Biology 1010 Lecture 2 The Scientific Method

– Now, before we start learning about atoms and how atoms come together to form molecules, and the like, we first have to look at how we approach the discovery of any endeavor, not just biology, but anything because what you’re gonna see throughout the semester is, there’s a lot of things we know, very well There’s a lot of things we know, fairly well And there’s a whole lot of things we kind of know about And the problem is our method of investigation, sometimes, we just cannot learn all of the answers, we either don’t have the technology for it We haven’t studied it enough And so this lecture is all about how we go about learning new information, and it doesn’t just apply, like I said, to biology in fact, a good number of your questions are gonna have nothing to do with biology They’re gonna talk about problem solving your car, forking out $500 for a stupid alternator, like I am right now Whether you’re a mechanic, and you get paid really well to problem solve, whether you’re a computer designer or program designer, and you’re figuring out issues and all that, the same methodology applies So this is gonna be important because we’re not only gonna learn why and how we gain information, but you’re gonna see why we make so many mistakes today too So you can see that, yes, we’re not trying to trick everybody by saying, “Oh, shoot, we got this wrong.” It’s just the methodology is not always perfect and the way we executed is not always perfect, because it’s very difficult to do So that’s the goal of this lecture, is to see what the scientific method is, how it applies, and very specifically, what is our level of acceptance of the various concepts that we’re going to learn from hypothesis through law All right. So let’s start with the first thing, the scientific method, is not as simple as we usually portray it, we’re gonna put it forward simply today, but, and in a way of four steps, and you go through those four steps, it’s not as simple as that But we’re going to study it in this simplified version Because the real thing is, as you go through these steps, you’re always hitting hurdles You’ve gotta discover new technology, some new protocol, and you get stuck in various parts and have to go round and round around until you can, plow through to the next level And that’s why it takes so many freaking years to your graduate work and all that stuff The scientific method is essentially a way of gathering information It’s a framework of repeatable experimentation That’s how mechanics are able to deduce, this is how things should work, this is out of place, this is the issue, at least good mechanics can And as far as scientists go, they’re trying to observe what’s going on and understand the natural laws that are in our universe But this can apply to any type of endeavor, not just science, not just cars, not just computers, but any endeavor We’re trying to understand how everything works, that’s really what it’s all about So, this shows more of a cyclical nature of the scientific method because it never ends, ever Until we know everything, that’s not gonna happen anytime soon So the reason why it’s cyclical is because we build upon our prior knowledge We’re constantly making greater and greater discoveries, based upon what we’ve learned in the past And that’s one of the important aspects, as you can see here to make known what we discover so that others can work off of our shoulders, so to speak, and we can make greater and greater advancements If we lose that knowledge And you have a society that’s completely isolated from that then they have to start all over again or start from scratch I mean, that knowledge has to be passed on, otherwise, it’s lost So there are four main steps I know there’s several things in here, but there’s four main steps that you’re gonna be tested on They’re representative of again, how your multiple choice questions are gonna be And they’re as follows, observation, hypothesis, experiment, and conclusion So those are the four basic steps of the scientific method So let’s start with number one, observation A lot of times people just kind of miss this one as an actual step of the scientific method but let me give you some background history as far as why that’s so important Until scientists had actually been able to,

create microscopes and see the very, very small, we couldn’t come up with cell theory, we didn’t understand that living things were made of cells, we couldn’t see that small, the resolution of our eyes is just not that good So until we had the technology to start observing, the very, very small, we didn’t understand some of the fundamentals of life Let’s go broader Let’s go out into the universe, scientists are constantly trying to figure out how our universe works and whatnot, they’ve got massive telescopes and satellites and other things They’ve discovered, they’ve known this for quite a while, but it’s fairly well accepted among scientists is that, about 96% of our universe is unobservable by us, this constitutes two main substances which we call dark matter and dark energy That means, when you look out in the night sky, you see all those stars and you know that there’s other things and nebulas and other things out there that’s 4% of our universe So there’s quite a bit that we have yet to learn because 96% of it is unobservable How do we know that that even exists? We’re only now beginning to see the influence that this matter has