科学美国人60秒 SSS Hybrid Cars, Drosophila Maggots, the Tribal Mind.（在线收听）

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Welcome to Science Talk, the podcast of Scientific American magazine for the seven days starting April 19th. I am Steve Mirsky. This week on the podcast, Scientific American author Joseph Romm talks about the hybrid cars you will probably be driving one day soon. Journalist David Berreby discusses how we are hardwired to separate the world basically into the groups us and them and biologist Matthew Cobb talks about maggots. Plus, we'll—that's right…, maggots—plus, we'll test your knowledge about some recent science in the news.

First up, Joseph Romm, he got his doctorate in physics from M.I.T. and was an assistant secretary of the U.S. Department of Energy in the late 1990s; and with Andrew Frank, Romm wrote the article "Hybrid Vehicles Gain Traction" that appears in the April issue of Scientific American magazine. He is now with the clean-energy consulting firm Capital E and he spoke from his office in Washington, D.C.

Steve: Dr. Romm, thanks for being with us today.

Romm: My pleasure.

Steve: I was with the[a] group of people a few days ago and the subject of hybrid cars came up; and somebody there started talking about the fact—I thought this was pretty common knowledge—that if you buy a hybrid today you really have to keep it for quite a long time to recoup the added expense for the car, and he went on and on about that. And the point that I made in response was I think people buy hybrids because of a commitment to the environment or something that they are trying to say to themselves or about themselves; but in the future I think eventually everybody is going to be driving a hybrid.

Romm: Yeah! Absolutely, I mean I think for some reason people have got stuck in their mind that hybrid has to pay for themselves [in] and two or three years nobody asked you whether the sun roof or the leather upholstery or the XM radio paid for itself. I mean, the question is, is it a feature that gives you things that you want? And in this case hybrids allow you to reduce your oil consumption. I own a 2004 Prius.I go to the gas station half as often as I used to; that's worth a lot to me—I am reducing my greenhouse gas emission. But I think your point is exactly right— the one that we made in the article—clearly gasoline prices are likely to be higher five or ten years from now from [where] they are today where as the technology cost of hybrids is going to go down, so I think those two trends just about guarantee that we're going to see more and more hybrids down the road.

Steve: One of the technological advancements you discussed in the article is the advent of the plug-in hybrid. Let's talk about that for a while. When are we going to start seeing hybrids that you pull into the driveway and you actually plug them in from your home electricity source, and what is going to be the effect of having that available?

Romm: Well! I think there is a lot of excitement among consumers and people who want to reduce oil consumption and greenhouse gases. We say in the article that we expect a lot of these on the road in[by] 2020 timeframe, but you're going to see some early introduction of these cars in the next few years.

Steve: The article talks a bit about how the plug-in hybrid modifies the entire worldwide fuel equation. You want to talk about that a little bit?

Romm: Absolutely. Well right now we are stuck on using oil for transportation. I mean about 97 percent of all fuel for transportation in this country comes from petroleum and clearly we are running out of the cheap oil. The oil that lasts tends to be in unstable regions of the world, so we keep having these huge price spikes. People want to get off of oil. The question is what is the best fuel to replace oil with and there is really three possibilities that are widely considered, one of which is hydrogen. And you know we talked briefly about hydrogen in the article; I wrote a whole book called the Hype about Hydrogen. I don't think it is going to be hydrogen, so the other two alternatives are really electricity and biofuel like ethanol and I think the car of the future is going to combine those two. The nice thing about a plug-in is the car isn't all electric. It just has a short electric range that is going to satisfy most people most of the time, and then you don't need the huge amount of batteries and the huge expense of an all-electric vehicle. So I tend to think that a plug-in hybrid can also be a flexible-fuel vehicle and run on biofuel that's going to be the car of the future and that is sort of the point we make in the article.

Steve: What are the big things that are going to happen between now and 2020 to make 2020 that sort of transition year?

