TPO 6 Lecture 2 Biology 　　Narrator 　　Listen to part of a lecture in a biology class. 　　Professor 　　Ok, I have an interesting plant species to discuss with you today. Um…it’s a species of a very rare tree that grows in Australia, Eidothea hardeniana, but it’s better known as the Nightcap Oak. Now, it was discovered only very recently, just a few years ago. Um… it remained hidden for so long because it’s so rare. There are only about 200 of them in existence. They grow in a rain forest, in a mountain rage…range in the north part of New South Wales which is a…er… state in Australia. So just 200 individual trees in all. 　　Now another interesting thing about the Nightcap Oak is that it is…it represents…er…a very old type…er…kind of tree that grew a hundred million years ago. Um, we found fossils that old that bear remarkable resemblance to the tree. So, it’s a primitive tree. A…a living fossil you might say. It’s relic from earlier times and it has survived all these years without much change. And it…it’s probably a kind of tree from which other trees that grow in Australia today evolved. Just to give you an idea of what we are talking about. Here’s a picture of the leaves of the tree and its flowers. I don’t know how well you can see the flowers. They’re those little clusters sitting at the base of the leaves. 　　Okay, what have we tried to find out about the tree since we’ve discovered it? Hum…or how…why is…is it so rare? That’s one of the first questions. Um… how is it…um…h(huán)ow does it reproduce? This’s another question. Um, maybe those two questions are actually related. Jim? 　　Student 　　Hum …I don’t know. But I can imagine that…for instance, seed disposal might be a factor. I mean if the…er…you know, if the seeds cannot really disperse in the wild area, then, you know, the tree may not colonize new areas. It can’t spread from the area where it’s growing. 　　Professor 　　Right. That’s…that’s actually a very good answer. Um, of course, you might think there might not be any areas where the tree could spread into, er…because…um…well, it’s very specialized in terms of the habitat. But, that’s not really the case here. Um…the suitable habitat, that is, the actual rainforest is much larger than the few hectares where the Nightcap Oak grows. 　　Now this tree is a flowering tree as I showed you. Um…um…it produces a fruit, much like a plum. On the inci…inside there’s a seed with a hard shell. It…it appears that the shell has to crack open or break down somewhat to allow the seed to soak up water. You know, if the Nightcap Oak remains…if their seeds remain locked inside their shell, they will not germinate. Actually, the seeds…er…they don’t retain the power to germinate for very long, maybe two years. So there’s actually quite a short window of opportunity for the seed to germinate. So the shell somehow has to be broken down before this…um…germination ability expires. And…and then there’s a kind of rat that likes to feed on the seeds as well. So, given all these limitations, not many seeds that the tree produces will actually germinate. So this is a possible explanation for why the tree does not spread. It doesn’t necessarily explain how it became so rare, but it explains why it doesn’t increase. 　　OK, so it seems to be the case that the species, this Nightcap Oak is not very good at spreading. However, it seems, though we can’t be sure, that it’s very good at persisting as a population. Um…we…there’s some indications to suggest that the population of the Nightcap Oak has not declined over the last er…you know, many hundreds of years. So it’s stayed quite stable. It’s not a remnant of some huge population that is dwindled in last few hundred years for some reason. It’s not necessarily a species in retreat. 　　Ok, so it cannot spread very well, but it’s good at maintaining itself. It’s rare, but it’s not disappearing. 　　Ok, the next thing we might want to ask about the plant like that is what chances does it have to survive into the future. Let’s look at that.TPO 6 Conversation 2 　　Narrator 　　Listen to a conversation between a student and a professor. 　　Student 　　Professor Martin? 　　Professor 　　Uh, hi, Lisa, what can I do for you? 　　Student 　　Well, I’ve been thinking about, you know, what you were saying in class last week, about how we shouldn’t wait until the last minute to find an idea and get started working on our term paper. 　　Professor 　　Good, good, and have you come up with anything? 　　Student 　　Well, yeah, sort of. See, I’ve never had a linguistics class before, so I was sort of, I mean, I was looking over the course description and a lot of the stuff you described there, I just don’t know what it is talking about, you know, or what it means. But there was one thing that really did jump out at me 　　Professor 　　Yes? 　　Student 　　The section on dialects, cos…like, that’s the kind of thing that’s always sort of intrigued me, you know? 　　Professor 　　Well, that’s certainly an interesting topic. But you may not realize, I mean, the scope... 　　Student 　　Well, especially now, cos I’ve got like one roommate who is from the south and another one from New York. And we all talk like totally different, you know? 　　Professor 　　Yes, I understand. But… 　　Student 　　But then I was noticing, like, we don’t really get into this till the end of the semester, you know. So I… 　　Professor 　　So, you want some pointers where to go for information on the subject? Well, you could always start by reading the chapter in the book on social linguistics. 　　