on the 4% of observable matter but we cannot directly observe this yet So there’s a substantial amount of observation yet to come about once we start figuring out how to make those observations of what our universe is really made of It’d be like living in the ocean, and knowing what the individual salt particles are, but not knowing what water is I mean, that’s how ridiculous it is Observation is the very first step You need to be able to observe something if your going to learn about it So without the necessary tools or instrumentation, I mean, we have radio waves going through us all the time, we have all sorts of electromagnetic energy passing through And without the proper tools, we’re completely unaware of it You just can’t detect radio waves unless you have something that can pick that signal up and interpret it All right. So once we make an observation, the natural tendency is to ask, what is it that we’re observing? But that’s not an actual step of the scientific method That’s just a, hey, what is that? What’s that dark matter? What is that cell or whatnot? The second stage of the scientific method is to formulate what we call a hypothesis A hypothesis is your educated guess and we stress educated, but it’s a guess, nonetheless, of what it is you’re observing So you see something and you’re like, “Hey, I think it’s this.” The more knowledge you have about a particular phenomena, fixing the car, computer programming, the more knowledge you have, the better your hypothesis For example, let’s look at a car You wake up as I did six o’clock this morning, you go out to your car, try to start it and it doesn’t start, as always There’s a number of reasons on why a car won’t start Your observation is the car won’t start Your hypothesis is, what is wrong? What ultimately is making it so that the car will not start So let’s come up with some viable hypothesis Lemme throw a really bad one out there The tires are flat Would that be a good hypothesis? Why not? – ‘Cause it has nothing to do– – ‘Cause it has nothing to do with whether the car will start What if I’m from the 18th century or 17th century whatnot? I don’t have any prior knowledge on what what matters in the car But today, most of us have a good understanding at least, of some of the basic mechanics of a car But that’s where, a good mechanic can get right to the problem, a bad mechanic or a dishonest one muddles around and doesn’t quite get to the actual reason So let’s look at some viable hypotheses, on why the car won’t start – The battery – Okay, battery’s dead What else? – Your alternator died – My alternator is not working – Starter – Actually it fried my car, instead of not being able to Starter, so you’re dealing with things like the solenoid and other instruments What is another easy reason? – Gas – Gas, okay, out of gas Being cold, we usually know that

that tends to have an effect on batteries, especially when they sit there for long periods of time So, let’s just choose this one There’s many we can choose from And there’s actually little warning signs when you try to start up the car that the more you know, you can even do a diagnostic in the moment that you’re trying to figure out what’s going on It’s not necessarily an experiment But again, the more knowledge you have, the more you can be like, “Well, the car doesn’t even turn over, “so it’s very likely the battery.” But if the car is turning over, then you’re dealing with maybe some other issue or whatnot So, the more you know about it, the more you can get to the answer right away So let’s deal with an experiment Let’s say that the battery is dead What are some good approaches to testing your hypothesis and here’s the other aspect about a hypothesis It must be testable There are many hypotheses out there that people have regarding various observable phenomena, and a good majority of them can’t even be tested So they’re not good hypotheses because, a good hypotheses has even the capacity of being tested, theoretically or otherwise Sometime experimentally, where we actually perform something but there’s a lot of theoretical physicists out there that are able to say, theoretically this is possible and so that just leads us in the right direction or whatnot So experiment wise, what can you do? – Replace the battery – What’s that? – Replace the battery, – Okay, you can replace it – Try and jumpstart it – You can try to jumpstart it Those are two, anything else you can do? – You can test other things and if they’re not bad then, process of elimination – Okay, so if you have the instrumentation you can, weed out some of the other factors to try to get it all the way down to one I don’t know how I write that up there, but won’t do that – The way it sounds – Okay, so as you start it, the sounds that it makes Okay, so obviously, most of us don’t have the knowledge that a mechanic has, and we usually go with the simplest solution What do we usually do when the battery’s dead? What’s the most obvious thing? Before even try to jumpstart it, because we don’t wanna pay the money to replace a battery if we’re not sure that that’s what it is We just wanna say, “Hey, maybe it’s just so cold outside.” That, “It’s just ran out of energy, “and we just need to give it a jumpstart “and it’ll work.” As long as the alternator works Let’s go through the experiment process You have to make sure this is where things start getting, where you’re gonna understand why scientist make so many mistakes Why we have drugs that