Romm: Well! I think that there are three things that are going to happen. One is obviously huge amounts of money are going in to better battery technology. The battery technology for cars is really undergoing a second revolution. The first revolution was from lead acid to the nickel-metal hydride batteries that allow the hybrids to really work. You're going to see the lithium batteries that are typically in your cell phone and your lap top, those are going to make the transition to cars because of hybrid and because of electronics. A lot of money is going into better electric motors, power electronics. So I just think the cost of the technology is going to go down; that's sort of point one. Point two—in the year 2020, the price of gasoline is going to be you know, three dollars and 50 cents a gallon or higher, and I think you're just not going to find very many people who think we're going to go back to a dollar and 50.

Steve: I've seen three-20[$3.20] just over the weekend here in New York.

Romm: Well! Indeed; and I am trying to be conservative here. Is it possible the price of gasoline in 2020 is going to be four dollars or more, absolutely; it's very hard to predict. But I think it's safe to say that it's not going to be lower than it is today and it's probably going to be substantially higher. So clear[ly], the higher the price of gasoline, the more competitive alternatives are. And I think the third point, which we just touch on briefly in the article, is global warming; and I think it's becoming painfully obvious to anyone who is paying attention to what's going on in the world, whether it's hurricanes, sea-level raise, or just raising temperatures that global warming is real and the nations of the world are going to have to get very serious about it. So I expect by 2020, there are going to be strong policies in place to push higher fuel economy; there's going to be a price for carbon dioxide and there is going to be push for alternative fuel. So I think all of these factors together are going to push people towards a hybrid vehicle in the first transition you know over the next 15 years and then a transition to plug-in hybrids after that.

Steve: Dr. Romm, thanks very much.

Romm: Sure; thank you.

Steve: In addition to his book, The Hype about Hydrogen, Romm is the author of "The Car and the Fuel of the Future", a report for the National Commission on Energy Policy. That report is available at www.energyandclimate.org (energy and climate—one word). Romm and Andrew Frank's article, "Hybrid Vehicles Gain Traction", is in the April Scientific American and can be purchased at our Web site, www.sciam.com, and if you’re Googling, Romm is spelled R-o-m-m.

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Now it's time to play TOTALL…….Y BOGUS. Here are four science stories, but only three are true. See if you know which story is TOTALL……. Y BOGUS.

Story number 1: A study found that the 2004 Boston Red Sox were chewing and spitting tobacco three times as much as their World Series opponents, the St. Louis Cardinals and more than last year's World Series teams, the White Sox and Astros.

Story number 2: By carefully hydrating, pitting, stuffing and then dehydrating prunes again, the prunes were made to carry maps [and]of secret documents that were sent in care packages to British prisoners in World War II.

Story number 3: Researchers at the University of Maine [have] who discovered a reddish subspecies of zebra mussel in Maine's sewage pipes and have given the mussel subspecies the name Rita Hayworth. It's a tribute to the redheaded movie star in the poster in the prison cell in the movie The Shawshank Redemption, which involved an escape through a sewer in Maine.

And Story number 4: Sinks and toilets in Cape Town, South Africa are currently infested by inch-long larvae of the drone fly, more unpleasantly known as rat-tailed maggots.

We'll be back with the answer. But first, speaking of maggots, Matthew Cobb has been speaking of maggots. He is a lecturer in animal behavior at the University of Manchester and he recently organized the Manchester Maggot Meeting devoted to the study of, well, maggots. To find out what's up with maggots, I called Cobb at his home in England.

Steve: Dr. Cobb, thanks for talking to us today.

Cobb: It's a great pleasure.

Steve: You organized the Manchester Maggot Meeting!

