Some call him Darwin’s Rottweiler. A man of slight build, wispy silver hair and round spectacles, evolutionary biologist Richard Dawkins did not earn the fierce nickname for his appearance. He earned it for his vigorous advocacy of Darwin’s theory of evolution by natural selection as indisputable scientific fact.
“We have a war on our hands,” the best-selling author said with characteristic conviction, to open his recent speech at the New York Academy of Sciences. A crowd of about 200 eagerly listened to a chapter-by-chapter description of his new book, The Greatest Show on Earth: The Evidence for Evolution—a book Dawkins hopes will arm the defenders of evolution against those who claim it’s “only a theory.”
The question of whether evolution is a theory or fact is not a mere semantics game. It’s so important to the public, to scientists and to Dawkins himself, that it dominates the first chapter of The Greatest Show on Earth. To emphasize evolution’s certainty, Dawkins’s new book even suggests borrowing the word ‘theorem’ from mathematics—meaning a proven statement—and changing its spelling to ‘theorum,’ thus christening evolution anew.
During the question and answer session at the Academy, a young man approached the microphone to ask Dawkins for his response to a New York Times review of his book. In the review, science reporter Nicholas Wade criticized Dawkins for stubbornly calling evolution a fact, arguing that evolution is—and can only be—a theory. “Because the word ‘theory’ is so wantonly misunderstood by lay people,” Dawkins answered the young man, “we are better off using a word that ordinary lay people actually understand”—the word ‘fact.’
Open just about any biology textbook and you will read the following: Evolution is both fact and theory. The fact of evolution is that populations of living things change over time, both in their genes and in their observable traits: this has been confirmed by countless observations in nature and experiments in the laboratory. The theory of evolution refers to scientific explanations of how exactly populations of organisms change over time. This is analogous to gravity as both fact and theory. The fact that objects with mass attract one another has always been true—apples have always fallen to the earth—but the explanations for this phenomenon, the theories of gravity provided by Galileo, Newton and Einstein, have changed throughout the history of science.
Richard Lenski—an evolutionary biologist at Michigan State University renowned for his ongoing evolution experiment with the bacterium E. coli—confirmed via e-mail that he thinks of evolution as both scientific theory and fact. However, Lenski also sees Dawkins’s point: “I think that Professor Dawkins seeks to emphasize the facts of evolution because so many non-scientists are confused about the difference between a robust, coherent, consistent, and well-supported scientific theory, like evolution, and the informal sense of a theory as some sort of hunch or even guess. So it’s a matter of the best way to educate people, and that depends on the audience. I agree with Professor Dawkins that scientists need to emphasize the ‘incontrovertible fact’ of evolution for many non-scientists.”
For many scientists, this lack of confidence in the common reader is justified. There is substantial evidence for an alarming level of scientific illiteracy in the world, particularly in the United States—a fact Dawkins loves to reiterate. “I shall be using the name ‘history-deniers’ for those people who deny evolution: who believe the world’s age is measured in thousands of years, and who believe humans walked with dinosaurs,” he writes in his new book. “To repeat, they constitute more than 40 percent of the American population.”
According to a 2009 Gallup poll, only 39 percent of Americans say they “believe in the theory of evolution,” 25 percent confirm they do not believe in evolution, and 36 percent don’t have an opinion either way. Proponents of intelligent design—who assert that natural selection cannot explain the complexity of human beings and many other life forms—routinely slight evolution as a mere ‘theory’ despite overwhelming scientific evidence demonstrating it’s far far more than some hunch.
Acknowledging this widespread misunderstanding, are public intellectuals like Dawkins really justified in the construction of a deliberate oversimplification, a convenient white lie for all those “non-scientists” and “ordinary lay people” out there? Is it really so difficult to grasp that evolution could be both fact and theory?
There is a great paradox here. Dawkins—who recently retired as Oxford University’s Simonyi Professor of the Public Understanding of Science—has been consistently praised for communicating science to the public in lucid, engaging and intelligent prose. In a series of wildly popular books he has coined more useful and elaborate metaphors—like the selfish gene, extended phenotype and blind watchmaker—than perhaps any other living science writer. He is known for his insistence on writing about important and complex subjects to as large an audience as possible, refusing to dumb down his material.
Despite this, Dawkins is adamant that evolution should be taught as fact and not as theory because he fears too many readers are too ignorant and weak-minded to understand how evolution could be both a theory and fact. As he wrote in the 2005 issue of Natural History Magazine, “Evolution is as much a fact as the heat of the sun. It is not a theory, and for pity’s sake, let’s stop confusing the philosophically naive by calling it so. Evolution is a fact.”