get out there that are recalled Why we keep revising the things, is because you really can’t set up the most perfect experiment but you can get close, the better you set up your experiment, the better your ultimate knowledge comes into play The worse you do your experiment, the worse things tend to be So there are a number of ways in which you can do this experiment For example, make sure that the cables are set up properly or you’re gonna get a nice little jolt How long do you let it go for? Do you let it go for a minute? No, you gotta let it go for longer, experience shows that it takes maybe even 10 minutes Now there are other things that can apply a larger voltage if you’re not doing it car to car There’s many ways to do this But there are right and wrong ways If you do it too little, you haven’t performed the experiment properly to test your hypothesis that the battery is dead So we’re gonna spend some time a little bit later on today, looking at how to set up an experiment well, so that you can reliably say, “Yeah, I did a good enough job “that these results are good.” So we set up our experiment, we jumpstart the car, let’s say we do it right as you’re supposed to jumpstart the car and then at the end, we turn the ignition, the car starts up This is a part that people tend to get confused on, especially when it comes to testing aspects So I’m gonna make it really simple for you The starting up of the car, the eureka moment where you’re like, “Yay, I can go to my class and,” well, maybe not a eureka moment But yeah, I get to go to my class, and whatnot All of that’s part of the experiment The conclusion, only has one statement to it There’s actually two possible statements but it’s one or the other You either support your hypothesis,

or you reject your hypothesis, that’s the conclusion It’s not the crunching of your numbers, it’s not even the analysis of your data, it’s not any aspects That’s all part of the experiment So usually, when in doubt, most of the time you spend, be it in your PhD or other things like that is in this part right here And then you write, a 200 page, long paper and one sentence at the end, which is your conclusion that you were right, or you were wrong Usually, you have to be right to move on So, it’s not the analysis of your data It’s not, hey, the car started up That’s not the conclusion It’s, was I right? Was it the battery? Yes So, we support our hypothesis Let’s say you go through this process, and the car still doesn’t start up And you you tested everything you could about the battery, then what would you do? Would you support your hypothesis? No, you reject it, because you’re like, “Well, I tested it, it’s not the battery.” Now what do you have to do? You go back, and you take up a new hypothesis So if the battery is not dead, what’s another likely problem? – Alternator? – Alternator, yeah Yeah, that could be another aspect of it I usually choose the gas but my kids are not old enough to drive yet But when they do, I know they’re gonna leave it out of gas all the time The main point of this is, when you’re thoroughly convinced and you reject your hypothesis, you go back and do a new hypothesis You don’t go back to here and start messing around with the data until you support it That’s when you start getting into trouble That’s when you get certain dishonesty in pharmaceutical companies, where they just kind of skip certain steps, skip certain data and push something through I’m not saying all pharmacies are dishonest, just saying that dishonesty is out there So in some situations, people don’t do what they should do, which is go back to the drawing board, because this going back to here, could mean millions of dollars That’s understandable why sometimes, people don’t wanna do that To make things a little easier for others, as we gain this data, we publish it because we need to work on the shoulders of others, like I said But that doesn’t mean that, everything that comes out in these journals is absolutely correct There have been really bad PR things where people have come out with things that have been published in really vetted journals, and they’ve been shown to be a farce or faults or whatnot And the reason why it’s so bad is because it puts a bad light on the other scientists that are honestly being honest and trying to do well So yes, there are situations where scientists will fabricate and lie But my experience shows that most do the best that they can Yes, you’ve got always some bad apples in every type of endeavor you do This is more of my soapbox, but you’re not gonna be tested on this But, this is really an important aspect Maybe one of these days I will test on it But one of the biggest pet peeves that I have is that the media, also the media, but the media and other sources of information will take what scientists publish and say, and use that for their own agenda They’ll say, “Hey, this is what the science says “so therefore, we must do this.” And the problem is they’re implying that, because of certain results, that we have to do these things, and the reality is science is impartial Science is just about gaining knowledge, it doesn’t tell us what we should do with that knowledge, nor how we should use it So we have to make ethical and moral judgments all the time, about what and how to do with the new knowledge and new information we’re getting But it pisses me off to no end when, I’m not just saying politicians, but anybody uses the data to say, “They’re meant to do this.” It’s not they should be separate issues It should be, “Hey, this is what’s happening.” We as a society, what should we do about it? And I think that’s the biggest problem is, most people will reject the science because they reject the judgments of how we should use that science

