J. KIRK FITZHUGH, PH.D., has been the Curator of Polychaetes at the Natural History Museum of Los Angeles County since 1990. While his research has focused mainly on the study of sea worms from around the world, Fitzhugh’s interests extended to the philosophical foundations of evolutionary biology about a decade ago.
“At the time, there was growing debate about what methods should be used to produce phylogenetic trees—those branching diagrams showing evolutionary relationships,” Fitzhugh says. “Computer programs were becoming more sophisticated and a person could churn out just about any kind of hypothesis he or she wanted. I thought technology was outpacing the philosophical underpinnings of what scientists are trying to accomplish.”
Fitzhugh also started to notice interesting parallels between his research evaluating the philosophy of evolution and the groundswell of attention on intelligent design. In his recent articles, Evolutionary Biology Versus Intelligent Design: Resolving the Issue and The Mechanics of Testing a Theory: Implications for Intelligent Design, he broaches the touchy, tangled schism between evolution and intelligent design with this position: It need not be touchy or tangled in terms of science, because it’s not a scientific debate.
The intelligent design movement grew out of the creationist point of view in the early 1990s, arguing that organisms are so intricately complex, only an intelligent being or force could have been the cause. But many feel that intelligent design does not jibe with how we acquire understanding in science, which relies on well-established procedures that investigate and constantly correct our explanations of the diversity of life.
Fitzhugh believes that intelligent design is seen by some as a viable scientific theory, and an alternative to evolution, because of misunderstandings of the terms “theory,” “hypothesis,” and “fact” and the ways that all fields of science evaluate theories and hypotheses.
Facts are the objects and events that exist around us, which we might observe and experience; a hypothesis is an explanation of some set of facts. For instance, we have the facts that mammals have hair—a set of observations we wish to explain. An evolutionary biologist might then present the following hypothesis: As the result of random mutation, hair originated in the earliest mammals, which were diminutive and likely nocturnal creatures, living among the dinosaurs, and there was a selective advantage to the presence of hair because it ensured a constant body temperature.
But, we can only arrive at such a hypothesis because we apply theories, which are well-established or generally accepted explanatory concepts. Notice that the hypothesis explaining the presence of hair used the theories of mutation and natural selection. Hypotheses suggest to us what might have happened in the past to account for what we observe in the present. Theories, on the other hand, are used to not only guide us in understanding the present by way of the past, but to also anticipate what we might experience in the future. As with any human endeavor, however, hypotheses and theories might be incorrect. So a fundamental part of any field of science is the process of critically evaluating our hypotheses and theories, known as testing.
Having theories that are capable of being tested is what separates scientific and non-scientific approaches to the acquisition of understanding. For instance, the theories of mutation and natural selection have been subjected to testing for over 100 years. Intelligent design, as well as creationism, are theories that are immune to testing according to Fitzhugh; there is no experimental framework by which either can be evaluated. He’s not criticizing a desire to invoke intelligent design or creationism. He’s criticizing the ongoing attempts to associate these approaches with science and science education, because they misrepresent the basic nature of scientific inquiry.
Intelligent design is a theory in its own right, just not a scientific theory—and what is seen as a clash between science and religion is actually no clash at all. Both are realms in which understanding is sought; they are just wholly separate, and independent. Fitzhugh contends that these two realms cannot therefore stand in judgment of one another, as has so often been the case.
“Addressing the fundamentals of evolutionary biology and science are important topics that natural history museums need to convey in order to provide the public with the best opportunity to judge the merits of non-scientific alternatives,” he says. “It is an exciting opportunity for dialogues among scientists and non-scientists alike.”