In the inaugural issue of RNCSE, Alters (1997) proposed that the goal of evolution education should be to teach students to believe in evolution. He argued that educators have resisted teaching evolution with the goal of student belief on the basis of five misconceptions. These are (Alters 1997: 16):
- "belief" means little more than personal convictions — no empirical evidence;
- "belief" is never a goal in public education;
- evolution has little empirical evidence;
- belief cannot be assessed, therefore it does not belong as an educational goal;
- teaching evolution with belief as a goal is tantamount to
Although he offers sound arguments to refute misconceptions (2) and (4), Alters's analyses of misconceptions (1), (3), and (5) need further examination. The issues regarding the teaching of evolution in public schools with diverse populations are much more complex. We must avoid the temptation to teach evolution in a didactic, authoritarian manner regardless of the nature of the student population and their prior beliefs — an approach that would be detrimental to the goal of scientific literacy for all (American Association for the Advancement of Science 1990). It is time to revisit these issues and explore them in the context of current efforts in science education reform and what we know about how students learn. A thorough analysis of the situation with an eye toward making instructional recommendations must take into account what we have learned from research into students' pre-instructional beliefs and worldviews.
Use of the word "belief"
In his discussion of the first misconception, Alters contended that the words "believe" and "accept" are essentially synonymous and are used interchangeably by both scientists and Protestant ministers. He also acknowledged that the word "believe" is more often associated with nonscientific uses in the vernacular but dismissed this distinction as unimportant. However, the distinction between the words "believe" and "accept" should not be merely dismissed as semantics in the context of teaching about evolution.
The choice of words teachers use when discussing evolutionary theories and the evidence that supports them may be crucial to the students' interpretation of the teacher's instructional intent. The use of the word "belief" often carries with it connotations of acceptance based only on faith or personal opinion. When the subject of evolution is raised, students frequently ask teachers whether they believe in evolution or not. A teacher who simply responds in the affirmative may inadvertently convey an inaccurate view of evolution and the nature of science. Whether intended or not, students may have the impression that the teacher is proselytizing for evolution. It is essential that students understand that acceptance of beliefs in science, unlike in religion, is based upon reliable empirical evidence and sound arguments. The use of the word "believe" by scientists and Protestant ministers may convey vastly different messages depending on the context in which these words are used, and students must be made aware of this distinction.
As Alters correctly pointed out, "What is of importance is on which data and arguments one bases a particular belief or acceptance" (1997: 15). Yet teachers cannot and should not dismiss the different interpretations students may have of the words "believe" and "accept". Consequently, teachers should avoid the careless use of the word "believe" when teaching about evolution and be certain that students are aware that a scientist's "belief" in evolution stems from the examination of, and the acceptance of, the empirical evidence and arguments supporting evolutionary theory. Smith endorses this view when he wrote:
Although the distinction between believing and accepting may be a subtle one for many, it is crucial to understanding the nature of science; moreover, drawing carefully the distinction between belief (or faith) in the absence of objective evidence and acceptance that is based on evidence provides an excellent opportunity for helping students understand what science is (1994: 595).
Evolution has little empirical evidence
Another misconception addressed by Alters is that theories of evolution are supported by little or no empirical evidence. Alters contended that the lack-of-evidence "misconception is generally held by non-biology majors who simply have not been introduced to the voluminous amount of data that support evolution, and/or do not themselves believe evolution occurred" (1997: 16). He echoed the view common to professional scientists that this situation could be remedied simply by teaching evolution as fact.
In fact, this misconception is much more widespread and complex than most of us imagine, and the suggestion that teachers simply teach evolution as fact is unlikely to remedy the situation. The misconception that there is little evidence to support evolution is typically at the root of arguments for equal time for creationism in the classroom, and the wide appeal of such arguments is apparent in the results of a recent Gallup poll, which found that 68% of Americans advocate the teaching of creationism along with evolution in public schools (Gallup News Service 2001). Significant percentages of the American population also prefer the biblical account of creation to evolution, suggesting that religious beliefs are frequently at the root of the lack-of-evidence claims. The situation is clearly much more complex than the fact that students simply have not been exposed to the evidence. Instructional recommendations for dealing with evolution in such a climate must go further than simply recommending that evolution be taught as fact.