And that’s a big thing that we’re dealing with today And I blame the media for that But, sometimes we as scientists don’t get our point across as well We tend to want certain things, we’re human, we want this progress to be made and other things like that So, just be aware that there are many out there that the reason why people, usually, reject certain scientific theories is because of what people are saying we should do, or what you should understand this to be, based upon that theory And hopefully, as we go through here, you’ll see that once you understand the science of it, it’s just about knowledge It’s about learning how things really are Okay, now with that This is on your quiz So it’s important that we understand these aspects As we go through the scientific method, there is a certain level of confidence that we have in our knowledge Hypothesis is merely an educated guess, it has zero supporting data to it As such, it is the weakest of any concept because anybody can make up a hypothesis, anybody can come up with a reason, a guess So, when we look at the progression of the scientific method it has to start somewhere We observe something, we’ve gotta at least try to reason it out and that’s where hypothesis begins If you go through one round of the scientific method, it doesn’t immediately become a theory It has to go through, sometimes, thousands of vetted experiments before the general scientific community accepts it as a valid hypothesis At that point, then we call it a theory The main difference between theory and a hypothesis is, a theory is a more thoroughly tested and accepted hypothesis That’s really what a theory is Which is also why when I watch shows, it pisses me off when people use the word wrong They come upon some scenario, they see, dead guy, they’re like, “Hmm, well, here’s my theory.” No, it’s your hypothesis is what he has, not a theory till we test that Theory is essentially a well accepted hypothesis, the scientific community or the community in that discipline, pretty much says, yeah, this is how it is This doesn’t mean, one, that we know everything about it, but it is the best explanation that we have amongst all possible explanations And so when Reagan and others say, “Oh, it’s just a theory.” That really hurts right here, you know, because it’s not just a hypothesis If you said “Oh, that’s just a hypothesis.” Then yeah, have that but it’s not just the theory And so there are several theories For example, cell theory does a good job of explaining what life is because as of yet today, we have not seen anything that exhibits the characteristics of life that is not made of cells Remember, there is still debate about viruses and whatnot So again, that’s where theories come into play Most scientists accept cell theory as the theory that all living things are made of cells But there are some that still reject that and say, “Nope, viruses are alive “They exhibit all the characteristics “that we consider life.” And there’s good healthy debate We’re not choking each other out and trying to pore each other whatnot We’re just trying to learn what life is Now, Principles. Principles are more concrete concepts, but they don’t explain the broad subject What do I mean by that? For example, we have the theory of evolution It describes many things, and it reasonably shows how things progress However, within that theory, there are some more concrete concepts, which we call principles In fact, within the theory of evolution, there are five principles Everybody knows about one of them, natural selection, but there are other principles that govern evolution, such as mutation, and gene flow, and genetic drift Don’t worry about writing all those down And sexual selection and whatnot These are principles of evolution So a principle is more narrow in it’s scope and what it defines It’s not as broad as a theory You can almost equate principles with facts But we understand it better

So in that endeavor to understand how a theory works, how the mechanics of evolution work for understanding the dynamics, there’s many theories we’re gonna go through this semester We usually incorporate what we call principles, which are very well defined concepts, very well defined facts within that theory Now in the end, this is what we’re after We want to know how everything absolutely works And this is where law comes into play There’s many laws that we have in science, we have laws of what we call thermodynamics, where we understand how chemicals and molecules interact with one another We have the law of gravity, where we understand how gravity works so well, that we can predict I throw this pen at a certain distance at an angle whatnot, I know exactly where it’s going to fall So the more we understand the concept, the more we can predict what the outcome is going to be That’s really what our endeavor is in the scientific method is to understand how everything works even in biology, we have laws They’re called the laws of inheritance We understand how biological inheritance work so well, that we can make calculated predictions about the outcome That you have these two individuals, they have a 25% chance of having a child with