Scientific Method & Measurement
Doing science means trying to figure out the answers to questions you have about the world around you. Like the Mythbusters are doing here on a beach. This is what happens when you challenge people try to build their own working personal hovercraft.
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Killer Laundry, Episode 10.
Science can include strange things, like collecting dog urine, as well as awesome stuff like explosions. But exploding dog urine? That combination sounds, well, rather implausible. Yet, the Mythbusters test it anyway. And Buster does an awesome Tasmanian devil impersonation.
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If you saw the Mythbusters yesterday, this picture makes perfect sense. If not, you are probably feeling confused right now, and a little concerned about what you've gotten into for this class. What IS this class, anyway? How is science different than any of the other subjects you study?
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Click below to read "What is science?"
Wait. What? Why do we have to learn about this? Well, there are SOME students who do things in the restroom here that I really hope they don't do at home. Like flushing. There are also some things we want to make sure you know about how to stay clean and not get dangerous bacteria on stuff. For each of the pictures below, think about if it shows things you should or should not do in the restroom, and why. But before we begin, click on the link below to find out what happens if an astronaut has to use the restroom on the moon....
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With an experiment, you are trying to figure out what might happen if you do something. Then, you try to explain why it did (or didn't) work. Like drinking radioactive sodium to see how fast it will circulate in your blood stream.
"Excuse me. Do you have this in fruit punch flavor?"
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Which pig do you think will win the race? Why? Think about all of the things that could happen between the time this picture was taken, and the finish line. Perhaps the lead pig gets hungry and leaves to find food, or trips, allowing a pig further behind to go past. All you can do is make a prediction, then watch what happens. The same thing is true for an experiment. You try to guess what will happen, then do the experiment and see if you were right or wrong.
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You are going to do a lab with marbles and ramps of different shapes. You will need to predict which ramp you think will be fastest before you roll them down the ramps. And, you will need to figure out how to start all of the marbles rolling at exactly the same time.
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So, you've finished doing your first lab. You needed the use of some of your senses (sight and touch) to be able to do it, and you needed specialized equipment (the ramps). With the assignment below, draw and describe examples of scientists using each of their 5 senses to do science stuff. Then, draw scientists using 3 different pieces of equipment or tools during their experiments.
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Click below to read "How science works."
Look! Up in the sky! It's a bird! It's a plane! It's ... a ... a ... Oh. It's a bird.
Scientists make observations about the world around them, using their senses. These observations can spark ideas about experiments. Often, specialized equipment is used as part of observing, such as binoculars or telescopes to see things that are far away, or microscopes to see things that are too small to see with just one's eyes.
In this picture, students are using binoculars. If you look closely, you can see that one of the students has what appears to be notes or a field guide hanging in a bag. For bird watchers, this would probably be a list (with pictures) of birds commonly found in the area.
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Once a scientist observes something, they should record their observations. Observations do not just need to be about living things, either. In this picture, the scientist could be recording temperatures, noting that there is snow on the ground, or describing rocks.
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This movie is famous for having a giant carnivorous (alien) plant as one of its stars. You can watch a trailer for it by clicking on the movie poster. Prepare yourself for singing.
The lab you will be doing does involve making observations about plants, but you don't have to worry about being eaten by them. You will be using several of your senses to make observations about succulents, which are like cacti, but without the spikes.
Want to see more horrors from the movie? The link below will take you to a page with photos of some incredible Lego designs that recreate certain famous scenes.
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Is the diver making observations of the shark, or is the shark observing the diver?
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As it would be a little expensive to fly all of you to South Africa for field work, you'll be watching great white sharks leaping into the air from the safety of your classroom. Instead of from a rather small boat.
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Science is not always just labwork. Sometimes you need to be able to read about science, too. By reading, you will be able to come up with new ideas to test, as well as learning more about subjects that interest you.
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I'll bet I can think of the question you have in your head right now while you are looking at this picture. Yup. Pretty positive that I can do that.
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When a new species is discovered, scientists will have a lot of questions. The crab you see here was discovered in 2006, deep on the ocean floor, living near active hydrothermal vents. Inspired by the bristles coating its arms, scientists decided to call it a Yeti Crab.
What the heck is a Yeti? Click on the link below to see a video about one that lives in Southern California.
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By clicking below, you can read about the initial discovery of the yeti crab, at hydrothermal vents off the coast of Costa Rica.
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Scroll to the bottom of the article linked below to see the first video footage of the yeti crabs found at hydrothermal vents off the coast of Costa Rica.
