What Killed the Dinos?: A Model for Exploring the Scientific Process with your Kids

My junior high daughter came home from camp and told me, with a sigh, “We talked a lot about the Flood again. I tried to tell my friends and counselors that the Bible wasn’t a science textbook and point out some facts about the world, but everyone just told me those weren’t really facts. They said science books are written by atheists who just see what they want to see based on their assumptions, and they can’t be trusted because they’re always changing their minds about what the facts are anyway. I didn’t know what to say to that.”

If you are an evolutionary creationist parent whose Christian fellowship tends to be in more conservative evangelical communities, you may have similar conversations with your children. They are in a unique position.  Unlike the average kid outside evangelical communities who feels free to take Ms. Frizzle’s word for it when it comes to dinosaurs or plate tectonics, my kids are frequently challenged by peers and role models for accepting what their well-loved books and PBS programs say is true. At times their confidence in the scientific consensus needs a boost.

Below is an activity for evolutionary creationist parents to use with their kids and address some of their unique concerns. It provides teachable moments to counter the common creationist contentions they may hear, such as:

• Scientists’ conclusions stem from the assumptions they bring to the evidence, not the evidence itself.
• Conclusions that don’t fit with what most scientists assume is true are automatically rejected.
• Scientific conclusions are just guesses that are constantly being replaced by new guesses.

This activity delves into an article from Science News For Students called “What Killed the Dinosaurs.”   As you read each section, pause to discuss the questions together. Following the questions are suggested student responses and tips for how to guide the conversation.

1) First, read the introduction to the article together

What claims does the article start with? Most of the world’s plant and animal species went extinct in a short period of time. The mass extinction was caused by an asteroid impact. The impact site is in the Yucatan Peninsula, Mexico. The asteroid impact caused mountains to form, triggered a tsunami, and launched debris into the sky that darkened and chilled the planet.

What do you think these claims are based on? Are they just creative guesses or are they facts? Do these claims seem based on assumptions? The article doesn’t go into evidence just yet, this is just to probe your child’s thinking on the topic.

What new hypothesis does the article introduce? Volcanic eruptions in India may have contributed to the mass extinction by destabilizing the Earth’s ecosystems. The asteroid impact may have triggered further volcanic activity.

How can you tell the difference between what scientists are presenting as established fact and what they are presenting as possibly true? What words are used? What do you think would have to happen before the ideas about the volcanic activity contributing to the extinction of the dinosaurs could be presented as an established fact? Discuss use of words like “some scientists,” “may,” “possible,” “could have,” “growing evidence,” “emerging evidence,” “conflicting evidence,” “clues,” “argue.” Probe your child’s knowledge about how a hypothesis becomes part of consensus science.

2) Read the section “The Smoking Gun”

What evidence led scientists to conclude that there was a massive extinction of many species about 66 million years ago? There is a clear boundary in the rocks all over the world between two periods, and fossils of three out of every four plant and animal species are not found in rock layers above the K-Pg boundary.

What hypotheses did scientists propose for the cause of the mass extinction before the asteroid hypothesis? Plagues, a supernova

What discovery in the 1980s pointed to a possible asteroid impact? A layer of the rare element iridium at the K-Pg boundary all around the world

What did scientists need to find to confirm their hypothesis about the asteroid impact? A crater from such a huge asteroid

Why do you think the plague and supernova hypotheses were rejected in favor of the asteroid hypothesis? Discuss how hypotheses are abandoned when corroborating evidence is not found and they don’t make accurate predictions about sources of new evidence.

3) Read the section “Inescapable Night”

What are scientists using to understand the effects of the asteroid impact? A new computer simulation

How do you think these kinds of simulations are created? Are they just created from the imagination of scientists? Do scientists know what the results of the simulations will be before they run them? Known information is programmed into the simulator, for example, levels of atmospheric carbon dioxide and estimates of soot levels. It is important to note that what is programmed into simulations are things that can be measured and act in predictable ways based on known rules of physics, chemistry, and math. Scientists aren’t just pulling something out of their imaginations and simulating what they want to see. They aren’t designing simulations ensured to have results that match their hypotheses.

