How Science Is Done: Upsetting Applecarts
Hardly a week goes by without some scientific finding upsetting an applecart – a long-held belief. Often, those beliefs are scientific theories taught in textbooks by science professors. Defenders of science say that this is the way science works. It’s a self-correcting process, they argue; it’s to be expected that new data will lead to adjustments to theories. Is that true, or a marketing spin? How would anyone tell? Some examples might help. Here are some recent scientific applecarts that have been upset, according to the news and science journals.
- Standard candles – Not: Supernovas are the standard candles astronomers use for measuring vast distances in space. At first there was one type, then two. Then astronomers found sub-types within those. Now, according to Space.com, “Two faint supernovas unlike any star explosions ever seen before may have exploded in the same way, or they may differ, but in either case are breaking down categories that distinguish one type of stellar death from another.”
- Water from the rock: Numerous TV documentaries about the history of Planet Earth have shown the oceans coming special delivery from comets. Now, Science Daily is claiming that a new study using silver isotopes “indicates that water and other key volatiles may have been present in at least some of Earth’s original building blocks, rather than acquired later from comets, as some scientists have suggested.” But then, that explanation conflicts with dating of Earth’s crust from hafnium and tungsten. To solve the puzzle, the scientists appealed to a model of planet formation called “heterogeneous accretion,” the article said. This solution ads whatever hoc is necessary to get the two results together.
- Insights into speciation, or outsights? Science Daily reported on work by Jeffrey Feder at U of Notre Dame that contradicts a “prevailing assumption” about speciation. His work “conflicts with current thinking” and he claims that “past work on the genomics of speciation lacked experimental data” despite being the main subject of Charles Darwin’s book 150 years ago.
- Back to the Easter Island drawing board: You know those roads on Easter Island? They weren’t for transporting the large statues (moai). They were built for ceremonial purposes, reported PhysOrg. “The find will create controversy among the many archaeologists who have dedicated years to finding out exactly how the moai were moved, ever since Norwegian adventurer Thor Heyerdahl first published his theory in 1958.” This team accused Heyerdahl of being “so swayed by his cast iron belief that the roads were for transportation – he completely ignored them.” But then, are we sure about today’s claims? Dr. Colin Richards said, “The truth of the matter is, we will never know how the statues were moved.”
- Dinosaur demotion: A dinosaur got demoted to primitive pre-dinosaur reptile. According to Science Daily, Azendohsaurus madagaskarensis is not a dinosaur, and never was a dinosaur. It’s now “a member of Archosauromorpha, a group that includes birds and crocodilians but not lizards, snakes, or turtles.” They figured this out by analyzing the whole skull, not just the jaws and teeth.
John J. Flynn, curator in the Division of Paleontology at the American Museum of Natural History, commented on the reclassification and reinterpretation of this specimen. “This is the way science works,” he said. But in the next breath, he revealed that the new interpretation drew on a theory-rescuing device called convergent evolution – explaining similar features in unrelated lineages by saying they both hit on the same solution independently. “As we found and analyzed more material, it made us realize that this was a much more primitive animal and the dinosaur-like features were really the product of convergent evolution,” he said. As if to take the edge off that line, his colleague Andre Wyss added a cheerful note: “In many ways Azendohsaurus ends up being a much more fantastic animal than if it simply represented a generic early dinosaur.”
Behind him, though, was a can of worms the reclassification opened. Archosaurs were thought to be primarily carnivorous before now. “Now there are many more cases of herbivorous archosaurs.” Wynn said. “We are rethinking the evolution of diet and feeding strategies, as well as the broader evolution of the group.” See also the Science Daily article.
- Two inflations are better than one: Inflation theory was invented in the early 1980s to solve some conundrums in cosmology. Since the idea caught on, it has undergone several transmogrifications. Now, there is apparently a need for a “second inflation” reported Rachel Courtland in New Scientist. Some scientists at the University of Heidelberg have brought in a “little inflation” to cover up additional conundrums caused by the first inflation. The idea has the sound of epic myth, or at least of a whoosh of hand-waving. Last sentence: “It just shows that the story might not be as simple as we think.”