There are essentially three problems that arise from such an approach. First, in many instances, science teachers who see evolution as conflicting with their religious beliefs may not present evolution accurately, if they present it at all. Even if the teacher's religious beliefs are not an issue, many science teachers simply have a poor understanding of the factual basis of evolutionary theory (Eve and Dunn 1990; Osif 1997) and many others apparently avoid evolution or de-emphasize it because they fear potential conflict (Scharmann 1993). Some of the problem may be in the scant instruction in evolution that teachers-in-training receive, so they know or understand the subject poorly themselves. Practicing teachers may also need periodic updates on the mass of new scientific discoveries and information that validate evolution.
Second, even when teachers understand evolution and teach it well, students frequently hold misconceptions about evolution that employ teleological and Lamarckian concepts (Jensen and Finley 1997). There is ample evidence in the science education and cognitive psychology literature that pre-instructional beliefs like these are remarkably resistant to change. For instruction to be successful, it must go beyond simply teaching evolution as fact (Chinn and Brewer 1993). Good evolution instruction must engage students in inquiry and provide activities that tend to promote conceptual change (Jensen and Finley 1995; Nickels and others 1996).
Finally, evolutionary theories intersect with deeply held beliefs that constitute students' worldviews (Cobern 1991). Implying that simple exposure to the evidence for evolution will result in conceptual change in students assumes that all students already accept the basic assumptions of a scientifically compatible worldview. On the contrary, students come to class with a wide variety of worldviews — many that are inconsistent with the basic assumptions of a scientifically compatible one. Despite the fact that evolution receives support from a wealth of data in many different disciplines, the evidence for evolution is not the issue for these students. Because of their worldviews, they simply do not believe evolutionary explanations, and since they do not consider evolutionary accounts believable, their interpretation of instructional goals will differ from that of the teacher. Their perception will likely be that a teacher who presents evolution in a didactic, authoritarian manner is proselytizing for evolution.
Taking these differences in worldview into account, Cobern argues that "The acquisition of a scientific viewpoint is not at heart an epistemological issue, nor is it a simple matter of conceptual change" (1991: 179). Thus, establishing an instructional environment for these students that is conducive to learning requires an approach that is akin to "foreign relations" (Hills 1989: 183; Cobern 1995).
Teaching evolution as fact is proselytizing
It is possible that teachers are prevented from teaching students to believe in evolution because of a concern that teachers who teach evolution as fact are proselytizing. Alters argued, "Teachers are not proselytizing students when they attempt to change students' belief from 'arsenic is healthy to ingest' to 'arsenic is dangerous to ingest.' Likewise, teachers are not proselytizing when they attempt to have students believe in the scientific fact of evolution" (1997: 16). Indeed, the US Court of Appeals in Florey v Sioux Falls School District (1980) ruled, in effect, that while the fact of evolution may offend some students and parents, the offense is unintended and unavoidable.
This approach may address the legal and constitutional issues, but it avoids educational issues for students whose worldviews are incompatible with science. A didactic and authoritarian approach has little chance of achieving the goal of student belief. Besides alienating students, the teacher's example is likely to foster misconceptions both about evolution and the nature of science. Cobern similarly criticizes this approach:
The challenge here is disbelief — many students simply do not believe evolutionary accounts of origins. By neglecting this legitimate student concern, the teacher tacitly takes an authoritarian and dogmatic stance with the result that the beliefs of many students, if not most, remain unchanged. Moreover, students also resist conceptual change, and hence their understanding of evolution remains inadequate (1994: 585).
When a teacher presupposes that all students will accept from the outset the assumptions underlying a scientifically compatible worldview, those assumptions become part of what has been referred to as the "hidden curriculum". Kilbourn argues that such an approach circumvents student choice since their awareness that there are other ways to view the world can be blocked. He contended that "such teaching is a morally questionable practice" (1980: 42). In any event, it is highly probable that such an approach will serve only to foster misunderstanding of evolution and nature of science.
Evolution and the nature of science
The failure of many students to understand and accept the fact of evolution is often a consequence of the naïve views they hold of the nature of science, which may be largely a result of the way science is presented in textbooks and in classroom discourse (Toumey 1996; McComas 1998). Many students believe that the business of science is to discover knowledge using a special method that leads to fundamental, unchanging truths that must be accepted with certainty by the scientific community (McComas 1998). In the public eye, the prestige and authority of science buttress scientific conclusions "because science is widely believed to transcend the social forces that obviously shape other human institutions, such as politics or religion. Science is believed to be, in a word, 'objective'" (Toumey 1996: 6).