That will give you a basic understanding of the key issues involved here. 　　Student 　　Yeah, that’s what I thought. So I started reading the chapter, you know, about how everyone speaks some dialect of a language. And I’m wondering like, well, how do we even manage to understand each other at all? 　　Professor 　　Ah, yes, an interesting question. You see… 　　Student 　　So then I read the part about dialect accommodation. You know, the idea that people tend to adapt their speaking to make it closer to the speech of whomever they’re talking to, and I’m thinking, yeah, I do that when I talk with my roommates, and without even thinking about it or anything, you know. 　　Professor 　　OK, all right. Dialect accommodation is a more manageable sort of topic. 　　Student 　　So I was thinking like, I wonder just how much other people do the same thing. I mean, there are students here from all over the place. Does everyone change the way they talk to some degree depending on whom they are talking to? 　　Professor 　　You’d be surprised. 　　Student 　　So, anyway, my question is, do you think it’d be OK if I did a project like that for my term paper? You know, find students from different parts of the country, record them talking to each other in different combinations, report on how they accommodate their speech or not, that kind of thing? 　　Professor 　　Tell you what, Lisa, write me up a short proposal for this project, how you’re going to carry out the experiment and everything, a design plan. And I think this’ll work out just fine.TPO 6 Lecture 3 Creative Writing 　　Narrator 　　Listen to part of a lecture in a creative writing class. 　　Professor 　　Alright everybody, the topic for today is, well, we're gonna take a look at how to start creating the characters for the story you're writing. One way of doing that is to come up with what's called “a character sketch”, I don't mean a sketch like a drawing, I guess that's obvious. It's um…it's a…a sketch as a way of getting started on defining your characters' personalities. 　 　　To begin, how do we create fictional characters? We don't just pull them from thin air, do we? I mean we don't create them out of nothing. We base them, consciously or unconsciously, we base them on real people, or we blend several people's traits, their attributes into one character. But when people think fiction, they may assume the characters come from the author's imagination. But the writer's imagination is influenced by… by real people, could be anyone, so, pay attention to the people you meet, someone in class, at the gym, that guy who is always sitting in the corner of the coffee house, um… your cousin, who's always getting into dangerous situations. We're pulling from reality, gathering bits and pieces of real people. You use these people, and the bits of behavior or characteristics as a starting point as you begin to sketch out your characters. 　　Here is what you should think about doing first. When you begin to formulate a story, make a list of interesting people you know or have observed. Consider why they're unique or annoying. Then make notes about their unusual or dominant attributes. As you create fictional characters, you'll almost always combine characteristics from several different people on your list to form the identity and personality of just one character. Keeping this kind of character sketch can help you solidify your character's personality, so that it remains consistent throughout your story. 　　You need to define your characters, know their personalities so that you can have them acting in ways that are predictable, consistent with their personalities. Get to know them like a friend, you know your friends well enough to know how they'll act in certain situations, right? Say you have three friends, their car runs out of gas on the highway. John gets upset. Mary remains calm. Teresa takes charge of handling the situation. And let's say, both John and Mary defer to her leadership. They call you to explain what happen. And when John tells you he got mad, you're not surprised, because he always gets frustrated when things go wrong. Then he tells you how Teresa took charge, calmed him down, assigned tasks for each person and got them on their way. Again, you're not surprised. It's exactly what you'd expect. Well, you need to know your characters, like you know your friends. If you know a lot about a person's character, it's easy to predict how they'll behave. So if your character's personalities are well defined, it will be easy for you as the writer to portray them realistically…er… believably, in any given situation. 　　While writing character sketches, do think about details. Ask yourself questions, even if you don't use the details in your story, um…what does each character like to eat, what setting does each prefer, the mountains, the city, what about educational background, their reactions to success or defeat, write it all down. 　　But, here I need to warn you about a possible pitfall. Don't make you character into a stereotype. Remember the reader needs to know how your character is different from other people who might fall in the same category. Maybe your character loves the mountains and has lived in a remote area for years. To make sure he is not a stereotype, ask yourself how he sees life differently from other people who live in that kind of setting. Be careful not to make him into the cliché of the “ragged mountain dweller”. 　　