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More recently, yeti crabs have also been discovered near Antarctica. See what National Geographic has to say about them in a short video, liked below.
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Now that you have seen some images and video footage about them, it is your turn to ask questions about the yeti crab.
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It is not always easy to study things. Those mysterious yeti crabs live at the bottom of the ocean, so it is very difficult to bring them to the surface and study them. However, we can look at other animals that are easier to access, and observe how they use similar body parts.
Whales that have baleen in their mouths (think bristles, but much bigger than the ones on your toothbrush) use the baleen to help them eat. They take a huge mouthful of water, partly close their mouths, and force the water back out of their mouth through the baleen. These bristles catch everything from fish to plankton, which the whale then swallows.
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People use nets in a way similar to a whale using baleen. In this picture, a net has been selected with a lot of space between the strings of the net. These spaces allow water to flow out of the net, but the net strings keep the fish inside.
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Scientists have been able to observe yeti crabs, and discovered that the bristles on their arms seem to be used to capture yummy bacteria for food. The crabs wave their arms through the water, then clean off their arms with their mouth. However, it is way to expensive to bring yeti crabs to science class, so you are going to explore how different tools work to capture "bacteria" in a bowl of water.
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While you work on your lab, think about how lucky we are that crabs are usually pretty small. And do not possess psychic powers to make earthquakes. Or eat the scientists trying to destroy them with dynamite.
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ROVs (Remotely Operated Vehicles) are robots used for deep sea research. They are considerably cheaper to use than submarines carrying people, but they are still very expensive to operate (see the link lower down for an example of costs). There is also the advantage that they are much safer for the scientists.
ROVs rely upon complicated robotic arms to collect different kinds of data, ranging from oceanwater chemistry and temperatures to geologic and biologic samples. In the video clip linked below, you will see the ROV Hercules maneuvering a temperature probe into a hydrothermal vent.
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As you can probably imagine, designing, testing, and using ROVs can be pretty expensive. Instead of waiting until the ROV reaches the bottom of the ocean before finding out if new parts work or not, scientists test things out in the lab. With the lab below, you will try to figure out the best type of tool to use to sample worms from cracks in rocks, then recommend which tool works best.
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You know that cats like to hunt birds. But what will cats do when a really BIG bird gets into the yard? Leap at the window? Run away? Stay very still? You won't know until you watch what happens.
Your assignment, Prediction Practice, will help you to analyze predictions, and determine if they are good ones or not. For this example, a bad prediction would be that the cats would sing karaoke when they see the turkey. A good prediction would be something that you could test, and would be based on things you knew before. For example, if your cat always leaps at birds it sees through a window, a reasonable prediction would be that the cat would leap at the window because it sees the turkey (which is, of course, a bird).
"I'm not waiting until Thanksgiving."
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Your assignment, Prediction Practice, will also talk about algae in fish tanks. The picture here shows you what fish tank algae (the green stuff) can look like. The fish is called an Algae Eater, appropriately enough. If you look very closely at the left side of the pot, and at the narrow part towards the top of it, you can see clean parts where the fish has already eaten the algae.
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What a nice sign. Very informative. Now that you've analyzed some predictions, it is time to make some of your own. About surviving a zombie apocalypse. Instructions on the handout below.
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Think back to your first lab. Without realizing it, you were already doing your experiment in a logical manner. Now, you just need to put labels on the things that you did. Use the organizer below to do this.
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So... some animals can be trained to do tricks. That means that they are able to remember what to do when given certain cues by the person. The trainer will use a combination of gestures and sounds (and treats!) to enforce the idea that the animal doing something a particular way is a good thing.
"Now, where did I leave my keys?"
NOM NOM NOM NOM
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Goldfish Memory, Episode 12. The Mythbusters were wondering how good the memory of a goldfish is. They decide to see if it is possible to train goldfish to move through a maze to get their food. One of them is much better at this challenge than the other. And some fish are not that interested in flake food....
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You can actually buy a goldfish training kit. No kidding!
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Brainpop: Scientific Method
Tim and Moby experiment to figure out the best amount of watering for their plants. Things get squishy....
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As an example while discussing the scientific method, your textbook will refer to research about deformed frogs. An example of one of these frogs is shown here.
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Biscuit Bullet, Pilot Episode 2. Does biscuit dough feel like brains? The Mythbusters heat up a bunch of containers in Adam's car to find out. His interior will never be the same again.
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Penny Drop, Episode 4.
Tourists + the Empire State Building + spare change. Is this a lethal combination? Oh, and Adam gets shot in the butt.
