Scientific Fads

Science is a relentless pursuit of truth via evidence, right? Well, more so than most other ways of thinking, but scientists are still human. As explained in my book Scientifically Thinking: How to Liberate Your Mind, Solve the World’s Problems, and Embrace the Beauty of Science (what a pompous title), scientific research is specifically designed to keep human scientists from falling into the common frailties of human thought (I have a chapter about each of them).

One example is that scientists are attracted to fads just like anyone else. Here are some examples:

Before Darwin, evolutionary theories were pretty speculative and justly earned the dislike of scientists. Darwin presented not just evidence for evolution but a mechanism for how it could work. All at once, evolution became a scientific theory. (Some problems, such as the objection raised by Fleeming Jenkin, come out of the woodwork with sometimes wild speculations. Herbert Spencer’s version of evolution was quite different from Darwin’s, and has essentially no supporters today, but it was Darwin who made Spencerism briefly viable. Darwinism also opened the door for the application of evolutionary ideas in the interpretation of human history and the evolution of languages (for example, by John Fiske in his 1883 Excursions of an Evolutionist), and theological applications such as those by Henry Ward Beecher.

Once Koch and Pasteur had proven that the diseases that they studied were caused by microbes, then most medical research (about 1880-1910) focused on microbes. This was before the modern understanding of genetics. At least the focus on microbes was a welcome relief from the older concepts of demons, humours, and vapours. And we continue to be surprised by microbial influences on what we thought were simply metabolic diseases. Some researchers think that plaque buildup in arteries, leading to heart disease, may be a response to bacterial infection, and that antibiotics might be used to treat some cases of heart disease.

For a while, it was a fad for scientists to find microbial causes of every disease. The truth, it turns out, is more complicated.

Another example. When the Alvarezes and colleagues proposed that an asteroid caused the Cretaceous Extinction, the proposal was met with skepticism or worse. But as evidence accumulated, a consilience of independent lines of evidence, everyone was convinced that they were right. It wasn’t long before scientists proposed asteroid causes of other Earth events. Colleagues of Luann Becker proposed that the Permian Extinction was also caused by the asteroid that formed the Bedout Crater. The Alvarez group was able to find the Chicxulub Crater in Yucatan, from 65 million years ago; finding the Bedout Crater from 250 million years ago was not as easy, and this might be the reason the Bedout hypothesis is so weak. 

But then other scientists proposed an asteroid cause of the mass extinction of North American mammals at the onset of the Younger Dryas cooling period. Although not all of the evidence presented by Firestone and colleagues has been discounted, it has not proven convincing enough to change most scientists’ minds, especially since this asteroid would have hit less than 13,000 years ago. Scientists (that is, not including me; I am no expert in this field) still prefer to say that the Pleistocene Extinction was caused by an interaction of global warming after the most recent ice age and overhunting—though neither of these factors could alone explain the extinction. Asteroids were a fad.

As with science, so also with technology. Most agricultural researchers, working in labs well-funded by the government and private industry, have jumped on the bandwagon of GM and claim that world hunger can be solved by genetic modification of crops. There are even more scientists, and they are more certain, since the development of CRISPR enzymes. I am not one of the GM technophobes (though I respect those such as Gary Paul Nabhan who do fear it), but our world food problem is way too complex for genetic modification to solve it and, by concentrating the power of agribusiness, will probably make the problem worse, as I explained in previous essays. Genetic modification, and its detractors, are both fads.

I can only hope that the scientific method will help scientists to avoid the pitfalls of human thinking right when everyone else needs our guidance.