This study explores three variables and their possible relationship with acceptance of evolution among religious students. These variables are: knowledge of evolution, religious practices, and knowledge of religious doctrine. In addition, we measured changes in the acceptance of evolution following a discussion dedicated to LDS doctrine and evolution.
Overall, students increased substantially in their acceptance of evolution over the course of the semester(see Fig. 3). At the beginning of the semester, only 22.7 % of students were highly supportive (accepting) of evolution, while 39.8 % of students were dismissive (Fig. 2). The remaining students fell into the moderately accepting category. Thus, the BYU student body is representative of the overall US LDS church membership regarding acceptance of evolution (22 % acceptance rate; Miller 2008). While the perceived disagreement between religion and evolution continues, educators should be encouraged by student ability to learn and change perspective. By the end of the semester 56.7 % of students were very highly accepting or highly accepting of evolution, a significant increase of 34 % (p < 0.001) from the beginning of the semester. Thus, even though a low percentage of students initially accepted evolution at a high level, there were even fewer students who dismissed it by the end (see Fig. 2).
We also found that with explicit instruction, there is a significant increase in knowledge of evolution. This is a logical and expected result (Cotner et al. 2009; Kim and Nehm 2011; Moore et al. 2011). In general, students respond well (via increase in knowledge) when evidence of evolutionary theory is provided and specific misconceptions are targeted (Wiles 2014; Moore et al. 2011). Obviously educating students on evolution will improve their understanding of it, but some studies show this is only true for the least religious students (Moore et al. 2011; Kahan 2015; Rissler et al. 2014). Our data show no significant relationship between religiosity and gains in knowledge of evolution. Instead, students made significant gains in knowledge of evolution regardless of religiosity Fig. 3.
Is there a relationship between conceptual understanding of evolutionary theory and acceptance?
Many have found a positive relationship between knowledge and acceptance of evolution (Wilson 2005; Ingram and Nelson 2006; Robbins and Roy 2007), while others have not (Lawson and Worsnop 1992; Crawford et al. 2005; Cavallo and McCall 2008). We found a positive relationship between knowledge of evolution and acceptance of evolution (see Table 3). In addition, as students with an incorrect or limited understanding gained greater competency with the theory of evolution (defined as being able to correctly comprehend major evolutionary tenets) they also became more accepting of it (see Fig. 1a, c).
Is there a relationship between religious commitment (religiosity) and student acceptance of evolution?
Our data show that religiosity does affect their initial willingness to accept evolution. We found a negative relationship between overall religiosity and acceptance of evolution (Table 3). The items used in our measure of religiosity (e.g., frequency of prayer, church attendance, belief in an afterlife, etc.; see Additional file 1: Appendix A) show that religiosity itself may be a causative factor in low acceptance of evolution. These findings are in line with numerous, previous research articles (e.g., Andersson and Wallin 2006; Coyne 2012; Heddy and Nadelson 2013; Rissler et al. 2014). Student religiosity did affect the initial acceptance rate of evolution (Table 3), but it did not hinder students from increasing in acceptance of evolution by the end of the semester. Students who were initially the least accepting of evolution had a significant increase in acceptance. We found that religiosity was a significant positive predictor (p < 0.001) of change in MATE and that the more religious an LDS individual ranked the greater the gains in acceptance of evolution over the course of the semester. Even though we used normalized gains to remove a ceiling effect, it should be noted that it may be that the most religious students were initially the least accepting of evolution and had the most to gain. Nevertheless, although religiosity is a factor in initial acceptance of evolution, it does not prevent LDS individuals from learning or modifying their views.
Does an understanding of LDS doctrine concerning evolution affect acceptance of evolution among LDS students? And Can instructors influence LDS student acceptance of evolution by helping them understand the specific religious doctrine on evolution?
One novel result from this study was that as students learned more about their own religion and its doctrine on evolution, acceptance rates increased significantly (p < 0.001). We found a positive relationship between student initial understanding of the LDS stance on evolution (ULSE) and initial acceptance of evolution (MATE; see Table 3).
