The (non)relationship between “believing in” evolution and being engaged by evolutionary science

Are Americans who “disbelieve in” human evolution as likely as those who “believe in” it to be interested in a science documentary on our species’ natural history? Would they accept the evidence in such a documentary as valid and convincing?

“No” and “no” would seem to be the obvious answers.  It’s not as if those who reject human evolution just haven’t been shown the proof yet. However skillfully presented, then, another exposition of evolutionary science, one might think, would be more likely to antagonize them than to pique their interest.

But Study 1 in CCP’s Evidence-based Science Filmmaking Initiative suggests that things aren’t that simple.

The study involved a nationally representative sample of 2500 U.S. adults.  In line with national survey findings that haven’t changed for decades (Newport 2014), about 40% of the subjects selected “false” in response to the survey item “Human beings evolved from an earlier species of animal.”

Study subjects were instructed to view as much or as little as they chose of a 10-minute science documentary segment.  The segment was excerpted from Your Inner Fish, an award-winning documentary on evolution that was produced by ESFI collaborator Tangled Bank Studios and that was broadcast on PBS in 2014. The excerpt in question examined the origins of color vision in humans.

The study also measured subjects’ science curiosity and science comprehension. Both of these dispositions were positively correlated with subjects’ acceptance of evolution. But the strength of the relationships was quite modest .  Among those who “believed” in evolution and among those who did not, there were ample numbers of study subjects high in science comprehension and science curiosity, and ample numbers of people who were high in neither.

Unsurprisingly, those subjects who ranked highest in science curiosity were substantially more engaged by the segment.  The more curious subjects were, the more likely they were to watch all or a substantial portion of it; to report finding it interesting; and to supply the information necessary to receive free access to the remainder of the documentary (responses aggregated to form an “Engagement Index”).

The intensity of the relationship between curiosity and engagement was no less pronounced, moreover, in subjects who said they did not “believe in” evolution than it was among those who said they did.  Low-curiosity  evolution “disbelievers” were in fact slightly less engaged than low-curiosity “believers.”  But neither of those low-curiosity subgroups was nearly as engaged by the clip as were evolution “nonbelievers” who scored high on the science curiosity scale.

This is evidence, then, that yes, an evolution “nonbeliever” can enjoy an evolution-science documentary—one that uses experiments on monkeys no less to support inferences about the impact of random mutation, natural selection, and genetic variance on modern humans’ perception of color.

How much an evolution “nonbeliever” will enjoy this documentary depends, the study suggests, on exactly the same thing that an evolution “believer’s” level of enjoyment does: how motivated he or she is to seek out and consume information on science for personal satisfaction–or in a word, how curious that person is about science.

Can an evolution “nonbeliever” find the evidence presented in such a documentary both valid and convincing?

The answer to this question is also “yes”—particularly if he or she is generally curious about science.

A low-curiosity evolution “nonbeliever” was about as likely to disagree as he was to agree that the clip was “convincing,” and that it “supplied strong evidence of how humans acquired color vision.”  But the probability a high-curiosity “nonbeliever” would agree with these characterizations of the validity of the information in the segment was well over 75%.

Note, though, that the curious “nonbelievers” who indicated that they found the evidence “strong” and “convincing” did not “change their minds” on human evolution.

Is that surprising? It won’t be to anyone familiar with empirical study of the relationship between professions of “belief” in evolution and comprehension of science.

That research consistently finds no correlation between how people respond to “true-false” human-evolution survey items and their ability to give a cogent account of natural selection, genetic variance, and random mutation (Shtulman 2006; Demastes, Settlage & Good 1995; Bishop & Anderson 1990).

Researchers also find that students who say they don’t believe in evolution can learn these important insights just as readily as those who say they do believe in it—as long as the teacher doesn’t make the mistake of conveying that the point of the instruction is to extract a profession of “belief” from the former, a style of pedagogy that needlessly pits students’ interest in learning against their interest in being faithful to their cultural identities (Lawson & Worsnop 1999).

What people say they “believe” about human evolution doesn’t indicate what people know; it expresses who they are, culturally speaking (Long 2011).

Professing rejection of evolution coheres with a cultural style that features religiosity (Roos 2012). It is precisely because the answer “false” signifies their defining commitments that individuals with this identity balk when educators make the mistake (itself a sign of inattention to empirical research) of conflating transmission of knowledge with extracting professions of “belief” in it.

When put in the position of having to choose between being who they are and expressing what they know, free, reasoning people understandably opt for the former (Hameed 2015). Indeed, they can be expected to dedicate all of their reasoning proficiency to doing so: the higher the science literacy score of someone who subscribes to a religious cultural identity, the more likely he or she is to respond negatively to the “true-false” survey item “human beings evolved from an earlier species of animal” (Kahan 2015).

Our study captured this form of of identity-protective cognition, too.

