Evolution and Religion: Attitudes of Scottish Bioscience Students to the Teaching of Evolutionary Biology

Evolution Rejection Levels and the Influence of Education

The report of Downie and Barron (2000) on Glasgow level 1 biology students found a nine-year mean of 7.3% evolution rejecters but with a significant downwards trend in the more recent years. Our new data, collected a decade later, indicate no continuation of that trend: a persistent minority of evolution rejecters remains. From an evolution education viewpoint, the encouraging feature of our findings is that evolution rejection is associated with low previous exposure to biology (enrollment in level 1 biology does not require school or college biology as a prerequisite) and with students who do not intend further study in aspects of biology where evolution is a core theme. Comparison with our level 4 students requires some caution: we did not follow the same cohort of students through to level 4 and then re-assess them. However, given our large sample sizes and the fairly stable proportion of level 1 rejecters, the levels 1–4 trend should be meaningful. Overall, there was a substantial reduction in evolution rejection between levels 1 and 4. This was not simply a matter of general maturation since evolution rejection remained fairly high in level 4 students whose courses included little or no evolution, but dropped to zero in students whose courses included post-level 1 evolution content.

Reasons for Accepting or Rejecting Evolution

Evolution accepters mostly chose the option “the evidence is convincing and well supported” as their reason for acceptance, with the proportion increasing from over 70% to over 90% in level 4 students who had studied evolution beyond level 1. Rather a small proportion selected the option “my lecturers have a greater knowledge of the subject, so I accept what has been taught to me,” and an intermediate proportion opted for “no better explanation.” Although Downie and Barron (2000) phrased this question somewhat differently, there has been a shift in this new survey toward “convincing evidence” and away from “no better explanation.”

For level 1 evolution rejecters, the commonest option was the religion-based alternative explanation, but substantial numbers chose “insufficient evidence” (presumably the same evidence that evolution-accepters predominantly found “convincing and well supported”) and significant numbers cited insufficient personal knowledge, especially in 2009–2010. Downie and Barron (2000) again presented this question somewhat differently and found the commonest option the acceptance of a “religious creation account that excludes evolution.” By level 4, our evolution rejection sample size was very small, but the importance of a belief precluding evolution remained the main factor. Our sample size for switching from rejection to acceptance was also small (n = 7), but it is fascinating that these students were less affected by scientific evidence than by a realization that evolution and their religious beliefs were not in conflict.

As Downie and Barron (2000) noted, a worrying feature of these results is that these are science students who are allowing a religious belief to influence their view on a scientific theory. Scientists need to be able to assess evidence objectively, and science education needs to help prospective scientists to understand how science works as a process and to develop their own scientific skills and practices. Blancke et al. (2011) have emphasized that the creationist challenge to evolution has highlighted a deficiency in science education when it neglects to make clear the nature of science as a continuing process. As Williams (2009) has noted, it is not easy to influence beliefs which young people have developed from an early age, even by the presentation of strong evidence. Williams also notes that science education rarely deals well with science as a process, but this is precisely what is needed when preconceptions and mistaken beliefs need to be confronted. Part of the process of science is the historical development of ideas: as Williams notes, this is usually inadequately dealt with in science classes. Few of our level 1 students were able to identify correctly the key dates concerning Darwin and The origin of species.

Where our students stated a religion, Christianity and Islam were predominant, with the proportion of Christians declining and Muslims increasing since Downie and Barron (2000). The proportion of Christians rejecting evolution has increased since 2010 while the proportion of Muslims rejecting has decreased. There has been considerable coverage of the influence of faith-based education on evolution rejection in the UK (Williams 2008), but without a detailed analysis of the school backgrounds of our students, it is not possible to ascribe the causes of the trends we have found. Downie and Barron (2000) noted the high proportion of Muslim rejecters but also that many Muslims were accepters. Burton (2010) has emphasized that in this, as in many other features, Islam is no more a monolithic faith than is Christianity. She particularly contrasted Iran, where evolution is comprehensively taught, with Saudi Arabia where science textbooks devote much space to discrediting evolution. In apartheid South Africa, evolution was excluded from the school curriculum under the influence of the fundamentalist Christian Afrikaans Reformed Church: only since 2008 has evolution entered the curriculum (Abrie 2010).

The proportion of level 1 biology students claiming to hold a religious belief is lower (43% in 2008–2009 and 44% in 2009–2010) than the 59% reported by Downie and Barron (2000). It is worth emphasizing that, although evolution rejection was strongly associated with holding a religious belief, the majority of believers accepted evolution.