We also found that as students with an incorrect or limited understanding of the LDS stance on evolution gained knowledge of LDS doctrine (via class discussion (Fig. 1b). Students who did not participate in a discussion had greater gains in knowledge of evolution but had significantly less gains in acceptance of it (see Fig. 1d). The more misconceptions a student harbored regarding the LDS stance on evolution the less likely they were to accept the theory of evolution. In the control class, students made significantly smaller gains in their understanding of LDS doctrine on evolution (ULSE; Fig. 1b, 1d). Not having a discussion focused on LDS doctrine could have impeded their ability to synthesize their understanding of evolution with LDS beliefs. Interestingly, Masci (2009) found that of the general US public, people who attend worship services more frequently are less likely to perceive faith and science as conflicting forces. In conjunction with Masci (2009), our results suggest that some factors leading to higher acceptance of science could be familiarity with one’s religion (as long at the religion is neutral or supportive to evolution), intellectual engagement and/or theological engagement. We demonstrate that when students recognize that LDS doctrine is neutral towards evolution and are able to actively discuss this point in a classroom setting, they become empowered to form positive viewpoints on evolution.
Longitudinal surveys show that students from both semesters retained the same degree of acceptance of evolution 5–7 months following the end of class, while losing some knowledge of evolution. Nadelson and Sinatra (2010) showed that acceptance of evolution increases even when knowledge does not. We have shown that acceptance can be maintained even while knowledge decreases over time. This makes for potential concern as it seemingly produces students who have an ongoing favorable opinion/acceptance of evolution but cannot recall specific principles that support the theory. We speculate that students may not remember the details of what was being explained, but found the explanation compelling enough to increase their acceptance. Further, since the MATE questions focus on “big picture” ideas, it may be easier for students to retain impressions of the correctness of the theory 6 months later while not being able to remember the more detailed nuances assessed by the KEE. The cause for an increase in the KEE score during the semester could be due to extrinsic motivation to learn evolution in order to get a better grade while their motivation for accepting is likely only intrinsic. Therefore, once the semester is over the facts pertaining to evolution are quickly forgotten while the attitudes remain intact because education that takes place by intrinsic motivation leads to sustained learning (Ryan and Deci 2000).
It may seem surprising that MATE scores increased beyond the end of the semester. This is most likely due to response bias. Only 30.8 and 23.3 % of the students that took the surveys during the winter 2013 and fall 2013 semesters, respectively, took the longitudinal surveys. While incentives were offered to students who took the longitudinal surveys (entrance into a drawing), those who actually completed it may have been those who had more interest in the topic. Interestingly, we found that students who initially had higher acceptance of evolution were more likely to participate in the longitudinal survey than those who initially had low acceptance of it (p < 0.01).
Another interesting finding is that students seemed to retain knowledge of the LDS stance on evolution while forgetting specific knowledge of evolution. There are some limitations to this specific finding. The knowledge of the LDS stance on evolution was measured on a scale ranging from “strongly disagree” to “strongly agree,” while knowledge of evolution was measured with a dichotomously scored test where they either got each question right or wrong. Since student responses on the knowledge they retained toward the LDS stance on evolution cannot be coded as right or wrong it is not possible to directly compare the retention of knowledge of the LDS stance on evolution with the retention of knowledge concerning evolution. However, we do find that knowledge of LDS doctrine remained while knowledge of evolution was lost.
Intriguingly, students who were not part of a discussion of LDS doctrine saw gains in knowledge of evolution that exceeded the treatment sections (Fig. 1c). A possible explanation for this is that students in the control section spent time learning biology content while their counterparts were discussion religion. These discussions took up to 75 min, which is 3.6 % of the total class time over the semester or 12.5–25 % of the class time devoted to the unit on evolution. Other variables that may have influenced this greater gain in knowledge could be random sampling, instructor effect, or learning style.
We recognize there are other limitations to this study. Foremost, we understand that our conclusions were reached from an exclusively LDS population of students. The LDS church is unique in the way its worldwide congregations are united by and adhered to the same doctrine. However, this is also a benefit in such studies since attempting this same study among other religions would prove more difficult due to the variation between congregations and sects. Thus, the LDS population serves as a homogeneous representative sample of highly religious people. Despite any limitations of this study, the results and principles we found are compelling and lead to meaningful conclusions that can be applied to the classroom and future research.