cystic fibrosis Those are the laws of inheritance And we’ll learn that later on in lecture 15 or so So, as we go through, you’re going to see these concepts over and over and over, cell theory, theory of evolution, Bayless electron shell theory, that’s next lecture and whatnot Then we’ve got natural selection as a principle, we’ve got the Heisenberg uncertainty principle which is part of the valence electron shell theory That’s next lecture, whatnot We’ve got theories of our laws of gravity, thermodynamics, entropy, I told you about entropy, that’s a law, that’s a pervading law through the entire universe on how energy is transferred and the like So that’s really the goal of the scientific method to understand everything, and this is the progression Now, for the last part of this, let’s look at experiments We’re gonna talk about drug trials We’re gonna talk about, a number of different things that come up today Why did I get the H3N2 virus? Why did people who got the flu shot get that virus as well? We’ll show why we make mistakes in creating vaccinations, and doing drug trials and discovery and whatnot, because it is so difficult to work with as dynamic a system as is the human body It’s much simpler to work on a car, or to work on some other aspect to figure out what’s going on, the mechanics of a car is much easier than the mechanics of a living being When we do these experiments, there are many, many things that we have to control for, most of the time, we can’t control for them all One of the biggest things that we have to deal with first, is sample size There are billions of people on the planet But when you’re creating a drug, you can’t test it and every single person So you have to take a sample size, a representative group, and this is where we get into problems because, if you’re not representing every ethnic group, or genetic diversity on the planet, if you’re not taking samples from people all over then your sample size only represents a small portion of the general populace as a whole This is why when drugs get vetted, and they go through, they’re expecting that there are certain parameters they didn’t test for, with people with certain genetic diversity, in India, or in Africa, or in some other area where we might not have sampled from and tested the drug in our human trials So in that scenario, the more representative sample you can get, the better your data’s going to be You cannot extrapolate and say, “Oh, I took someone from every continent except for Asia.” That’s where most of the people on the planet live So, you need to have a representative sample When you get that representative sample that you’re doing your experiment on, be it a drug trial, whatever the case may be, there are the variables and this is where things become so difficult because in any scientific endeavor,

the only way to look at cause and effect, I give you a drug, I wanna see what happens as a result The only way to look at repeatable cause and effect is to make sure that there is only one variable that you’re accounting for, everything else get standardized, so to speak So let’s look at the different variables that have to be factored in The independent variables is what you manipulate Lemme give you some examples Let’s say we create a vaccination and we want to determine how much of the vaccine we want to give to allow the children or whatever group, whether it’s adults for the flu virus, or whatever the case may be We wanna test, how much of it we need to give for it to be effective or so effective That’s the independent variables It’s what you manipulate within these independent variables, we have what’s called the placebo effect, which is a big problem, especially in humans, we have to do this, because due to the complex nature of our physiology, the mere thought that we’re taking something that will cure us, causes a chemical release, causes a physiological change that can actually get us better So we think we get better, it’s the positive attitude, or whatever the case may be, we think we’re getting some drug and we do and they shown that if they’ve got a group of individuals that take nothing whatsoever, and they give another group, just some sugar pill, they’d say, “Hey, this is gonna cure your migraine.” There is a significant difference They didn’t give ’em anything but just a little bit of sugar, but they didn’t know that And so when we look at drug trials, we have to see something above and beyond the placebo effect Because if you’re looking at something like this, your drug is crap It’s no different than the placebo effect So that’s why we have to do that Another thing that has to be done when we’re doing placebo controls is what we call a double blind, where the person giving it, doesn’t even know which drug it is, and why would we have to do that? Those are variables that have to be accounted for Because, if you’re doing something of this nature, and all of a sudden, you see something like this, then somebody probably leaked what the placebo, which one’s the placebo, which one’s not, and people are like, “Well, I’m not getting the placebo, type of thing.” So it can really mess up your results by not accounting for all of these variables That’s why when we do placebos, neither the person giving nor the person receiving knows, which one’s the right drug and which one’s just an inert substance like, sugar, salt or whatever the case may be, all right So a placebo or the actual vaccine, these are what we call