Science Skepticism and Beliefs

In considering the reasons for evolution rejection by some students, Downie and Barron (2000) tested the proposition that evolution rejecters are generally skeptical of the claims of science. They found some evidence for this idea: rejecters were more skeptical than accepters of the impact of CFCs and acid rain and the link between smoking and lung cancer. However, the big difference between the groups was on evolution and an evolution-related phenomenon, plate tectonics. This time, the set of propositions we assessed contained both similar and different theories. The smoking–cancer link had high acceptance from both accepters and rejecters with little difference from 2000. As before, the plate tectonics proposition was significantly more accepted by evolution accepters than rejecters. Curiously, Einstein’s energy equation showed the biggest difference between the two groups, due to the low proportion of rejecters who believed this equation to be well established (perhaps reflecting a limited exposure to physics). The climate change proposition showed no difference between the groups, but interestingly, both groups gave this a low level of acceptance, possibly reflecting the high media exposure of climate change skeptics. In the U.S., there is linkage between evolution and climate change rejection (Young 2012), but no evidence of this was found among our students. Overall, there was little evidence from this study that evolution rejection was linked to a generalized skepticism about the claims of science.

Are Evolution Rejectors Simply Poorly Informed?

A possible explanation for evolution rejection in our level 1 students is that they have not had the opportunity to, or taken the trouble to learn much about evolution, i.e., they are poorly informed. We noted earlier that many of the rejecters had not studied biology prior to our level 1 course. Tables 8 and 9 provide support for this explanation. Over 80% of level 1 accepters and all level 4 students identified the correct definition for Darwinian evolution whereas only 30% of level 1 rejectors got this right. Even on the two kinds of creationism, level 1 rejecters were insecure. The question relating to the Darwin 200 celebrations did not require understanding or acceptance of the theory, and there was no difference between level 1 accepters and rejecters (both did poorly). It was encouraging to see an improvement in factual knowledge of Darwin in the level 4 cohort, especially those who had studied evolution in more detail.

Williams (2009) has argued that the low level of acceptance of evolution and ignorance of what the theory actually comprises is largely the result of weak coverage at school which starts too late and which is poorly delivered. He recommends that evolution should at least be introduced as part of primary school science, but Blancke et al. (2011) caution that the process of child cognitive development suggests that evolution is a concept better tackled once children are over ten years old.

Acceptance of the Different Propositions of Evolutionary Theory

Evolution is a multi-proposition theory (Futuyma 1998), and some evolution rejecters accept some aspects. In particular, microevolution within species is so self-evident that many creationists accept it while rejecting other aspects (for example, see Yahya 2006). Downie (2004a) reported that all but one of a group of 24 first-year medical students who rejected evolution accepted that natural selection operates within species. Speciation and the descent of human beings from a common ancestor with chimpanzees are generally known to be much more problematic. To what extent were these differences reflected in our surveys? The only group showing a low acceptance level for microevolution was the Level 1 rejecters. Both low- and high-level 4 students showed higher levels of acceptance than level 1 accepters. We regard these results as showing that the better-informed students are, the more likely they are to accept microevolution. For macroevolution and human origins, the influence of enhanced knowledge is again evident in the comparison between level 1 accepters and level 4 high students, with level 4 low students also showing higher levels of acceptance. As expected, these two propositions are more problematic for evolution rejecters, but it is surprising to find that a proportion of level 1 rejecters actually accept all three propositions: it is unclear from this what they think they are rejecting, and this question remains to be explored.

The Importance of Language: Acceptance or Belief

In our surveys, and in those by Downie and Barron (2000), the question we asked was worded as “Do you accept that…”, rather than “Do you believe that….” In our view, “belief” is inappropriate for questions about science. Williams (2009) and Moore (2009) both agree on this point but note that general public surveys of attitudes to evolution often do use the word “believe.” It is unclear how many people in a general public survey, or even a science student survey, would appreciate this distinction. “Acceptance” ought to imply knowing and understanding the evidence, but how many of us can take this position on more than a few scientific theories? Mostly, we accept what authoritative scientists, experts in a field, tell us. In this respect, those students who told us that their reason for accepting evolution was the greater knowledge of their lecturers were possibly the most honest. Such a response may be more akin to a belief than the process of objectively weighing up scientific evidence. The low acceptance levels of global climate change by our students may reflect something similar: students are unlikely to have considered the evidence themselves; their attitudes therefore reflect the confusion generated by media exposure of a minority of vocal rejecters.