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Reading: Science — How-to Part 2

Video transcript

- [Voiceover] Now that we've read the passage, let's see if we can answer some questions around it. So, question number one: So, we remember that, if I remember correctly, the passage started with Adelita. Adelita was his turtle, and this 9,000-mile journey was across the Pacific Ocean from Mexico, from the West coast of Mexico, to Japan, so let's see what they're talking about. Well, she couldn't have used the North Atlantic gyre. They do talk about that later on in the passage as ways that turtles in the Atlantic navigate across the Atlantic, but Adelita, though, what the passage started with, she was navigating across the Pacific, so she's not gonna be using the current of the North Atlantic gyre. Well, they definitely talk about electromagnetic coils designed by Putman and Lohmann in the passage, and these researches used those coils to test whether turtles respond to it, that it effects their sense of direction, but Adelita didn't use the cues from electromagnetic coils. It's not like Putman and Lohmann were on a boat for 9,000 miles with, kind of, electromagnetic coils near Adelita and using that to tell Adelita how does she navigate her 9,000 mile journey. It's not like she had access to these things. She did it on her own. Well, yeah, well that's what the whole passage is about. It kind of starts off with, isn't it amazing that this turtle can navigate this 9,000 mile journey on its own without some type of a GPS device. And then it uses the research of Putman and Lohmann to show that turtles are able to do this by using the inclination intensity of Earth's magnetic field, so that looks right. Now, let's look at the last choice. Well, once again, this is like choice B. Adelita did not have access to technology from the researcher or Lohmann, so this is... She was off by herself in the Pacific. All right, number two. So, once again, the answer to the previous question is that turtles use the inclination and intensity of Earth's magnetic field. So, what's the best evidence for us to feel good about that? That turtles actually do use the inclination and intensity of Earth's magnetic field to navigate across the Pacific, or to navigate across an ocean. Let's see, lines one through three. So this is line one right over here. They give us every fifth line. Yeah, this is what they started off with. It was an amazing statement. This was kind of starts to serve the problem to it. Like, isn't this amazing? But how does this happen? But this doesn't give evidence or explain why or how they use the inclination and intensity so let me scroll back. That doesn't give evidence that they use the inclination and intensity of Earth's magnetic field, so I'm gonna cross that one out. Let's see, lines 30 to 32. Let's see, lines 30 to 32. Well, we later do use this, you know, Lohmann uses this technology that he's developed to test whether turtles respond but this sentence by itself isn't providing evidence. It's just starting to say that hey Lohmann can mimic magnetic fields at different parts of the Earth's surface, so I don't think that this is... I don't think this is evidence either. I'm sorry, I have to kind of keep scrolling back and forth like this. Let's see, 53 to 55. 53 to 55. So, let's see, that's this right over here. Well, if we remember, this is when they said, "Look, "the turtles use the magnetic field "and they might also use this other stuff." "You know, the stars, the position of the sea, sun and stars "might also help them," but once again this isn't evidence for us believing that they use Earth's magnetic field. These are just other things that they might use. So, let me just cross that one out. So, deductive reasoning, it's probably gonna be D, but let's check it out. Line 64, 64 to 67, starting with, "Neither," so that's right near the end. And when they're saying, "neither," they're talking about different parts of the world have unique combinations of these two variables, and those two variables are the intensity, the intensity of the magnetic field, and the angle of the magnetic field, so neither corresponds directly to either latitude or longitude. And when they're saying, "neither," they're saying neither the intensity or the angle. But together, they provide a magnetic signature that tells the turtle where it is. So, this is the closest that I would say to actually providing evidence that turtles, that the angle and intensity of a magnetic field can provide a signature to turtles to tell them where they are. So I like that one. It's actually the best of all of these, so I would go with D. All right, let's check out line three. Used in line three. So, he put a tag on this turtle and this was able to track it. So, let's see. Followed, not hunted. He's not trying to kill the turtles, or anything. It's not like he's traveling over the turtle, and it's not like he's... He's not searching for the turtle. He actually knows where the turtle is because he has a satellite tag on it. So he followed the turtle. Well, they seem to validate each other. They were both working on magnetic fields and how magnetic fields can be used by turtles to navigate. No, that's not the case. So, this one seems interesting. I'm actually gonna go back to the passage to make sure that it was Putman building on Lohmann versus Lohmann building on Putman. This could be interesting as well. It wasn't like, I mean, the passage said that Putman's research was wrong, so we can rule these two out, but let's revisit the passage a little bit, just so that we can make sure we understand the work. So, they told us, how did she, Adelita, steer across two oceans to find her destination? It says Putnam has the answer. So Ken Lohmann is his advisor. He's his mentor. So, I'm starting to feel that he probably built on the work of Ken Lohmann, 'cause Lohmann has been studying the magnetic abilities of loggerheads for over 20 years! So, Putman is a junior researcher, so I think he's building on the work. He's building on the work of Lohmann. He works in Lohmann's lab. Lohmann's been doing this for 20 years. So, let's see where they do that. Line 49. Reed. So, let's see. All right, so they're giving these other examples to say, "Hey, like, turtles are not the only ones "that have this mysterious ability." No, that's not what they're trying to do. Yeah, this is feeling pretty good. No, they're not saying most animals, they're just saying there are some other animal species that have this amazing ability, so they're not saying that most species. Let me just cross it out like this. No, they're not saying that the reed warbler or the sparrow, because they can travel long distance, are able to do this or that or find more food. They're just saying, "Hey, turtles are not the only one. "There's other species that also can do this." So, I'll cross that out. And I'd go with B.