the independent variables, what you manipulate In this situation, you’re not changing the vaccine, you’re just changing the amount So those are the controls, the manipulated variables The second type of variables are, what’s the outcome? Do we call these the dependent variables? Because they depend upon what you manipulate, or the independent variables? So the dependent variables is, what’s the outcome? What’s the results of that? So they showed that, when they gave children this placebo, it wasn’t actually a virus, it was administered the same way whatnot But there was no virus then about 15% of them got sick, when they gave a low dose, a little less, and they’re like, “Oh, this is the minimum “we need to give at this point “to be able to have the virus be effective.” So that’s that was their conclusion but, there are so many other things that go into it to make sure that you get accurate results Let’s look at some examples This is where the third set of variables comes in This is the most difficult part of any experiment We call them standardized variables So what are standardized variables? Basically, all other factors need to be held constant, so that only the independent variables and the dependent variables become correlated Lemme give you some examples Let’s say for some reason that in this group, you just couldn’t find 80 children So they ended up just having like 10 and the others they had 86, 78 and 87 That would not be keeping everything standard, because you would end up getting a different set of statistics with just 10 children than you would with 80 So they try to keep these numbers as close as possible Ideally, they would be all the same

How do you administer it? Do you inject some children with the needle and others give a droplet? That’s gonna change your outcome So you need to make sure you administer it I mean, you poke a child with a needle, you’re gonna cause a physiological reaction that might mess something up I mean, we’re very dynamic creatures So if you give one group, a dropper with a vaccine, you better do it to all and so on and so forth If you give ’em five drops, give five drops to all and all of that Keeping everything standard, that’s probably the most difficult thing to do Because you gotta also have the representation If you have 80 children, but they’re from one ethnic group and 80 from a different ethnic group That’s not good You’re not keeping things standard, you need to make sure that all are represented in that group Otherwise, you get too many variables to account for Because it could be that this ethnic group just has an innate immunity to that virus, that you didn’t account for And you’re like, “Oh, this is the minimum,” and then you try it out there, and people are getting sick So that’s where problems come into play All right. Let’s do some more examples Let’s say you’re doing some farming Scientists wanna know whether or not they should add fertilizer to their crops Plants don’t have the same physiology as you and I, they don’t understand that they’re getting fertilizer versus not fertilizer, but you still have to do a placebo like effect, you’re like, “Why do we need to do a placebo effect?” Lemme show you Let’s say that you have these crops in the dirt And in this one where you’re not gonna add any fertilizer This is your control This is your placebo or whatnot And over here, let’s say you add a pound of fertilizer, and here, two pounds of fertilizer adding that extra pound or two might be the main reason, it might not be your fertilizer, it may just be the fact that you’ve added more weight to the soil and other things So one of the biggest issues you have to deal with is, if you add a pound of fertilizer, you better add a pound of something inert, that’s in the soil to compensate so that they’re in the same amount of soil, maybe the roots don’t have as much space as these roots to grow, and these absorb your nutrients Again, you’re standardizing the variables between all of these So even though you control for the amount that you give, and those are your independent variables, how much fertilizer you give, you need to be making sure that, everything else remains constant, the volume of dirt that these are in and so on and so forth In the end, obviously, these are the dependent variables, how was the yield? How many tomatoes did you get per bind, and as a result, you can make some conclusions The sample size wasn’t great They did three plants, it could have been much more So it’s not that great of an experiment, when you’re only doing such a small number, it doesn’t represent the whole Let’s do one more, lemme show you one more Here’s another experiment All of these are potential experiments on your quiz Some of you might get one where it describes this plant, they’re very simple They’re very straightforward And the only thing that you’re really gonna be tested on is, I’ll describe this process and say, “Oh, when they gave no fertilizer, “low fertilizer or high fertilizer, “what type of variable was this?” That’s the independent variable Or when they looked at the yield of the tomatoes, what type of variable was that? It’s a dependent variable and the like Let’s do one more Scientists have a question They think that they have a hypothesis that people will get ulcers, primarily due to a particular strain of bacteria that’s in their gut So they wanna test this hypothesis in order to test this hypothesis, they’re manipulated or independent variables is they use a couple of different antibiotics, because they want to see which antibiotics might kill that strain of bacteria better And then ultimately, what the outcome is, as far as ulcers go The dependent variables is, do the ulcers, that the people get decrease as a result of the treatment? So obviously, you’re gonna have your placebo group that gets an inert substance It’s not an antibiotic at all, but it’s inert And you find that 10% of them actually, have reduced ulcers just by taking a placebo And then you look at antibiotic A and antibiotic B, and you see your respective results of how many people got better from the ulcers The hardest part here again is, the standardized variables Here you’ve got a mix of people up there,