Cobb: Okay! Well it's the second in a series of biannual meetings that we've been organizing on the behavioral neurogenetics of Drosophila larvae, which sounds rather grander than Manchester Maggot Meeting. This time it was in Manchester, the previous one was in Germany. And these meetings are designed to enable [a] relatively small number of researchers—around about 70 or so in this meeting—to discuss, in a very informal way, their work on the behavior and the underlying genetic and neural patterns of control about behavior in the Drosophila maggot. And the Drosophila is—many of your listeners will know, but perhaps not all, was—the key organism selected by the founders of the science of genetics at the beginning of the 20th century to try and understand these new laws of genetics and to understand the way that character is transmitted from generation to generation. So we have used those flies for well over a century now, and recently people have begun to realize that they've got two organisms in one. It's also the maggot which is much, much simpler and that's the reason why we study it.

Steve: So we're very specific. It's only fruit fly maggots here. We're not talking about blowfly maggots—your C.S.I. maggots (laughs) are not involved. It's just fruit fly maggots.

Cobb: Yes! Everybody was talking about what we called the Drosophila, Drosophila melanogaster. It's a Latin name, the Drosophila fruit fly maggots.

Steve: Can you talk about some of the specifics that either came up at the meeting or the specifics about what you can learn from these maggots?

Cobb: So, for example, what I work on is the sense of smell. I'm particularly interested in the sense of smell and how any animal goes from detecting particular molecules in the air or in the water; and then encoding that information, finding particular bits of the smell that are important, how it's represented in its brain and how it then responds to that. Now what's interesting is that we know from the work of the 2004 Nobel Prize winners, Linda Buck and Richard Axel, that each neuron—each sensory neuron—expresses a single type of olfactory receptor, and those olfactory receptors then take a particular part of the smell that they can detect and send the signal up to the brain, which is then processed; and essentially the same processes are taking place in your nose and a maggot's nose. So we can actually compare and try and understand things about how senses, smells, are processed from a maggot and see those same ways of extracting information being applied in human beings. The great advantage is that a maggot, as I am sure most of you this is what realized is very, very simple. It's a very simple organism. You and I have about ten million of these receptor neurons in our nose. A fly, the adults has about 1,300. A maggot has only 21, but it uses exactly the same principles; so we can study this very simple system and try and understand what the principles of sensory extraction of information from the environment, and how it's represented in the brain. If the maggot has a brain, it may be a small one, but it's still a brain with the same kinds of structures as in a human being, so that's one example. Another example which has been part of the biggest success work I think of over the last two years since the last meeting is the work of a group around Michael Pankratz in the U.S., research[ing] and now working in Germany in Karlsruhe University. He has worked on hunger, because obviously the most important thing to a maggot is to eat. And he has been looking at the kind of genes which are involved in responding to being hungry—its kind of the hungry maggot. And he's found a very few, very limited number of genes which are involved in regulating the animal's response to hunger; and these are expressed in a very small number of neurons which in fact control the animal's starvation response—how it responds when it is hungry. And the fascinating thing is that these genes are homolog[ous]—very, very similar—in mammals; and if you affect those genes in mice, you get a big fat mou[se]th. So it seems those, some of the character[i]s[tics] that you can see in a maggot—like hunger, like smell—are involved in mammals and even in human beings.

Steve: And the idea there, if there is any application to ever be had is to somehow get a handle on the obesity epidemic?

Cobb: I think that's what Mike was interested in, and I quite understand the philosophy. Very important work from the social point of view; it is absolutely fascinating from a scientific point of view. One of the great privileges of being a scientist is that you get to be curious—you are paid to be curious and try and find stuff out and every now and again it has [an application]n't applied taking on which kind of doubles the fun.

Steve: I see on the program that you gave the talk entitled, "Maggots through History".

Cobb: (laughs)

Steve: Can you briefly summarize that?

Cobb: Yeah! I have another life which is as the[a] historian of science and I've just published a book in the U.K. and most of the world, which is called in English—in the U.K. English version—The Egg and Sperm Race, which is about how we discovered the laws of sex life and drugs in 17th century and its is going to be published in a site,[slightly] different [title]type in [the] U.S. later in a[the] year. And in fact one finding out where tiny maggots came from was a decisive step forward in realizing where life comes from. Because up until the middle of the 17th century, people thought that maggots in particular and all small animals [were]which is generated spontaneously; and so in my relaxation talk, as you told, talked about it, I told about some 17th-century science and described the experiments that [of] some of the fantastic figures in the 17th century [that] were largely forgotten including [in] the scientific community. The experiments that they carried out demonstrate that maggots in fact come from eggs, which come from a female laid, eggs which are laid by the female of the same species.