Okay, now, I'll throw out a little terminology. It's easy stuff. Major characters are sometimes called “round characters”. Minor characters are sometimes called, well, just the opposite, “flat”. A round character is fully developed; a flat character isn't, character development is fairly limited. The flat character tends to serve mainly as a motivating factor. For instance, you introduce a flat character who has experienced some sort of defeat. And then your round, your main character who loves success and loves to show off, comes and boasts about succeeding and jokes about the flat character's defeat in front of others, humiliates the other guy. The flat character is introduced solely for the purpose of allowing the round character to show off.TPO 6 Lecture 4 Earth Science 　　Narrator 　　Listen to part of a lecture in an earth science class. 　　Professor 　　We’re really just now beginning to understand how quickly drastic climate change can take place. We can see past occurrences of climate change that took place over just a few hundred years. Take uh… the Sahara Desert in Northern Africa. The Sahara was really different 6,000 years ago. I mean, you wouldn’t call it a tropical paradise or anything, uh…or maybe you would if you think about how today in some parts of the Sahara it…it only rains about once a century. Um… but basically, you had granary and you had water. And what I find particularly interesting and amazing really, what really indicates how un desert-like the Sahara was thousands of years ago, was something painted on the rock, pre-historic art, hippopotamuses, ‘cos you know hippos need a lot of water and hence? Hence what? 　　Student 　　They need to live near a large source of water year round 　　Professor 　　That’s right. 　　Student 　　But how is that proved that the Sahara used to be a lot wetter? I mean the people who painted those hippos, well, couldn’t they have seen them on their travels? 　　Professor 　　Okay, in principal they could, Karl. But the rock paintings aren’t the only evidence. Beneath the Sahara are huge aquifers, basically a sea of fresh water, that’s perhaps a million years old filtered through rock layers. And…er…and then there is fossilized pollen, from low shrubs and grasses that once grew in the Sahara. In fact these plants still grow, er…but hundreds of miles away, in more vegetated areas. Anyway, it’s this fossilized pollen along with the aquifers and the rock paintings, these three things are all evidence that the Sahara was once much greener than it is today, that there were hippos and probably elephants and giraffes and so on. So what happened? How did it happen? Now, we’re so used to hearing about how human activities are affecting the climate, right? But that takes the focus away from the natural variations in the earth climate, like the Ice Age, right? The planet was practically covered in ice just a few thousand years ago. Now as far as the Sahara goes, there is some recent literature that points to the migration of the monsoon in that area 　　Students 　　Huh????? 　　Professor 　　What do I mean? Okay, a monsoon is a seasonal wind that can bring in a large amount of rainfall. Now if the monsoon migrates, well, that means that the rains move to another area, right? So what caused the monsoon to migrate? Well, the answer is：the dynamics of earth’s motions, the same thing that caused the Ice Age by the way. The earth’s not always the same distance from the sun, and it’s not always tilting toward the sun at the same angle. There are slight variations in these two perimeters. They’re gradual variations but their effects can be pretty abrupt. And can cause the climate to change in just a few hundred years. 　　Student 　　That’s abrupt? 　　Professor 　　Well, yeah, considering that other climate shifts take thousands of years, this one is pretty abrupt. So these changes in the planet’s motions, they called it “the climate change”, but it was also compounded. What the Sahara experienced was um…a sort of “runaway drying effect”. As I said the monsoon migrated itself, so there was less rain in the Sahara. The land started to get drier, which in turn caused huge decrease in the amount of vegetation, because vegetation doesn’t grow as well in dry soil, right? And then, less vegetation means the soil can’t hold water as well, the soil loses its ability to retain water when it does rain. So then you have less moisture to help clouds form, nothing to evaporate for cloud formation. And then the cycle continues, less rain, drier soil, less vegetation, fewer clouds, less rain etc. etc.. 　　Student 　　But, what about the people who made the rock paintings? 　　Professor 　　Good question. No one really knows. But there might be some connections to ancient Egypt. At about the same time that the Sahara was becoming a desert… 　　Student 　　Uh-huh 　　Professor 　　5,000 years ago, Egypt really began to flourish out in the Nile River valley. And that’s not that far away. So it’s only logical to hypothesize that a lot of these people migrated to the Nile valley when they realized that this was more than a temporary drought. And some people take this a step further. And that’s okay, that’s science and they hypothesize that this migration actually provided an important impetus in the development of ancient Egypt. Well, we’ll stay tuned on that.