of different races, different ages, men and women, hopefully, you know we’re very different from one another So it would not be a good idea to put all the women in one group, all the men in another group And there’s nothing left for the third group But if you have, men and women in the third group and men represented that way, it’s not standardized, because there’s gonna be substantial differences in our overall physiology So each group needs to be represented Ideally, you would have groups of triplets The only triplets I know are from my sisters, she does have triplets, I’ll get on more of that later But identical triplets, because all of their genetics are pretty much the same, and they’re all the same sex and so on and so forth But we really can’t do that So we do the best that we can by reducing any variation between ethnic groups, between age, between male and female physiology and the like That’s really what standardized variables is all about Making sure that, if there are differences, that they are representative in each of the groups, so that in the end, we manipulate a variable, and we see some outcome And we can draw a direct correlation between those two There’s no other confounding factors Think about the car scenario, again, if you were to have a hypothesis that the battery was dead, but you’re like, “I just don’t have time “to just test the battery, “I’ve gotta test another hypothesis.” You fill up the gas, and you jumpstart the battery while you’re filling up the gas And then you start the car, you’re like, “Yay, it was both.” No, because you didn’t account for one variable at a time, you were looking at two different things, you wouldn’t be able to know which one it was The same thing is true And that’s why you effectively look at one variable at a time, otherwise, you just don’t know which variable it was All right. Now we’ve got about five more minutes here, I’m gonna let you dissect down this Calvin and Hobbes and come up with the fundamental scientific method, the observation, the hypothesis, the experiment and the conclusion Then we’re gonna spend a little bit of time, talking about what he did right or wrong with his experiment from sample size to, the overline, design of it and all that kind of stuff So what’s his observation? It is hot That’s his observation It’s really hot outside He has a hypothesis, what is it? (students voices chattering) That is hot enough on the sidewalk to fry an egg That’s a pretty specific hypothesis, and from his observation that this very well may happen Here’s where he gets into the experiment part Let’s dissect his experiment and we’ll pick it apart in a little bit How many eggs did he use? – One – One? How long do you let it sit there? (students voices chattering) Probably a couple seconds, not nearly long enough or whatnot He had to choose a spot on the sidewalk to do it in And he had to get a carton of eggs from somewhere and whatnot And there’s all these parameters, obviously, it could be done better How many eggs would you have used? How to use all of them? In fact, I did when I was his age Actually, twice that, according to my (mumbles) I would use all of them, large sample size, sample size, one not so good The timing of it, the choices of his location, what’s the variable that he may not have accounted for that you see in the first slide? – Under a tree – Yeah, maybe got some shade in that particular spot and so therefore, it’s not as hot You didn’t account for that So we maybe needed to distribute the eggs, all along the sidewalk like I did So, timing, let it go a little bit longer boy, it takes a lot longer even in a hot pan for it to cook like that How cooked did he want it to be? That was another factor that he didn’t address in his hypothesis or that he counted for, over easy or, a little bit burnt or whatnot Besides all of his problems with his experiment that we can definitely improve upon, what was his ultimate conclusion? Do you support or reject this hypothesis? – Reject – He rejected it So what was his new hypothesis? It’s hotter on the car dash So instead of is it hot enough to fry an egg on the sidewalk, he changed it to say, maybe it’s hot enough to fry an egg on the car dash Which is not a bad change of his hypothesis because, maybe intuitively like we know,

metal conducts heat lot faster than concrete does So not a bad change of his hypothesis But if he does it the same way he did here, he might still run into issues that he dealt with So that kind of gives you an idea, you will not have a Calvin and Hobbes quiz question But this is just to get you thinking about, the process of problem solving that we all do on a daily basis How do we approach an observation and our hypothesis about how the world works around us?