The Scientific Method
What do you think of when you hear about the scientific method? The decaying poster with a list of steps that's been on the wall of your science classroom since medieval times? A cookie-cutter lab that seems more like a chore list than an experiment? That band that played the Sunday afternoon show at Coachella? What if we told you that the scientific method isn't just for scientists? What if we told you that you've been using the scientific method basically since you were born? Mind blown yet? We're just getting started.
We've asked our fair share of scientific questions in our lifetime. "Why does my hair look like this when it rains?" "How does the internet work?" "What does a peanut butter and mayonnaise sandwich taste like?" We don't have to be a professional scientist to ask scientific questions. We just have to be curious.
So, how are scientific questions different than regular old questions ? First of all, they're testable. This means they can be answered with an experiment or by making measurements or observations. "Which smart phone has the biggest screen?" is a testable question. "Which smart phone is the prettiest?" is not so testable (go ahead and try to come up with a universally acceptable definition of "pretty").
Scientific questions also need to have real answers. If that answer involves a unicorn, a crime fighting ninja turtle, or a hippogriff, science can't really help us out. But if that answer involves something we can consistently observe or measure the effects of, we've got ourselves a scientific question.
A scientific question also needs to be able to be answered using natural processes and phenomena—basically stuff that we can observe and explain. "Which brand of sliced bread gets moldy in a locker the fastest?" is an example of a scientific question. "What color does the number nine smell like?" is not.
The scientific question has a pretty important job—it's what gives the whole scientific method a purpose. It's the reason why we're doing an experiment or researching to try and find an answer. If we didn't have a scientific question, we'd just be mixing chemicals and watching plants grow, and then all we'd end up with is a mess and severe boredom instead of knowledge.
A hypothesis has to be able to be tested. To make sure we're on the right track, our hypothesis should usually be in the form of an "if…then…" statement. For example, we hypothesize that if we eat an entire bag of Skittles, then our tongue will look like it has the Black Plague. Hypotheses can show up in other forms than an "if…then…" statement, but the gist of a hypothesis is that it's a prediction that can be tested. Our hypothesis can't simply be, "I like peanut butter." No matter how much we like peanut butter.
The other key characteristic of a hypothesis is that it's falsifiable. This just means that it has to be possible to be show that the hypothesis is false. Our Skittles example is totally falsifiable. All we need to do is down the bag of Skittles and produce a healthy-looking tongue to prove that hypothesis false.
On the other hand, if we were to suggest that there is a quidditch snitch hiding in a bag of Skittles somewhere, that would be unfalsifiable. To prove this statement wrong, we'd have to look for an absence of evidence, or no snitch. This makes it pretty difficult to convince someone that the snitch isn't simply hiding in a different bag of Skittles without looking at every single bag of Skittles ever made. We're getting a stomachache just thinking about it.
Having a falsifiable hypothesis keeps us moving forward in our scientific knowledge, because it allows us to weed out the ideas that simply aren't true. This is why scientists purposefully make their hypotheses falsifiable and then try to, well, falsify them. If an idea can withstand a bunch of skeptical scientists pulling out the big guns to prove it wrong, then it's that much closer to being right.
Now, even the greatest scientists will admit they've had a few wonky ideas that didn't quite pan out. And that's okay. If they had used an unfalsifiable hypothesis, they might have argued themselves in circles, thinking their crummy idea was right even when the evidence was screaming that it's wrong. Our Great Grandpappy Shmoop always said, "Tis better to be wrong and smarter, than wrong and think you're right."
Experiments tend to spew out a lot of data, which is really just a fancy word for information. How scientists collect these data, and what they do with them, really depends on the experiment and what they're trying to find out. Some data are all about the numbers, like if a scientist is looking at how many eggs a frog lays on Tuesdays. We call this quantitative data. Other data are all about categorizing the information, like trying to understand the sounds a frog makes after the sun goes down or the pattern of colors on its feet. We call this qualitative data.