Steve: I vaguely recall [from] my high school biology spontaneous generation, where people thought that life could arise out of pieces of rotting meat.

Cobb: Well! That's it. Well and if you think about it, if you don't look too closely, that's what happens. If you leave some meat out or some food out then all of a sudden, you find maggots or flies—where do they come from? There are a lot of biblical stories. For example the story of Samson, who sees the lion, the dead lion; it's got bees that have grown out of it and in classical literature like Ovid and Homer there are stories about this as well. So this is something that people believed for a very long time and casual observation just suggests that these tiny things come from nowhere; and it actually took some from very careful observation and some good experiments to demonstrate that this wasn't the case.

Steve: To see that there were female flies that were laying eggs in that rotting meat?

Cobb: That's right! What is interesting finally, is that ultimately life did appear spontaneously because at some point on the planet earth, matter, chemicals turn into life and so at least once in the history of universe, spontaneous generation did happen; but as Darwin himself pointed out—this is carrying on now—that would be a rather unfortunate fate for any kind of proto-organism that spontaneously generated; it would be eaten.

Steve: (laughs) Right! Dr. Cobb, it was a pleasure to talk to you today. Thanks very much.

Cobb: You're welcome.

Steve: Matthew Cobb's new book in the U.S. will be called Generation: The 17th-Century Scientist[s] Who Unravel[ed] the Secrets of Human Reproduction; it comes out in August in the U.S. and is currently available for preorder. We'll be right back.

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Novartis…. Think what's possible.

Steve: Now it's time to see which story was TOTALL…….Y BOGUS. Let's review the four stories.

Story number 1: The Red Sox chewed more tobacco than the other three teams in the last two World Series.

Story number 2: Special stuffed prunes were World War II's secret weapons.

Story number 3: Maine researchers named a red subspecies of zebra mussel for Rita Hayworth.

And story number 4: Cape Town is battling a rat-tailed maggot infestation.

Time is up.

Story number 1 is true. The Boston Globe reports that [the] 2004 Red Sox chewed more tobacco than the Cardinals that year or the White Sox or Ast[r]os in [the] 2005 World Series. That's according to researchers at the Harvard School of Public Health who analyzed video from the World Series. They did the study to publicize the continuing presence of chewing tobacco in baseball despite its being linked to cancer, gum disease and nicotine addiction.

Story number 2 is true. They did hydrate prunes, replaced the pits with maps and documents, dried them out again and send them to prisoners of World War II. This plum story came out last week because two of the surviving prunes are [set]said to be auctioned.

And story number 4 is true. There are rat-tailed maggots in the water in Cape Town. Reuters reports that a public health official downplayed the problem saying, "Since the rat-tailed maggot is quite large and clearly visible to the naked eye, it is highly unlikely that it would be ingested in the first place."

All of which means that the story about a new red subspecies of zebra mussel in Maine being named for Rita Hayworth is unfortunately TOTALL…….Y BOGUS. And if you got that wrong, you can put the blame on Maine.

Steve: Next up a discussion of tribes. Journalist David Berreby is the author of the book, Us and Them: Understanding Your Tribal Mind, which is reviewed in the current issue of Scientific American Mind magazine. To find out a little more about us and a lot more about them, I called Berreby at his home in Brooklyn, New York.

Steve: Hi, David. How are you?

Berreby: Good, Steve. How are you?

Steve: I am okay. Coincidentally just before calling you, I heard an ad for the radio station I was listening to, on that station obviously, and the announcer said, there is radio for them and there is radio for us.

Berreby: (laughs)

Steve: Who are us and who are them, or who are they? Who are we? And who are they? I should say.