Again, science curiosity was positively correlated with levels of engagement and with levels of perceived validity for both evolution believers and evolution nonbelievers.  But this was not the case for science comprehension: as subjects’ scores on the Ordinary Science Intelligence assessment test (Kahan in press; Kahan, Peters et al. 2012) increased, evolution believers became more engaged and more convinced by the clip, while evolution disbelievers became less so.

This result was driven by the negative reactions of evolution nonbelievers who were simultaneously high in science comprehension and low in science curiosity. These study subjects were by far the least engaged by the clip and the least likely to view the evidence it presented as valid.

Nonbelievers who scored high on both the science curiosity and science comprehension scales, in contrast, were highly engaged by the documentary segment and highly likely to deem it a strong and convincing account of the origins of human color vision.

People use their reason for multiple ends. One of these is to form the dispositions and attitudes that enable them to reliably experience and express their commitment to a shared way of life.  Another of these is to attain goals—from personal health to professional success—that can be effectively achieved only with what science knows (Kahan 2015).

People who are curious about science have a goal that those who aren’t curious don’t: to satisfy their appetite to understand the insights generated by use of science’s signature methods of observation, measurement, and inference. EFSI Study 1 shows that such a person can satisfy that goal by enjoying a skillfully made science documentary about evolution even if she has an identity that is itself enabled by professing “disbelief” in it.

In this respect, the results of the study are in line with those that show that individuals who hold a religious identity associated with disbelief in evolution can still learn what science knows about the natural history of human beings and, if they choose, even use that knowledge to engage in activities, such as the practice of medicine or scientific research, that are uniquely enabled by such knowledge (Lawson & Worsnop 1999; Everhart & Hameed 2013).

People who are low in science curiosity can be expected to engage information on it for one purpose only: to be the sorts of persons, culturally speaking, enabled by their respective states of “belief” or “disbelief.”  Making use of information for that end is another one of things people can do even better if they possess the sort of reasoning proficiency associated with high science comprehension.  Accordingly, individuals who scored high in science comprehension but low in science curiosity (the two dispositions are only weakly correlated) predictably formed attitudes—of “engagement” and “acceptance”—that accurately manifested their cultural identities.

What to make of all this?

Well, for one thing, it is very much worth acknowledging that this interpretation of the data from ESFI Study No. 1, like all interpretations of any data, is provisional.  Additional studies, additional evidence might well furnish grounds for revising this understanding.

But it’s also very worth pointing out that the engagement enjoyed by science-curious evolution “nonbelievers,” as well as the experience of edification reflected in their response to the study’s “accuracy” items, belies the simple—indeed simplistic—picture of how those who profess any particular “position” on evolution feel about science.

In particular, it is wrong to infer that those who profess nonacceptance necessarily lack either the desire to know or the capacity to experience awe and wonder at the knowledge human beings have acquired through science, including the astonishing insights into their own natural history.

Because science curiosity does not discriminate on the basis of cultural identity, it would be a mistake for anyone who is genuinely committed to communicating science in culturally pluralistic society to adopt a style of  discourse that forces curious, reflective people to choose between  satisfying their appetite to know what’s known to science and being the sort of person that they are.


Bishop, B.A. & Anderson, C.W. Student conceptions of natural selection and its role in evolution. Journal of Research in Science Teaching 27, 415-427 (1990).

Cultural Cognition Project, Evidence-based Science Filmaking Initiative Study No. 1 (2015).

Everhart, D. & Hameed, S. Muslims and evolution: a study of Pakistani physicians in the United States. Evolution: Educ. & Outreach 6, 1-8 (2013).

Hameed, S. Making sense of Islamic creationism in Europe. Public Understanding of Science 24, 388-399 (2015).

Kahan, D.M. Climate-Science Communication and the Measurement Problem. Advances in Political Psychology 36, 1-43 (2015).

 Kahan, D.M. “Ordinary Science Intelligence”: A Science Comprehension Measure for the Study of Risk and Science Communication. J. Risk Res. (in press).

Kahan, D.M., Peters, E., Wittlin, M., Slovic, P., Ouellette, L.L., Braman, D. & Mandel, G. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Climate Change 2, 732-735 (2012).

Long, D.E. Evolution and religion in American education : an ethnography (Springer, Dordrecht, 2011).
Lawson, A.E. & Worsnop, W.A. Learning about evolution and rejecting a belief in special creation: Effects of reflective reasoning skill, prior knowledge, prior belief and religious commitment. Journal of Research in Science Teaching 29, 143-166 (1992).

Newport, F. In U.S. 42% Believe in Creationist View of Human Origins. Gallup. (June 14, 2014),

Roos, J.M. Measuring science or religion? A measurement analysis of the National Science Foundation sponsored science literacy scale 2006–2010. Public Understanding of Science  (2012).

Shtulman, A. Qualitative differences between naïve and scientific theories of evolution. Cognitive Psychology 52, 170-194 (2006).

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