Wait.
That questions thing sounds familiar. Wasn't that how this whole process got started?
You betcha. The scientific method is like the song that doesn't end, only infinitely less annoying. Every time a scientist does an experiment, they observe new stuff that makes them say "Huh?" again. And we know what happens when a scientist says "Huh?" They get their scientific method on and start working on ways to answer a whole new crop of questions.
Does this whole scientific method thing have your brain swimming in circles? Here's a summary of how it all goes down:
As an example, sometimes an experiment just isn't possible. Like what if we wanted to know what would happen if a giant asteroid hit Jupiter: what are we gonna do? Catch an asteroid that happens to be passing by, build a giant slingshot, and give it a heave-ho at Jupiter? Not in this lifetime. Instead of experiments, fields like astronomy rely on observations to make predictions, then scientists compare those predictions with new observations.
Sometimes the experiment itself can throw a monkey wrench into the exact thing we want to study. Let's say we want to learn more about the intense social politics in a gang of meerkats. Are those meerkats going to act like themselves with a human standing there asking them about their BFF? Nope. In this case, it's best to just sit back and collect observations to use as evidence.
Lastly, some experiments just aren't safe for the scientist or the test subjects. If a scientist wants to know if a shark's jaw is strong enough to crush a human skull, well, there are other ways to go about it than sticking his head in a shark's mouth. Or maybe there's a new parachute made out of recycled dental floss and gum wrappers that needs to be tested. Let's just say there won't be a human strapped to it on its maiden voyage down to Earth.
While the scientific method is an awesome guideline for doing science, it's just that—a guideline. We don't usually think of scientists as rebels, but they're out there, bending the rules and getting creative, all in the name of knowledge.
Scientists are constantly observing, asking questions, experimenting, observing again, asking more questions, designing more experiments…phew! So instead of thinking of the scientific method as a process with a single start and end point, think of it as a bunch of twisty-turny roads that are all connected to one another.
Francesco Redi lived in Italy in the 1600s, and he observed that maggots tended to appear in meat that had been left out. A popular explanation at the time was that the maggots "spontaneously generated", or basically appeared out of thin air. Redi, being the sciency scientist that he was, wasn't quite ready (see what we did there?) to accept that explanation.
So, he threw some meat in a jar and covered it with cheesecloth and threw some more meat in another jar and left it uncovered. Lo and behold, those sneaky maggots only appeared in the uncovered jar, which meant they weren't spontaneously generating, they were hatching out of eggs left behind by flies on the rotting meat. And thus, the science experiment was born.
Cue the Questions
Have you ever observed something that made you say, "Huh, how did that happen?" If not, you should really spend some more time on YouTube. If so, then you've taken the first step in the scientific method. Even the pros get started by making a simple observation. The exciting part is what comes after that observation: the scientific question.We've asked our fair share of scientific questions in our lifetime. "Why does my hair look like this when it rains?" "How does the internet work?" "What does a peanut butter and mayonnaise sandwich taste like?" We don't have to be a professional scientist to ask scientific questions. We just have to be curious.
So, how are scientific questions different than regular old questions ? First of all, they're testable. This means they can be answered with an experiment or by making measurements or observations. "Which smart phone has the biggest screen?" is a testable question. "Which smart phone is the prettiest?" is not so testable (go ahead and try to come up with a universally acceptable definition of "pretty").
Scientific questions also need to have real answers. If that answer involves a unicorn, a crime fighting ninja turtle, or a hippogriff, science can't really help us out. But if that answer involves something we can consistently observe or measure the effects of, we've got ourselves a scientific question.
A scientific question also needs to be able to be answered using natural processes and phenomena—basically stuff that we can observe and explain. "Which brand of sliced bread gets moldy in a locker the fastest?" is an example of a scientific question. "What color does the number nine smell like?" is not.