- Google lab: Citizen scientists can perform their own experiment by doing a search on science news sites for the phrases, “than thought” and “than previously thought”. For instance, PhysOrg reported this week that scientists now believe “The Earth’s mantle flows far more rapidly around a sinking tectonic plate than previously thought, according to new computer modeling by UC Davis geologists.” (Ditto on Live Science.) A quick search on the CEH search bar turned up 130 hits on these phrases used over the years. Variations of the phrase can add to the collection, like this one on Science Daily about genetic secrets that are coming to light and changing views about “genomic dark matter” that “were once thought of as nothing more than ’junk DNA.’” The phrases suggest the sound of applecarts turning over.
Upsetting applecarts is the way science is done, we are told. Hopefully quite a few of them are getting upset from upside-down or sideways into the right-side-up position. If the total number of applecarts in the right-side-up position is increasing over time, defenders of scientific progress have a case. They are clearly right for the instances where practical payoffs are visible to everyone: either a rocket gets to a planet, or it does not; either a signal makes it across the ocean, or it doesn’t. But for scientific theories with no clear payoff, like theories about stellar life cycles, planet formation, black holes and evolutionary common ancestry, how can anyone tell if scientists are fixing more applecarts than they are turning upside down? What is the metric to show they are faring better than a randomly-selected population of clever storytellers could do, given each had a fairly good understanding of the data and physical parameters involved?
In the early days of the scientific revolution, science was not a profession – it was an avocation. Many early scientists earned degrees, and some taught in universities, but many did their experimental work as a hobby because they loved nature, they loved truth, and wanted to figure things out (browse our online biographies and see). Undoubtedly many in the scientific community maintain that idealism, but there are good reasons to doubt it is universal. The professionalization and institutionalization of science has led to some distasteful consequences: tenure, political groveling for funding, good-old-boys clubs, networking, going along to get along, and more (see lists in the 05/13/2010 and 04/02/2010 commentaries). What motivation do some career scientists have to “get the world right”? They’ve got tenure; they’ve got a grant; they’ve got grad students they have to keep busy doing something; they have the respect of their peers. Like Pilate, they can sneer, “What is truth?”. That’s of little concern in the humdrum of keeping the status quo going, looking busy, dealing with each year’s batch of students, and pumping out an occasional paper with grad students doing the hard work. They know the news media will pick up whatever they say as the latest manna from heaven, a breakthrough that sheds light on whatever and brings us Understanding. You might enjoy browsing through PhD Comics for a humorous inside look at academia. It’s to the idealism of science what Dilbert is to free enterprise.
Happily, many scientists are noble-minded, motivated, serious-minded people of integrity. But they are that way in spite of the many distractions that pull them toward mediocrity or business as usual. Announcing each finding as a revelation that overturns previously-held beliefs plays on the short memories of people. In the short term, it sounds like scientists are making progress. It keeps hope alive that science is converging on the truth about the world. We must not be so na�ve as to think that is necessarily true. Like our commentaries have said, not all motion is progress; sometimes it is just commotion – in this case, turning applecarts upside down, only to turn other ones right-side up, with no net gain in upright carts, but a lot of spilled apples.
One area where science can contribute to progress is in the collection and refinement of raw data. Speculation thrives in the absence of data. Space missions like Cassini, Herschel and MESSENGER, orbiters like Aviris and MLS that refine our measurements of climate, the Human Genome Project and mapping genomes of other organisms, deep sea submarine robot explorations, ever-increasing resolution in microscopy – these at least provide the detail that can constrain speculation. We sometimes confuse progress in data collection with progress in scientific understanding. They are not one and the same. In the recent Titan story (05/16/2010), we saw that Cassini has mapped 22% of Titan’s surface with radar – a fantastic scientific achievement. It does not necessarily follow that scientists understand how Titan formed or how old it is. What the data collection does is put some welcome shackles on the imaginations of storytellers. With fewer applecarts to upset, and more apples in the bag, hopefully there will be less moldy applesauce on the ground.