According to this naïve view, the key to the unique success of science at producing true knowledge is "The Scientific Method", which, on the standard account, involves formulating hypotheses, making predictions, and then going into the laboratory to perform the crucial experiment (Gould 1980). In this parody of scientific methods, if a hypothesis passes the test set up by the crucial experiment, that is, if it is confirmed by direct observation, then it is "proven" and it is considered a fact or a law and it is true for all time.
In contrast, the work of many evolutionary biologists involves the reconstruction of the past. The methods they use do not conform to the standard view of "The Scientific Method". Although they cannot replay the past in order to experiment on and make direct observations of the events, there are methods for reconstructing the past history of life on earth (Cooper in press). The methods and patterns of reasoning resemble those that forensic scientists use to reconstruct a crime scene. Just as forensic scientists can reach conclusions that are reliable enough to convict a suspect of a crime, evolutionary biologists can establish reliable knowledge of the earth's past. Unfortunately, since most nonscientists, largely as a result of their science education in school, place a high priority on direct observation of events that occur during controlled experiments, they question the validity of the historical reconstruction of the past on the grounds that no one was there to see it happen. These critics frequently contend, for example, that since no one actually saw humans evolve from their ancestors, this conclusion may not be true, and, therefore, it is acceptable to believe whatever one wants about human origins.
Because evolutionary biologists employ different approaches to problem solving, "creation scientists" (Morris 1974) and, more recently, proponents of "Intelligent Design" (Johnson 1991) have attempted to characterize evolutionary biology as a philosophy of naturalism rather than a science. Both groups claim that creationism and evolution can be placed on an equal footing with regard to empirical support; therefore, a balanced and fair treatment should give equal time to both sides of the issue.
To a public that misunderstands science, arguments for equal time in the curriculum seem entirely fair and democratic. Any approach to evolution education based chiefly on a claim to scientific authority puts teachers in a weak position to defend against equal time arguments (Cooper 1996) and will lend credence to the misrepresentation of evolution as a philosophy of naturalism. Teachers need to avoid authoritarian instructional approaches that disguise the processes that generate scientific knowledge and give the appearance that they are proselytizing. Such didactic and authoritarian approaches to instruction tend only to reinforce misunderstandings of science.
The only way to confront misunderstandings of evolution and the nature of science is to help students achieve a better understanding of the inquiry methods actually employed by scientists. The NRC's National Science Education Standards characterized scientific inquiry as the "diverse ways in which scientists study the natural world and propose explanations based on the evidence derived from their work" (NRC 1996: 23, emphasis added), clearly rejecting the myth of the Scientific Method. Students' understanding of scientific inquiry must also include methods of historical reconstruction. Gould (1986) argues that historical sciences such as evolutionary biology require a different, though no less rigorous, method in order to reconstruct history. In Gould's view, the elucidation of this historical method was one of Darwin's greatest achievements. In addition to establishing the fact that all life was related by common descent and providing a mechanism for evolution, Darwin also freed the discipline from metaphysical speculation and put it on a firm, empirical base. By first teaching students about scientific methods and the nature of scientific knowledge, biology teachers can provide a framework that will enable students to appreciate evolution as the powerful and unifying theoretical perspective that it is.
Approaches to evolution instruction
How should teachers approach the topic of evolution? Clearly, if we are going to teach students successfully about evolution and have them recognize and accept it as a well-supported scientific theory, then we need to address the widely-held misconceptions students harbor about evolution and the nature of science. One suggestion is to assess students' prior beliefs and modes of thought as a first step in any unit on evolution (Bishop and Anderson 1986, 1990; Nelson 1989; Scharmann 1993; Cobern 1994; Smith 1994; Jensen and Finley 1997). Among these, Cobern (1991, 1994) provides the most thorough treatment of worldview considerations and the potential difficulties that may arise when instruction conflicts with worldview. He cautions that the approach to teaching about evolution should not be scientistic — that is, teachers should avoid adopting a view that the scope of scientific authority is unlimited and beyond reproach (Duschl 1988: 52) or that "science provides the one reliable source of objective knowledge" (Cobern 1994: 585). Cobern recommends beginning instruction in evolution with a classroom dialogue that is informed with the knowledge of the cultural history of Darwinism.
