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The fear of catastrophe, numbers, and ridicule

In Dinosaurs Rediscovered: The Scientific Revolution in Paleontology, Professor of Vertebrate Paleontology and Paleobiology Research Group (University of Bristol) head Michael J. Benton explains dinosaur evolution and extinction, field methods, and classification systems.

The book has easy-to-digest "how-to" explanations, like how field methods are conducted and how scientists can know what they know, like what ancient climates were like, if dinosaurs were warm-blooded, and the likelihood of a Jurassic Park-scenario happening. (SPOILER ALERT: Not at this time. "The methods can all be identified, but DNA does not survive for long, and so there is currently no prospect of obtaining any dinosaurian DNA" (p. 152).) Benton also gives artful insights into what isn't yet understood, like the purpose of Tyrannosaurus rex's embarrassingly little arms, and how and why dinosaurs could be so big.

My favorite part, and what I'll most likely share with future graduate students, was his opening question: "what is science?" This inquiry comes up repeatedly throughout this book. In science, he said, "proof is never possible, merely disproof" (p. 286). This is because science does break down by simply dislodging a fact. It is built on hypotheses and theories. "I can have many hypotheses about why the dinosaurs died out or why sauropods were so large," Benton said. "Some of these modify into theories when there is a sufficient body of coherent evidence" (p. 286). As an example, he cites the Alvarez model for catastrophic impact at the end of the Cretaceous. Luis W. Alvarez, Walter Alvarez, Frank Asaro, and Helen V. Michel presented the impact theory in their June 6, 1980, paper, Extraterrestrial Cause for the Cretaceous-Tertiary Extinction. This impact theory hinged on increased levels of iridium in deep-sea limestone dating to the Cretaceous-Tertiary extinction, about 66 millions years ago. Iridium is found in minuscule amounts on the earth, but is more abundant in rocks coming from outer space.

When this paper was published, it caused uproar. When he was a student, Benton said, mass extinction was not considered. Dinosaurs' demise was believed to have been gradual. One reason for this was the prominence of seminal teachings like Charles Lyell's uniformitarianism, which assumes that modern natural laws and processes also applied in the past. Catastrophism, one the other hand, was "dangerous, wild, relying on supernatural explanations" (p. 257), and was one of at least a hundred explanations for dinosaur extinction published in scientific journals since the 1920s, along with dietary problems, environmental shifts, arthritis, shrinking brains, and dinosaurs being too weird to evolve. Uniformitarianism held "a tight grip over geology until the 1980s" (p. 257) Benton said.

Another reason for outcry was the source from which the theory was proposed. Experts from other fields, who used more numerical approaches, were less trusted, Benton said. Alvarez was a physicist. In fact, he won the Nobel Prize in Physics in 1968. Geologists and paleontologists alike were defiant of his model. Overall, Benton said geologists' and paleontologists' reasons for rejecting the theory could be summarized in three concepts: Fear of catastrophe, numbers, and ridicule.

These three variables struck me (no pun intended) because of how prominently they influence any number of fields of inquiry. I can envision his description of the impact model and the fear of catastrophe, numbers, and ridicule generating a healthy discussion in just about any graduate-level theory course, journalism and mass communication included. Particularly Benton's argument about the process of theory building: that critics "cannot simply ridicule a particular theory and step back. It's not like politics. The critic must present a more convincing theory that explains the data better than the theory he or she is criticizing. The business of being a scientist is rigorous, and the argument has to consider all the evidence, and weigh up alternative hypotheses in an even-handed way" (p. 287) (italics added).