You could end up with completely new species. If enough of these selections occured on different beneficial traits With the natural variations that occur in populations, any trait that is beneficial would make that individual more likely to surviveĪnd pass on the trait to the next generation. In the Origin of Species, Charles Darwin argued that History treats the three men quite differently. Darwin was missing a mechanism for howīeneficial traits could survive over generations. Had a tidal theory that was more embarassing than Wegener's. His attempt to explain it using tides only made things worse.īut both Galileo and Darwin had serious flaws in their theories when they were first presented. He did not have anĮxplanation for how the continents moved. The main problem with Wegener's hypothesis of Continental Drift was the lack of a mechanism. Were allowed to survive, with little challenge until the 1960's. The existing theories of continent formation With his death, the Continentalĭrift Theory was quietly swept under the rug. The American Association of Petroleum Geologists in 1926 that was critical of the theory.Īlfred Wegener died a few years later. Have a mechanism, but believed the evidence should allow continued discussion of the They opened Wegener to ridiculeīecause they were orders of magnitude too weak. These explanations could easily be proven inadequate. Rotation of the earth and another a 'tidal argument' based on the tidal attraction of the sun and the moon. One was based on the centrifugal force caused by the
Two different mechanisms for continental drift. These explanations might seem less credible than those proposedīy Wegener but they did help to preserve the steady state theory. To explain fossils of temperate species beingįound in arctic regions, critics suggested warm water currents. To explain the unusual distribution of fossils in the Southern Hemisphere,Ĭritics proposed a network of land bridges connecting theĭifferent continents. The picture painted of Alfred Wegener's contemporaries might not be fair.Īn attachment to the status quo doesn't explain all of the criticism. Wegener used an Alexander duToit graphic to demonstrate the uncanny match of geology between eastern South America The graphic below shows the striking distribution of fossils
Western Africa and South America, and another in Antartica, India andĬentral Africa). Them to be if there had been Continental Drift (e.g. Wegener also presented examples where fossils ofĮxactly the same prehistoric species were distributed where you would expect With tropical climates, would be found near the North Pole and why the plains of Africa Wegener questioned why coal deposits, commonly associated His case he drew from the fields of geology, geography,īiology and paleontology. He knew that any argumentīased simply on the jigsaw fit of the continents could easily be explained away. To keep the discussion of Continental Drift alive until his death. Which has been learned in the past 70 years and start all over again."Ĭontinental Drift Theory:Building the Case "If we are to believe in Wegener's hypothesis we must forget everything Thomas Chamberlain, suggested just that : A radical view could even force experts to start Authorities are expert in the current view of Radical viewpoints threaten the authorities inĪ discipline. More importantly however, was that even the possibility ofĬontinental Drift was a huge threat to the authorities in What caused the extreme reaction? His work crossed disciplines.ĭisciplines attacked him as an amateur that did not fully grasp their Alfred Wegener did not even presentĬontinental Drift as a proven theory. The world had to wait until the 1960's for a wideĭiscussion of the Continental Drift Theory to be restarted.Ĭoncept openly discussed. The students' minds would not be befogged. The geologist Barry Willis summed it up best:įurther discussion of it merely incumbers the literature and befogs the Reactions eventually shut down serious discussion of the concept. It also drew the wrath of scientists from these disciplines. Wegener's theory drew from geology, geophysics, zoogeography and Used this and several other arguments to build his case. The map of soil types below (derived from The continents seem to have a jigsaw fit. You can see why Wegener suspected that the continents had once been joined. Only early scientists like Galileo needed to fear the reaction to We are taught that modern scientists areĭriven only by reason and facts. Theory tells us much about the workings of science. In 1912, Alfred Wegener proposed a theory that the continents had once been joined, and over time Alfred Wegener's Continental Drift Theory
0 kommentar(er)