What kind of information did the simulation reveal? Two years of darkness, falling temperatures in various regions

What observations did the simulation potentially explain? Why certain plants and animals may have been able to survive when others went extinct. You might want to point out that the scientific process is about finding explanations for observations, not finding observations that line up with an assumed explanation.

What corroborating evidence supports the hypothesis that the asteroid impact caused darkness? Fat molecules in the membranes of ancient microbes were modified by cooling seas and the fossilized remains of those fats provide a temperature record. You might want to emphasize that multiple lines of evidence leading to the same conclusion is one way to confirm a hypothesis and establish consensus.

4) Read the section “Buried Alive”

What predictable evidence did scientists find in the Hell Creek Formation that supported the hypothesis of a large tsunami caused by the asteroid impact? Sediment that contained iridium and glassy debris that formed from rock vaporized by the impact. Fossils of sea species such as snaillike ammonites were found washed up far from the seaway. Fish fossils had gills packed with glass. Here you can point out that good scientific hypotheses allow scientists to make predictions about new evidence they will find.

Does the hypothesis that volcanic activity contributed to mass extinction overturn the asteroid hypothesis? This would be a good time to discuss the creationist contention that science is always reversing itself, so its conclusions can’t be trusted. The volcano hypothesis offers an additional explanation and a refined understanding of the results of the asteroid impact. If it were accepted, it would not negate the established facts pointing to the asteroid impact, it would simply modify how we use those facts to explain the extinction.

5) Read the section “Death from Below”

How do scientists know the Deccan volcanoes were erupting before and after the asteroid impact? They can date the crystals embedded in the lava.

How can the scope of the Deccan volcanoes’ effects on the environment be traced? By measuring mercury levels in sediment and examining fossilized shells damaged by too much carbon dioxide in the atmosphere. Here you can point out that scientists confirm and reject hypotheses based on measuring things, not based on what fits their assumptions.

Besides mercury, what other effects of the volcanoes may have harmed the ecosystem? Carbon dioxide may have acidified the ocean and affected plankton, the base of the food web.

6) Read the section “Partners in Crime”

How can scientists know that the temperature changed around the time of the volcanoes and asteroid impact? By studying the chemical makeup of clam-like species’ shells over time; the makeup differs depending on the temperature at which they were formed.

What is something scientists disagree about when it comes to the reasons for the mass extinction? Whether the mass extinction was caused by the combination of the volcanoes and the asteroid or just the asteroid.

What counter evidence do the scientists who doubt the volcano hypothesis point to? Fossil evidence of sea life flourishing before the asteroid impact in many parts of the world.

Why are many scientists skeptical about the hypothesis that the asteroid impact contributed to increased volcanic activity? The physics isn’t firm and hard evidence is not there.

Why do scientists want to keep on studying the Deccan volcanoes and the Chicxulub impact site? To refine their hypotheses, be more certain about their conclusions, answer remaining questions, and disprove hypotheses that aren’t yet well-supported by evidence.

This article shows how the scientific community uses the scientific method to come to an agreement. Can you pick out some examples of the steps in the process? Scientists propose new hypotheses to explain observations, gather evidence to support their hypothesis, publish their studies, make predictions about possible new evidence and try to find it, and respond to the criticisms and questions of other scientists.

Your turn:

Some of us may feel inadequately prepared to walk our kids through science material, and we may even feel a little intimidated by the pushback we and our kids encounter in our communities of faith. But having constructive conversations about science and raising scientifically literate kids is something every parent can learn to do, no matter how many gaps we might have in our own science education. We can all ask questions like the ones in this activity and proactively address the concerns and suspicions about the scientific process that our kids will undoubtedly hear in their peer groups. It does not need to be something daunting. Why not try an approach like the one modeled above to discuss a news article or nature program about a topic that fascinates your child? Since the hallmark of scientific inquiry is bringing new questions and discoveries to the table, discussing science with our kids is a great chance to learn alongside them.