The website Understanding Evolution, hosted by The University of California Museum of Paleontology, Berkeley, offers its readers numerous helpful resources regarding the science and history of evolutionary biology. The site’s stated goal is to “help you understand what evolution is, how it works, how it factors into your life, how research in evolutionary biology is performed, and how ideas in this area have changed over time.” Among its resources is a list of popular misconceptions about evolutionary theory. In this two part series, we’d like to highlight some of the site’s most helpful responses to these misconceptions. The full list, and many other wonderful resources, can be found at Understanding Evolution.
Misconceptions about Evolution and the Nature of Science
“Evolution is not science because it is not observable or testable.”
This misconception encompasses two incorrect ideas: (1) that all science depends on controlled laboratory experiments, and (2) that evolution cannot be studied with such experiments. First, many scientific investigations do not involve experiments or direct observation. Astronomers cannot hold stars in their hands and geologists cannot go back in time, but both scientists can learn a great deal about the universe through observation and comparison. In the same way, evolutionary biologists can test their ideas about the history of life on Earth by making observations in the real world. Second, though we can't run an experiment that will tell us how the dinosaur lineage radiated, we can study many aspects of evolution with controlled experiments in a laboratory setting. In organisms with short generation times (e.g., bacteria or fruit flies), we can actually observe evolution in action over the course of an experiment. And in some cases, biologists have observed evolution occurring in the wild.
"Evolution is 'just' a theory."
This misconception stems from a mix-up between casual and scientific use of the word theory. In everyday language, theory is often used to mean a hunch with little evidential support. Scientific theories, on the other hand, are broad explanations for a wide range of phenomena. In order to be accepted by the scientific community, a theory must be strongly supported by many different lines of evidence. Evolution is a well-supported and broadly accepted scientific theory; it is not ‘just' a hunch.
For more, see the question "What is evolution?"
"Evolutionary theory is invalid because it is incomplete and cannot give a total explanation for the biodiversity we see around us."
This misconception stems from a misunderstanding of the nature of scientific theories. All scientific theories (from evolutionary theory to atomic theory) are works in progress. As new evidence is discovered and new ideas are developed, our understanding of how the world works changes and so too do scientific theories. While we don't know everything there is to know about evolution (or any other scientific discipline, for that matter), we do know a great deal about the history of life, the pattern of lineage-splitting through time, and the mechanisms that have caused these changes. And more will be learned in the future. Evolutionary theory, like any scientific theory, does not yet explain everything we observe in the natural world. However, evolutionary theory does help us understand a wide range of observations (from the rise of antibiotic-resistant bacteria to the physical match between pollinators and their preferred flowers), does make accurate predictions in new situations (e.g., that treating AIDS patients with a cocktail of medications should slow the evolution of the virus), and has proven itself time and time again in thousands of experiments and observational studies.
"Gaps in the fossil record disprove evolution."
While it's true that there are gaps in the fossil record, this does not constitute evidence against evolutionary theory. Scientists evaluate hypotheses and theories by figuring out what we would expect to observe if a particular idea were true and then seeing if those expectations are borne out. If evolutionary theory were true, then we'd expect there to have been transitional forms connecting ancient species with their ancestors and descendents. This expectation has been borne out. Paleontologists have found many fossils with transitional features, and new fossils are discovered all the time. However, if evolutionary theory were true, we would not expect all of these forms to be preserved in the fossil record. Many organisms don't have any body parts that fossilize well, the environmental conditions for forming good fossils are rare, and of course, we've only discovered a small percentage of the fossils that might be preserved somewhere on Earth. So scientists expect that for many evolutionary transitions, there will be gaps in the fossil record.
For more see out question "What does the fossil record show?"
Misconceptions about the Acceptance and Implications of Evolution
“Evolution is a theory in crisis and is collapsing as scientists lose confidence in it.”
Evolutionary theory is not in crisis; scientists accept evolution as the best explanation for life's diversity because of the multiple lines of evidence supporting it, its broad power to explain biological phenomena, and its ability to make accurate predictions in a wide variety of situations. The vast majority of scientists do not debate whether evolution took place, but they do debate many details of how evolution occurred and occurs in different circumstances. Antievolutionists may hear the debates about how evolution occurs and misinterpret them as debates about whether evolution occurs. Evolution is sound science and is treated accordingly by scientists and scholars worldwide.
For more see the questions "Does thermodynamics disprove evolution?", "How can evolution account for the complexity of life on earth today?" and "How can evolution account for the complexity of life on earth today?"
"Evolution supports the idea that 'might makes right' and rationalizes the oppression of some people by others."
In the nineteenth and early twentieth centuries, a philosophy called Social Darwinism arose from a misguided effort to apply lessons from biological evolution to society. Social Darwinism suggests that society should allow the weak and less fit to fail and die and that this is good policy and morally right. Supposedly, evolution by natural selection provided support for these ideas. Pre-existing prejudices were rationalized by the notion that colonized nations, poor people, or disadvantaged minorities must have deserved their situations because they were "less fit" than those who were better off. In this case, science was misapplied to promote a social and political agenda. While Social Darwinism as a political and social orientation has been broadly rejected, the scientific idea of biological evolution has stood the test of time.
"Evolution and religion are incompatible."
Because of some individuals and groups stridently declaring their beliefs, it's easy to get the impression that science (which includes evolution) and religion are at war; however, the idea that one always has to choose between science and religion is incorrect. People of many different faiths and levels of scientific expertise see no contradiction at all between science and religion.
In fact, science and religion can have a constructive relationship. The majority of scientists during the emergence of modern science in medieval Europe, for example, were devout or conventionally religious. Religious belief, then, can function as a framework within which scientific progress flourishes. Religious belief can also be influenced by science. In the Galileo Affair, scientific evidence of a heliocentric universe caused the church to revisit its interpretation of a part of Scripture.
Oddly enough, some people argue that God’s existence is actually a scientific claim and should be tested like any other. However, God’s existence is not something that can be tested by the scientific method in the same way the existence of postulated new elementary particles are tested in supercolliders. Because science provides knowledge about the natural world, no amount of testing or theorizing could prove or disprove the existence of a supernatural creator. Rather than an empirical claim about nature or its laws, the claim that God exists is a metaphysical one, a statement about what there is, whether it be natural or supernatural.
For more see the questions "What is the proper relationship between science and religion?", "Can scientific and scriptural truth be reconciled?", "What were the initial Christian responses to Darwin?", and "What role could God have in evolution?"