The scientific question has a pretty important job—it's what gives the whole scientific method a purpose. It's the reason why we're doing an experiment or researching to try and find an answer. If we didn't have a scientific question, we'd just be mixing chemicals and watching plants grow, and then all we'd end up with is a mess and severe boredom instead of knowledge.
The Hype About Hypotheses
Okay, so once we've made an observation that led to a question, it's time to come up with a hypothesis. A hypothesis is basically a testable statement about what we think is happening. We're not taking a stab in the dark here. Not only does that sound like a rather good way to lose a digit, it's not very scientific. Scientists like to do a little research and see what information is already out there to help them make the best hypothesis possible. After all, nobody likes to be wrong. Especially scientists.A hypothesis has to be able to be tested. To make sure we're on the right track, our hypothesis should usually be in the form of an "if…then…" statement. For example, we hypothesize that if we eat an entire bag of Skittles, then our tongue will look like it has the Black Plague. Hypotheses can show up in other forms than an "if…then…" statement, but the gist of a hypothesis is that it's a prediction that can be tested. Our hypothesis can't simply be, "I like peanut butter." No matter how much we like peanut butter.
The other key characteristic of a hypothesis is that it's falsifiable. This just means that it has to be possible to be show that the hypothesis is false. Our Skittles example is totally falsifiable. All we need to do is down the bag of Skittles and produce a healthy-looking tongue to prove that hypothesis false.
On the other hand, if we were to suggest that there is a quidditch snitch hiding in a bag of Skittles somewhere, that would be unfalsifiable. To prove this statement wrong, we'd have to look for an absence of evidence, or no snitch. This makes it pretty difficult to convince someone that the snitch isn't simply hiding in a different bag of Skittles without looking at every single bag of Skittles ever made. We're getting a stomachache just thinking about it.
Having a falsifiable hypothesis keeps us moving forward in our scientific knowledge, because it allows us to weed out the ideas that simply aren't true. This is why scientists purposefully make their hypotheses falsifiable and then try to, well, falsify them. If an idea can withstand a bunch of skeptical scientists pulling out the big guns to prove it wrong, then it's that much closer to being right.
Now, even the greatest scientists will admit they've had a few wonky ideas that didn't quite pan out. And that's okay. If they had used an unfalsifiable hypothesis, they might have argued themselves in circles, thinking their crummy idea was right even when the evidence was screaming that it's wrong. Our Great Grandpappy Shmoop always said, "Tis better to be wrong and smarter, than wrong and think you're right."
Experimenting: Everybody's Favorite Part of the Scientific Method
All righty, now that we've got the hypothesis out of the way, it's time to start the experiment. As we mentioned before, a hypothesis has to be testable and the experiment is how we test it. An experiment should be like a recipe—a list of ingredients and clear, easy-to-follow instructions on what to do with them. No one wants to start out making a cheesecake and end up with a turducken.Experiments tend to spew out a lot of data, which is really just a fancy word for information. How scientists collect these data, and what they do with them, really depends on the experiment and what they're trying to find out. Some data are all about the numbers, like if a scientist is looking at how many eggs a frog lays on Tuesdays. We call this quantitative data. Other data are all about categorizing the information, like trying to understand the sounds a frog makes after the sun goes down or the pattern of colors on its feet. We call this qualitative data.
Digging Through the Data
The next thing we need to do after we finish our experiment is analyze our data. Yes, those scraps of paper with numbers, observations, and some unidentifiable green stuff on them will need to be organized. Again, how we organize data depends on the kind of data we're organizing. Number stuff usually goes into a graph or data table, while physical observations might end up being organized into a diagram or flowchart, but it all depends on what makes the most sense for the experiment. When we analyze data, we're pretty much looking for patterns or trends that will give us evidence to either support or refute our hypothesis. That's what we're here for, right?The End. Or Is It?
Once our data have been organized and analyzed, it's time to draw conclusions. Yes, here we are, at the end of the scientific method. This is the moment of truth. Was our hypothesis right or wrong? What did we learn? What new questions do we have?Wait.