One kind of data that scientists collect is measurements. In this example, the ornithologist (scientist that studies birds) could be measuring the length of the whole bird, the wingspan, feather length, beak length, or many other bird body parts.
Scientists use the metric system for their measurements to make them easily understood by other scientists throughout the world.
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Brainpop: Metric vs. Customary
We are used to using the customary method of measurement, with units like those in the picture. However, most other countries use the metric system, as do scientists around the world. And you'll see Moby get a royal complex.
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No, the mouse is not dead. It is just being held by the scruff of the neck to keep it still while a scientist measures how long it is using the metric side of the ruler.
"I am so gonna bite those fingers!"
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Most of what we know about giant squid usually comes from observations of dead ones that have washed up on a beach. Or from parts of ones (specifically, the beak) that are found in the stomachs of whales. It has only been recently that giant squid have been seen alive. Video of this moment is linked below. Notice how the scientists in the submersible get really quiet....
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Awesome! A giant rotting squid!
"Dude! Let's measure it! I'll get my string!"
(This is actually a pretty smart approach. Rotting squid slime is pretty hard to clean off. Why ruin a perfectly good measuring tape when you can slap a string on the corpse, then measure how much string was used?)
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A Humboldt squid, caught off of the coast of Southern California. It is also known by the name diablo rojo. They have been found to have a body size of 8 ft long (not counting tentacles) and weigh up to 100 lbs.
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Exactly how big can squid get? How dangerous are they? The writer Jules Verne explored this idea in his book, 20,000 Leagues Under the Sea. Disney made a movie of the book, way before the computer generated monsters of movies today. So, you can see a giant (puppet) squid attack. Click on the movie poster to get to a preview of the movie.
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Flying squid! They actually exist. But... how big are they? You can't tell from this picture because all we can see are the squid and the water below. When you do the exercise below, the diagram on it will help.
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To get some practice in measuring length, you will do a lab where you have to measure the sizes of a box full of different shells. But before you get started, you'll need some background information.
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Brainpop: Mollusks
The shells you will be measuring come from a variety of different mollusks. Watch this short cartoon to see what kind of animals lived in them.
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The mollusk that you are probably most familiar with is the garden snail. These animals protect their soft bodies by being able to withdraw into their shell. They've always got this armor on as they crawl around your garden. The shell is actually attached to their bodies; they cannot crawl away from it.
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Some snails live their entire lives underwater, instead of on land. Most of the shells you will measure are from sea snails like this one.
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The other kind of shell you will find in your box comes from clams. Instead of the single shell carried by the snail, clams have two shells that they are able to open and close. Just like a snail, to protect themselves from drying out or from predators, the clam is able to pull its body back into its shells. Notice how both the clam and the sea snail have a tube sticking out of their bodies. This is called a siphon, and is used to pull water into the animal so they can get oxygen out of the surrounding water.
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Meat is usually sold for a certain price per pound. The butcher will take its mass (weigh it) and then multiply the price per pound by the weight. You are probably used to seeing just the total price tag on the meat.
Some freshly-caught animals (like the lobsters shown here) are sometimes sold along the wharves where the fishing boats are tied up. The mass of the animal is taken right there, and you go home with dinner.
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For this image (and the one above) the scale that is being used is called a spring scale. When the object (in this case, a hedgehog) is placed upon the scale, a spring inside moves. How much the spring moves determines how much the pointer moves on the printed numbers.
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To measure extremely accurately (like during a scientific study) a digital scale is used. These scales can measure down to very tiny amounts of mass, like the fish that is in the picture. You will be using a digital scale when you do the lab below.
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Many animals have coloring on their bodies that makes it difficult to see them. For example, the two Tawny Frogmouth owls in this picture have feathers with coloring and patterns that helps them to blend right in with the bark on this tree.
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Humans can use camouflage to their advantage as well. By wearing uniforms that match their environment, and painting their faces, these 5 Marines are hard to spot in the forest.
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Cuttlefish are amazing creatures. Not only can their skin change color and pattern to match their environment, they also change their body shape and how they hold their tentacles. This particular cuttlefish in the Monterey Bay Aquarium.
Now watch the video clips below to learn how cuttlefish (and their relatives) are able to do such amazing camouflage tricks with their bodies.
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Here is a research lab for breeding danio fish. Notice that there are lots of tanks, tubing to add or remove water, and labels on each tank.
On the page below, design a lab where a scientist could study the camouflage capabilities of cuttlefish. Be sure to include tanks!