Smith (1994) contends that any classroom discussion that precedes the teaching of evolution, and thus sets the stage for an understanding of evolution as science, should deal with the nature of science and how it differs from religion and other disciplines. He concluded that "evolution instruction is challenging because it is both conceptually difficult and because it may not fit with students' worldviews, histories, and perceptions. Successful instructional planning must take all of these facets into consideration" (Smith 1994: 596).
Clough (1994) agrees with Cobern (1994) and Smith (1994) that potential student concerns about conflicts between science and religion should also be addressed prior to the introduction of evolution in the classroom. He also recommends that teachers (1) distinguish theories of evolution from theories of the origin of life from its inorganic precursors — separate and distinct theories that are frequently conflated by students and the general public; (2) help students to understand the distinction between the use of the word "theory" in science and its use in the vernacular; (3) adopt an instrumentalist perspective with regard to belief in evolution, using the historical example of the use of this approach by Copernicus for heliocentrism and for Kekule in his study of atoms. Finally, and perhaps most important, Clough stressed (4) the need for teachers to respect students' beliefs. If students perceive a lack of such respect from their teachers, it will serve to engender hostility toward science and evolution.
Jensen and Finley (1997) used a historically-rich curriculum and paired-problem-solving to achieve some success in eliminating misconceptions about evolution and the nature of science. They identified three pre-Darwinian theories that were used to make sense of the biological world early in the 19th century. They labeled these teleology, Lamarckian evolution, and natural theology. Because many student misconceptions of evolution are consistent with one of these pre-Darwinian theories, Jensen and Finley reasoned that if they brought these pre-Darwinian theories to the students' attention and then pointed out their flaws, they would be more successful in promoting the development of a Darwinian point of view among students. They reported improved student understanding of evolution using their approach. In addition, they observed an increased use of Darwinian ideas by students and a decreased use of non-Darwinian ideas.
The approaches recommended in these articles enable biology teachers to expose students' prior beliefs and set up conditions that may allow students to examine and contrast those beliefs with currently accepted scientific views. These papers represent only a small sample of the recommendations and activities for teaching about evolution that are available in the literature.
Alters's intent that all students both understand evolution and believe it to be the best explanation for life's unity and diversity is a noble one. After all, he argued that we teach other theories, such as the Copernican theory of the solar system, with the intent that students will both understand and believe them. However, the strategies we adopt must employ recommendations based on an understanding of the complex issues resulting from students' pre-instructional beliefs and diverse worldviews. An authoritarian approach will only serve to polarize religion and science in the minds of students, and foster close-mindedness and resistance from many who will then be ignorant of the historical background and the empirical evidence that have led biologists to the evolutionary point of view.
While we may adopt universal belief as our goal, we must also recognize that, given the diversity of worldviews we find in the typical classroom, the goal may be an unrealizable one. In particular, fundamentalist Christians who insist on a literal reading of Genesis may never find sufficient grounds for a reconciliation of their religious beliefs and evolution (Ruse 2001). The most important issue at stake here, however, is not whether students ultimately accept or reject evolution, but that students develop an accurate understanding of the nature of science and the scientific process, resulting in the improvement in scientific literacy. An education that promotes intellectual maturity and reflective judgment (King and Kitchener 1994) must enable all students to understand and appreciate all perspectives, including the scientific one. Instruction designed to achieve this goal must be informed by the metaphor of teaching science as "foreign affairs" (Hills 1989; Cobern 1995). Even if students ultimately choose to reject an evolutionary view of the world, the ability to "see" from that perspective may promote greater tolerance and understanding as well as greater intellectual maturity. Whether students choose to accept (believe) evolution or not, they must come to understand what science is and understand that evolution is a powerful scientific theory that provides a unifying framework for biology.
Since science — and evolution in particular — is judged not to conflict with the basic tenets of many religions organizations and denominations (Matsumura 1995), most students will find that they can retain their religious beliefs while developing a sound understanding of evolution. Many students may even come to accept (believe) that the evolutionary point of view is the best account of the evidence that we have.