That questions thing sounds familiar. Wasn't that how this whole process got started?
You betcha. The scientific method is like the song that doesn't end, only infinitely less annoying. Every time a scientist does an experiment, they observe new stuff that makes them say "Huh?" again. And we know what happens when a scientist says "Huh?" They get their scientific method on and start working on ways to answer a whole new crop of questions.
Does this whole scientific method thing have your brain swimming in circles? Here's a summary of how it all goes down:
- A scientist observes a phenomenon.
- They ask a question about the phenomenon.
- They formulate a testable hypothesis to explain the phenomenon and answer their question.
- An experiment is conducted to test the hypothesis.
- More observations are made and evidence is collected during the experiment. These observations usually lead to more questions—head back to the beginning.
- The data from the experiment is analyzed for patterns and trends related to the hypothesis.
- Conclusions are drawn using evidence from the data to support or refute the hypothesis
- If the hypothesis is supported, continue conducting experiments to gather additional evidence and confirm results.
- If the hypothesis is refuted, use what we've learned and head back to the drawing board with a new hypothesis.
Complications
Before you go tattooing this on your arm for future reference, know that this is the basic gist of how scientists get stuff done, but it's not the only way to do things. Sometimes the steps are done out of order, or they might skip around a bit. One of the big steps that scientists often need to dance around is running an experiment.As an example, sometimes an experiment just isn't possible. Like what if we wanted to know what would happen if a giant asteroid hit Jupiter: what are we gonna do? Catch an asteroid that happens to be passing by, build a giant slingshot, and give it a heave-ho at Jupiter? Not in this lifetime. Instead of experiments, fields like astronomy rely on observations to make predictions, then scientists compare those predictions with new observations.
Sometimes the experiment itself can throw a monkey wrench into the exact thing we want to study. Let's say we want to learn more about the intense social politics in a gang of meerkats. Are those meerkats going to act like themselves with a human standing there asking them about their BFF? Nope. In this case, it's best to just sit back and collect observations to use as evidence.
Lastly, some experiments just aren't safe for the scientist or the test subjects. If a scientist wants to know if a shark's jaw is strong enough to crush a human skull, well, there are other ways to go about it than sticking his head in a shark's mouth. Or maybe there's a new parachute made out of recycled dental floss and gum wrappers that needs to be tested. Let's just say there won't be a human strapped to it on its maiden voyage down to Earth.
While the scientific method is an awesome guideline for doing science, it's just that—a guideline. We don't usually think of scientists as rebels, but they're out there, bending the rules and getting creative, all in the name of knowledge.
Common Mistakes
The biggest mistake we should avoid with the scientific method is thinking of it as a something that happens in a straight line. Yes, it's easier to think of the scientific method as a bunch of steps, and that's why we'll hear people talking about "the" scientific method like a DIY project. However, out in the science world, the scientific method is less like running the 100-meter dash and more like something out of Cirque du Soleil.Scientists are constantly observing, asking questions, experimenting, observing again, asking more questions, designing more experiments…phew! So instead of thinking of the scientific method as a process with a single start and end point, think of it as a bunch of twisty-turny roads that are all connected to one another.
Brain Snack
One of the first biology experiments ever (at least that someone decided to write down) was all about maggots in rotting meat. Yum.Francesco Redi lived in Italy in the 1600s, and he observed that maggots tended to appear in meat that had been left out. A popular explanation at the time was that the maggots "spontaneously generated", or basically appeared out of thin air. Redi, being the sciency scientist that he was, wasn't quite ready (see what we did there?) to accept that explanation.
So, he threw some meat in a jar and covered it with cheesecloth and threw some more meat in another jar and left it uncovered. Lo and behold, those sneaky maggots only appeared in the uncovered jar, which meant they weren't spontaneously generating, they were hatching out of eggs left behind by flies on the rotting meat. And thus, the science experiment was born.