To see how science works, imagine you discovered two sets of dinosaur tracks. Also pretend that you are the first person ever to see these dinosaur tracks. You start with a simple question – which is the bigger dinosaur? You see that one type of footprint is bigger than the other (1). Your first hypothesis: “The dinosaur with the bigger footprint is bigger.”

But then you see that the footprints are farther apart for the dinosaur with little footprints (2). Your second hypothesis is, “Maybe the dinosaur with the small feet is taller because its footprints are farther apart.”

And then you notice that the big footprints are deeper than the little ones (3), and you think, “Maybe the big-footed dinosaur is bigger, because heavier animals should leave deeper footprints in the mud.”

You follow the tracks a bit farther, and find that the footprints of the big-footed dinosaur get farther apart (4) – and are even deeper, and you realize that he might be running after the small-footed dinosaur – which was running all along.

But do you know that for sure? How could you test whether your conclusion is right about which dinosaur is heavier?

Some answers given to me by third-graders in Cedar Falls, Iowa:

“You find dinosaur skeletons and see if the foot matches the footprints.”

“You see how the footprints change when the dinosaur is running (to do this, you have to run yourself – do just your toes touch the ground? Or your heels? Do your feet hit the ground harder?)”

But then, someone said, “The footprints are so old – maybe the two sets of tracks weren’t even made the same day!”

Fortunately, if you could match the footprints to dinosaur footbones, it might not matter whether the tracks were made on different days. In real life, you might also look at what dinosaur footprint experts have said about the two types of footprints you observed.

Have you heard of the “scientific method”? You have a question, you develop a hypothesis, and test it with careful experiments; and, based on these experiments, find out if your hypothesis is true…or something like that…

Scientists often write papers to make the “scientific method” look that way, but it’s usually messier. A typical scientific paper looks like this:
1. You ask the right question. The question is important. The answer will make the world a better place.

2. You find out what people already know, and it’s not enough. Then you can focus on what people don’t know.

3. You do experiments. Or take observations of nature. You do a better job because you know what others missed. You may know what others missed because other scientists wrote it down. Or maybe because you missed on your first try.

4. You look for patterns in your observations

5. You develop a hypothesis to explain the pattern, and it works.

6. You suggest a way to improve on your work.
In real life, scientists repeat Steps 3-5 until they find a hypothesis that fits the pattern. This might call for more data. For example, they might think of more than one hypothesis that explains the data, and they want to end up with only one. Scientists might have 40 different hypotheses or versions of hypotheses before they are satisfied.

Scientists might even go back to Step 2, because the new hypothesis (or data) might remind them of something they’d read earlier.

Or they might even go back to Step 1, because they might find out that they have discovered something that explains a lot more than the simple question they started with.

Next time, I’ll provide a specific example.