Should Evolution be Taught in Elementary School?

Science frequently challenges our intuitive understanding of the world. Even as an adult, I am constantly confronted with new scientific advancements and discoveries that don’t always line up with my preconceived notions. Such ideas are considered counterintuitive because they present themselves in ways that are counter to one's intuitive notions or “gut feelings.”

Counterintuitive concepts have been challenging how we understand the world for Geocentric (top) and heliocentric (bottom) models of the solar system ages. As early as the sixth century B.C., the idea that the sun, moon, stars, and visible planets all revolved around the Earth was commonplace. This idea is still shared widely by young children today. When asked to point to Earth when shown an image of the solar system, 69% of American first graders pointed to the sun. However, as students got older and more educated, they shift from this geocentric view (that Earth is the center of the solar system) to a more heliocentric one (that the sun is the center of the solar system).One of the most challenging and powerful counterintuitive concepts, the theory of evolution by natural selection, also happens to be one of the most rewarding; its ability to explain the complexity of life on Earth, and even (to a certain extent) human nature, is unprecedented. Despite its importance, however, evolution is often labeled as “controversial” and has not achieved widespread acceptance in the United States. Reports suggest that only 60% of Americans believe that “humans and other living things have evolved over time,” and even then only 32% of this group state that evolution is due to “natural processes such as natural selection.” Unwillingness to accept evolution has complex roots in religious and political identification, which I won’t go into here. What I will discuss is how recent cognitive research adds insights into our problem with widespread acceptance of evolution and suggestions on how to improve it.First, let’s admit that evolution is indeed counterintuitive. The idea that all life (from bananas to blue whales) is related and has resulted from billions of years of evolution beginning with single-celled ancestors is not exactly a superficial or simple idea—but it is correct. So how, then, can we improve an individual’s chances of coming to accept it?Recent studies lead by Deborah Kelemen strongly suggests that if you start presenting children with counterintuitive concept like evolution early, they develop a greater facility for applying analytical thinking when they are presented with something counterintuitive. This strategy may help prevent misconceptions about such concepts from becoming rooted in their minds.To begin to understand this conclusion, it is important to consider the biases present in how humans view the natural world. For example, regardless of their religious beliefs, adults, and especially children, are inclined to see design and purpose everywhere. Kelemen has documented this way of thinking, termed “promiscuous teleology,” in children as young as preschool, though it is worth noting that teleology—the idea that something exists for a purpose—is an inclination we all share. Children, however, are much more indiscriminate and casual in their application of teleology to the world than adults, ascribing purpose to all kinds of entities—objects, living and nonliving things, and their properties.Kelemen has found, for example, that when children were asked “Why are rocks pointy?” they responded with purposeful statements like “Rocks are jagged so animals can scratch themselves.” By elementary school (ages 6–10), kids begin to develop their own “folk biology” theories (that is, how people classify and reason about the organic world) about the world around them, giving explanations for biological facts in terms of intention and design. This can be seen in children’s design-driven descriptions for the purpose for a giraffe’s long neck—so it can reach the leaves at the top of the trees. This suggests that believing in creationism may be a very natural tendency, and that introducing evolutionary frameworks in childhood may help lay the groundwork for balancing promiscuous teleology with analytical thinking.To see whether young children could understand the mechanism of natural selection before the alternative intentional-design ideas had fully set in, Dr. Kelemen and colleagues presented five- to eight-year-olds with a ten-page picture book that illustrated an example of natural selection with a fictional population of animals called “pilosas.” In the book, the pilosas are described as insect-eating mammals, some with thick trunks and some with thin. The children are then told about a sudden shift in climate that drives all of the insects into narrow underground tunnels. Because of this, the thin-trunked pilosas were the only ones to be able to reach the insects, causing those with thick trunks to die off. Therefore, the next generation of pilosas all had thin trunks.Before they heard this story, the children were asked to explain why a different group of fictional animals had a particular trait. Most of them, consistent with previous research, gave explanations based on intentional design. However, after they heard the “pilosas” story, the answers they gave were very different. They began to understand the basic tenets of the theory of evolution by natural selection. Even three months later, their understanding and analytical explanations persisted.This study suggest that if we start teaching evolution sooner, with age-appropriate examples, we’ll be less likely to have students reaching high school with misconceptions firmly entrenched. Problem solved, right?Unfortunately, no. Additional research by Will Gervais suggests that differences in cognitive style may also get in the way of understanding and accepting evolution, suggesting that it’s easier for some people to accept counterintuitive ideas than others. It turns out that there is an association between cognitive style and beliefs about evolution. Cognitive style refers to the balance between two distinct mental systems that everyone uses for processing information: one system provides quick and effortless intuitive responses, whereas the other relies on more strenuous and analytical processing.

In an experiment with hundreds of Kentucky undergraduates, Gervais presented participants with a common task to measure the extent to which they would engage in immediate, intuitive judgments or more explicit, analytical deliberations (which can sometimes override the initial intuitive response). He found a significant relationship between the degree to which individuals would engage in more analytical styles of thinking and their endorsement of evolution. These results remained significant even after controlling for religious beliefs and political conservatism.Gervais’ research presents two possibilities: (1) The more an individual engages in reflective, analytical thinking, the more likely it is that they will essentially “override” their natural intuitive responses when presented with evidence, thus making concepts like evolution easier to grasp; or (2) Some individuals may naturally have stronger intuitive responses than others, which, though beneficial in some situations, may make it particularly challenging to successfully override their gut instincts. (Of course, for individuals who grow up in an environment where intelligent design and creationism are widely accepted, even those with a highly analytical cognitive style must override the norms of their community and upbringing to accept evolution.)This research helps to explain why counterintuitive concepts like evolution are not rejected only for ideological reasons, but also for cognitive ones. It also helps us understand the most recent Gallup poll results, which found that nearly half of the U.S. population rejects evolution, a result that has remained stable for the past thirty years. Kelemen and Gervais’ research suggests that to change that percentage, educators and parents must introduce evolutionary thinking to children when they are young, rather than waiting until high school, and that educators should be mindful that accepting counterintuitive ideas may be more difficult for some people than others. Keleman has shown that children as young as five can grasp these concepts (and retain the information); they just need to be taught through innovative ways like storytelling. Over the past few years some excellent evolutionary children’s books have been published, such as Great Adaptations, Grandmother Fish (see NCSE Stephanie Keep’s review and Q&A with the author here), and Our Family Tree to name a few. These can be excellent tools for teaching evolutionary concepts, second only to applying some imagination and having children create their own species and animals like Dr. Keleman’s “pilosas.” Reinforcing the concepts each year should help even those with more intuitive cognitive styles to grasp the basics of evolutionary theory.Counterintuitive concepts like evolution can be challenging for anyone to grasp. By taking a deeper look at the underlying cognitive hurdles, we can improve our future approaches to science education and policy, and do a better job helping students understand the elegant, if not at all obvious, theory that underlies all of biology.This article was adapted from an earlier version written for both NCSE (National Center for Science Education) and Learning & the Brain.