a now-discredited [[Expanding Earth theory]].<ref name="Mantovani-1889" /><ref name="Mantovani-1909" /><ref name="Scalera-2003" />

Continental drift without expansion was proposed by [[Frank Bursley Taylor]],<ref name="Lane-1944" /> who suggested in 1908 (published in 1910) that the continents were moved into their present positions by a process of "continental creep",<ref name="Taylor-1910a" /><ref name="Frankel-2012" /> later proposing a mechanism of increased tidal forces during the [[Cretaceous]] dragging the crust towards the equator. He was the first to realize that one of the effects of continental motion would be the formation of mountains, attributing the formation of the Himalayas to the collision between the [[Indian subcontinent]] with Asia.<ref name="Powell-2015" /> Wegener said that of all those theories, Taylor's had the most similarities to his own. For a time in the mid-20th century, the theory of continental drift was referred to as the "Taylor-Wegener hypothesis".<ref name="Lane-1944" /><ref name="Powell-2015" /><ref name="Hansen" /><ref name="Wood-2016" />

Alfred Wegener first presented his hypothesis to the German Geological Society on 6 January 1912.<ref name="Wegener-1912" /> He proposed that the continents had once formed a single landmass, called [[Pangaea]], before breaking apart and drifting to their present locations.<ref name="Wegenerproofs">{{cite web |url = http://www.bbm.me.uk/portsdown/PH_061_History_b.htm |title = Wegener and his proofs |archive-url=https://web.archive.org/web/20060505053619/http://www.bbm.me.uk/portsdown/PH_061_History_b.htm |archive-date=5 May 2006 |url-status=dead}}</ref>

Wegener was the first to use the phrase "continental drift" (1912, 1915)<ref name="Wegener-1912" /><ref name="Wegener-1966" /> ({{langx|de|"die Verschiebung der Kontinente"}}) and to publish the hypothesis that the continents had somehow "drifted" apart. Although he presented much evidence for continental drift, he was unable to provide a convincing explanation for the physical processes which might have caused this drift. He suggested that the continents had been pulled apart by the [[Centrifugal force (fictitious)|centrifugal pseudoforce]] ({{lang|de|Polflucht}}) of the Earth's rotation or by a small component of astronomical [[precession]], but calculations showed that the force was not sufficient.<ref name="PlateTectonics-2011" /> The {{lang|de|[[Polflucht]]}} hypothesis was also studied by [[Paul Sophus Epstein]] in 1920 and found to be implausible.