Wegener and Galileo

Wegener and Continental Drift

How we interpret the science of centuries past cannot be separated from our view of modern science. The danger is that this view may be based on a stereotype. A common stereotype of a scientist is that of a rational professional that evaluates new ideas based only on an objective evaluation of data. This would leave the impression that, unlike early scientists, modern scientists proposing radical new ideas do not need to fear the reactions of those entrenched in the existing system. Alfred Wegener is one modern scientist amongst many that demonstrate that new ideas threaten the establishment, regardless of the century.

Alfred Lothar Wegener was the scientist who championed the Continental Drift Theory through the first few decades of the twentieth century. Simply put, his hypothesis proposed that the continents had once been joined, and over time had drifted apart. The jigsaw fit that the continents make with each other can be seen by looking at any world map. The image on the left shows the continents of Africa and South America joined together. Clicking on the image will illustrate their drift to their current positions (thanks are due NASA for the original images).

Since his ideas challenged scientists in geology, geophysics, zoogeography and paleontology, it demonstrates the reactions of different communities of scientists. The reactions by the leading authorities in the different disciplines was so strong and so negative that serious discussion of the concept stopped. One noted scientist, the geologist Barry Willis, seemed to be speaking for the rest when he said:

further discussion of it merely incumbers the literature and befogs the mind of fellow students.

Barry Willis's and the other scientists wishes were fulfilled. Discussion did stop in the larger scientific community and students' minds were not befogged. The world had to wait until the 1960's for a wide discussion of Continental Drift to be restarted.

Why did Alfred Wegener's work produce such a reaction? He was much more diplomatic in presenting his theory than Galileo. Although he believed himself to be right and that some of his arguments were compelling, he knew he would need more support to convince others. His immediate goal was to have the concept openly discussed. Wegener did not even present Continental Drift as a proven theory. These modest goals did not spare him. The fact that his work crossed disciplines exposed him to the territoriality of scientific disciplines. The authorities in the various disciplines attacked him as an interloper that did not fully grasp their own subject. More importantly however, was that even the possibility of Continental Drift was a huge threat to the established authorities in each of the disciplines.

One can't underestimate the effect of a radical new viewpoint on those established in a discipline. The authorities in these fields are authorities because of their knowledge of the current view of their discipline. A radical new view on their discipline could be a threat to their own authority. One of Alfred Wegener's critics, the geologist R. Thomas Chamberlain, could not have summarized this threat any better :

"If we are to believe in Wegener's hypothesis we must forget everything which has been learned in the past 70 years and start all over again."

He was right.

In spite of the criticisms from several different disciplines Wegener was able to keep Continental Drift part of the discussion until his death. He knew that any argument based simply on the jigsaw fit of the continents could easily be explained away as a coincidence. To strengthen his case he drew from the fields of geology, geography, biology and paleontology. Wegener questioned why coal deposits, commonly associated with tropical climates, would be found near the North Pole and why the plains of Africa would show evidence of glaciation. Wegener also presented examples where fossils of exactly the same prehistoric species were distributed where you would expect them to be if there had been Continental Drift (e.g. one species occurred in western Africa and South America, and another in Antartica, India and central Africa) [_1_] .

After Wegener died, his Continental Drift Theory was quietly swept under the rug. There were problems with his theory; he did not have a credible explanation for how the continents would move. But if his theory had problems, the holes in the then current theories were even larger. The odds against parallel evolution occuring on different continents resulting in exactly the same species are astronomical. One alternative explanation for the anomalies Wegener presented was that there had been an ancient land bridge between South America and Africa. But this was even less believable than continental drift. With the Continental Drift Theory out of the way, the existing theories of continent formation, were able to survive, with little challenge until the 1960's.

If one ignores the fact that even modern scientists will resist radical new ideas it is much easier to interpret historical events according to the conflict hypothesis. The Galileo soundbites (see The Galileo Soundbite) typically use this approach. These soundbites often portray all of Galileo's problems as a simple clash with the church, ignoring all other explanations. This simplistic analysis denies the possibility that some events might be explained as the resistance commonly experienced by scientists proposing radical new ideas, some might be legitimate scientific criticism of Galileo's arguments (see Stellar Parallax) and that some might be a dogmatic reaction by church officials.

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