Young children are notorious for their surfeit of why questions, often directed at aspects of the biological world. Take a three-year-old to the zoo, for example, and you might be asked to explain why zebras have stripes, why elephants have trunks and why flamingos have such skinny legs. (Also: why you can't pet the lion, why another cookie is off limits and why it's really, really time to go home.)
Yet this childhood curiosity about the adaptive traits of biological organisms, which Rudyard Kipling recognized with his whimsical "Just So Stories," is all but ignored by current education standards in the United States. It isn't until high school — more than a decade after that curious preschooler wandered the zoo — that children start to learn how natural selection really works.
There are some good reasons to delay comprehensive evolution instruction. For one thing, an understanding of natural selection rests on concepts — such as deep time, randomness and probability — that are pretty hard to wrap an adult head around, let alone a child-sized head. In fact, even adults commonly have misconceptions about how natural selection works.
But in delaying evolution instruction, we may miss an opportunity to leverage children's natural curiosity about the biological world, and to establish the foundations for a more accurate scientific understanding before misconceptions become deeply entrenched. So here's the challenge for educators (and parents): figuring out how to teach evolution to children in a way that's compelling and effective.
It may be Kipling had it right. His explanations for how the leopard got his spots and how the camel got his hump won't win accolades for scientific accuracy, but they each tell a tale of biological change in a form we can all understand: a children's story. And in what might be a case of convergent (pedagogical?) evolution, two different groups — one of biologists and one of psychologists — have converged on the storybook as a medium for teaching evolution. These efforts show that scientists can create exciting, scientifically accurate materials for children, and — critically — that children can actually learn from them.
The first group just reached its initial goal of raising $25,000 on kickstarter.com for the creation of Great Adaptations, a children's book about evolution.
The book brings together evolutionary biologist and children's book author Tiffany Taylor, Robert Kadar, founder of the online magazine This View of Life, David S. Wilson, a well-known evolutionary biologist, and a team of scientists and artists who will work together to create stories illuminating subjects such as crow intelligence, cooperation and photosynthesis.
Tiffany Taylor corresponded with me by email about the book, which she describes as "true 'just so stories' with a solid biological foundation." She highlighted the project's complementary aims of fostering genuine scientific curiosity alongside teaching basic evolutionary thinking:
My hope is that [the book] will equip children with the right tools to view the living world from an evolutionary perspective. By understanding how adaptations benefit an organism in a given environment, it will hopefully allow them to look at any living thing and make a good guess as to why it might look or behave the way it does. The first step to becoming a scientist is to be curious about the world, and we hope this book will inspire and encourage curious minds.
The book, which targets 8- to 12-year-olds but is designed to appeal to a broad range of ages, is expected to be ready in October.
Of course, it's one thing to provide children with beautiful, scientifically informed material. It's another thing to have them actually learn from it. That's where a group of psychologists comes in with the timely publication of a paper demonstrating that evolutionary understanding in 5- to 8-year-olds can be improved by — that's right — a storybook.
The paper by Deborah Kelemen and colleagues, just published in the journal Psychological Science, reports studies in which children worked through a 10-page storybook about fictional "pilosas" and how they changed from having highly variable trunk widths to predominantly thin trunks today.
In an email conversation, Kelemen explained some of the background to the studies as follows:
There have been a slew of education studies over the past 30 years indicating that adults don't tend to understand adaptation even after instruction. This is often because they maintain inaccurate teleological ideas that natural selection transforms animals to give them the body parts they need or animals transform themselves through their own efforts.
These kinds of misconceptions, which focus on change within individuals, are extremely effective at shutting down an ability to accurately see natural selection as a population-based process.
In other words, people tend to think of evolution as a goal-directed process that changes individual organisms rather than a selective process that changes the makeup of a population of organisms over successive generations. To illustrate this crucial difference (and to test your own scientific literacy for good measure!), consider this question from an assessment of evolutionary understanding developed by psychologist Andrew Shtulman:
A youth basketball team scores more points per game this season than they did the previous season. Which explanation for this change is most analogous to Darwin's explanation for the adaptation of species?
(a) Each returning team member grew taller over the summer.
(b) Any athlete who participates in a sport for more than one season will improve at that sport.
(c) More people tried out for the same number of spots this year.
(d) On average, each team member practiced harder this season.
The correct answer is the third. But the others may be compelling because they exemplify plausible — but inaccurate — mechanisms by which biological adaptations could arise: by a process analogous to growth (option a), to a change in strength or force (option b), or to intentional action (option d), the process that figures in many of Kipling's "just so" stories.
Using measures more appropriate for young kids, Kelemen and colleagues assessed their participants' understanding of the "population-based logic" of natural selection both before and after reading their storybook. For example, kids were shown an image depicting "Wilkies," and were asked to explain how grown-up Wilkies went from mostly having short legs many hundreds of years ago to having longer legs today.
The results were encouraging. In one study, only 11 percent of 5- and 6-year-old children met the minimum criterion for population-based understanding before reading the story. But 54 percent did so immediately after, and 43 percent continued to do so three full months later. For children aged 7 and 8, the learning gains were also significant, jumping from 42 percent before the story to 90 percent after.
Kelemen credits the intervention's success in part to its storybook form, including the use of narrative and drama:
Narrative is a great way to offer a very extensive explanation–it ties together a lot of different ideas into a cohesive theoretical unit.
The picture book format is [also] wonderful because kids are intrinsically motivated. Even though the storybook itself is pretty stripped down—no bells and whistles even in the pictures—there's a lot of drama. The story is about life and death. Kids want to know what is going to happen next.
Naturally, Kelemen is enthusiastic about the potential implications for science education:
Children learned a lot from one pretty basic storybook intervention so imagine what a curriculum spread over several years might do for scientific literacy long term. It's an exciting thought.
Given the poor track record for most educational interventions targeting evolution, a short (and pleasant!) activity that actually works is exciting for both educators and science-minded parents.
Understanding the basics of natural selection isn't just important for appreciating contemporary issues like antibiotic resistance and answering your three-year-old's questions at the zoo. It's also a thrilling scientific theory at the core of contemporary biology. To quote Great Adaptations' Tiffany Taylor:
Evolution is a foundation of biology, not an optional extra.
You can keep up with more of what Tania Lombrozo is thinking on Twitter: @TaniaLombrozo
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