Berreby: Yeah! That's actually—that's a great example of how even though, of course we have lots of different kinds of affiliations and they are not all the same and they do matter. If religion is not the same thing as race, it's not the same thing as nationality; and yet there is an aspect to all these questions that is heard and I think I would group them in the way that the mind is set up. And I think that what you are talking about there is a really good example of how we can think about whose on my team; or feel rather—which is in more accordance with the emotions of whose on my team—and who really doesn't belong here, about anything. You know, someone can get those buttons pushed with very, very little effort, so that it's not just a matter of who you should marry or who you should vote for, but things like, you know, you are an SUV kind of a person or minivan kind of a person, or you're this kind of radio station or that kind of radio station.

Steve: And you have in the book—in addition to the sections that you spent talking about culture—there are three chapters devoted to an analysis of the neuroscience that's behind this business. And you talk about how the brain actually seems to be hardwired to be making these differentiations; and that's probably a good thing.

Berreby: I think we cannot help but code up in any situation as we look around—well, what are the teams here, who might be on my side and who is not on my side; and we have a lots and lots of ways to take in information about that and we process those cues very, very quickly, even though the situations can change and therefore the groups that we perceived can change.

Steve: In keeping with what you were just talking about. Let me read a couple of sentences from the book.

Berreby: All right.

Steve: You say, "This does not mean that certain human kinds are real while others are not, but it does mean that human kinds with attributes that satisfy the kind code, the hardwiring, will be easier to think about and easier to feel right about than others."

Berreby: One of the things that comes out of the neuroscience chapter is that it's an error to think that the simple physical, old reactions that are in the brain like a reflex or taking a hand off the fire, those are some how more true and more deep and more profound and powerful than higher-level processing. So the brain works in both directions—the highways go both ways. And though yes, it's true that skin color is more apparent than social class and therefore in some sense that's a more easy way to think about people; but it's also true that if you convince me that class is the most important thing in the world, or you convince me that Christ is the most important thing in the world, you can undo the color perceptions; because the mind also works top down, changing what's going on below as well as bottom up, changing what's going [on] above.

Steve: So can being aware of our natural tendency to judge people very quickly or judge the group very quickly and figure out whether we're in that group or in the other group, can being aware of that be beneficial in terms of us not necessarily getting a le[d]t around by the nose so easily?

Berreby: Yeah! I think so. I hope so. I do think the[re] are some signs of that. But I think there are lot of good things about feeling like you have this profound connection and nourishment from your affiliation with other people who are part of something bigger than you are; so you're not trapped in this little tiller of yourself—it can be a very positive thing. But I think that if you keep in mind that it is something that changes a lot and it's something that is happening in your mind without you really consciously deciding to like or dislike this group of people or to see these people in this particular light, if you keep that in mind, then I hope and I think that people would be less able to be manipulated by someone. But someone says, you know, there is a gene for anti-Croatian sentiment, as the former president of Croatia tried to claim. I think if you're aware of how the research over the last 20 years, you will realize that genetically and psychologically it's ridiculous and that might make you a little less likely to buy into that kind of litany.

Steve: Very interesting. The book is Us and Them: Understanding Your Tribal Mind. David Berreby, thanks very much.

Berreby: Thank you very much.

Steve: David Berreby's Web site is davidberreby.com, that's d-a-v-i-d-b-e-r-r-e-b-y.com. Us and Them was also reviewed in the December issue of Scientific American magazine. You can find that review in the past issue section at our Web site, www.sciam.com

Interested in the inner workings of the human brain? Scientific American Mind magazine brings you breakthroughs in psychology, neuroscience and more. For a free preview, visit, www.sciammind.com.

Well, that's it for this edition of the Scientific American podcast. Our e-mail address is [email protected]; and also remember that science news is updated daily on the Scientific American Web site, www.sciam.com. For Science Talk, the podcast of Scientific American magazine, I am Steve Mirsky. Thanks for clicking on us.