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This is TALK OF THE NATION: SCIENCE FRIDAY. I'm Ira Flatow.

President Bush visited a giant fuel depot in Brazil today, examining stalks of sugar cane, sniffing beakers full of diesel and alcohol made from the sugar cane. Brazil and the U.S. also announced today that they have signed an agreement to promote the development of biofuels in the Americas.

Now, no one is making alcohol from sugar cane in the United States. Here, corn is king. Acres and acres of land that might have grown corn headed for feed, fields that might have been left unplanted are now going toward ethanol as farmers, industrialists and Wall Street invest heavily on turning corn into biofuels.

Now there are a couple of problems with the headlong rush of corn to fuel in this country. First off, we can't grow enough corn to produce the ethanol that we would need to power all of our cars and trucks; and secondly, turning corn into alcohol cannot currently be done very efficiently.

It takes a lot of energy to get the raw materials, the fertilizing, the planting, the harvesting and transporting the corn. So the return is not terrific. Scientists are working to develop alternative methods and alternative fuels that can compete and even beat corn-based ethanol. And last week some of those efforts were rewarded.

The Department of Energy awarded $360 million in grants to companies working to develop cellulosic ethanol, made not from the edible parts of plants but from agricultural waste; and believe me, there is a lot of it. Still other efforts are focusing on butanol, which gives as much energy per gallon as gasoline, and biodiesel, a cleaner form of diesel made from plants like soybeans.

So this hour we're going to be talking about the promise of biofuels and the research and policy challenges that need to be met to bring those cleaner, greener fuels to the market. If you'd like to get in our discussion, you're welcome. Our number is 1-800-989-8255, 1-800-989-TALK. As always, you can surf over to our Web site at sciencefriday.com. We have other links about what we're talking about today.

Dan Kammen is co-director of Berkeley Institute of the Environment and professor in the Energy And Resources Group at UC Berkeley. And he joins us today from the UC Berkeley campus. Welcome back to the program, Dr. Kammen.

Dr. DAN KAMMEN (Energy And Resources Group, University of California, Berkeley): Oh, thanks for having me here.

FLATOW: You're welcome. Mitch Mandich is the CEO of Range Fuels, with offices in Palo Alto, California, and Broomfield, Colorado. He joins us today from Palo Alto. Welcome to the program, Mr. Mandich.

Mr. MITCH MANDICH (Chief Executive Officer, Range Fuels): Thanks, Ira. Good to be here.

FLATOW: Thank you. Jim McMillan is the manager of the Biorefining Process R&D Group at the National Bioengineering Center. That's at the giant national Renewable Energy Laboratory in Golden, Colorado. He joins us from his office there. Welcome to the program, Dr. McMillan.

Dr. JIM MCMILLAN (Biorefining Process R&D Group, National Renewable Energy Laboratory): Thank you very much. It's a pleasure to be here.

FLATOW: Dan, what do you think of the announcement today, the agreement between Brazil and the U.S.? Any big impact? Any big news here?

Dr. KAMMEN: Well, I think there will be an impact. Unfortunately, this is sort of a bit of a careening from one thing to another. We've finally got the message across that we don't want to be so dependent on oil, and so now there's this sort of excited, under-analyzed, headlong rush into Brazilian ethanol. And we had a lot better science available to us to allow us to rate fuels based on how good they are in terms of beating gasoline, in terms of the energy balance and the greenhouse gases, and the impact on water and poor people. And I wish the president had taken a moment to actually consider some of that information, which ironically was available to him before the 2006 State of the Union Address.

So this is interesting and it'll build up some markets, but it's really rushing ahead without letting the science of which fuels really are better and which ones are not as good lead us exactly at the time that California already has a standard called the Low Carbon Fuel Standard that does, in fact, take these into account. And in fact Governor Schwarzenegger and Senator McCain have already called for a federal version of it.

So there's a lot going on, and I'm very pleased to have seen - I was actually in D.C. last week for the announcement of the cellulosic plants getting some research money. And the reason why it's so important is because this country is building some 125 or so corn-based ethanol distilleries, and I believe with this federal money it brings the number of cellulosic ones, a process and a fuel that we know to be much better for the environment and much better on an energy and greenhouse-gas balance, I think we're at about 10 and most of those are quite small.

So we really need the White House to listen to a little better science right now.

FLATOW: Mitch Mandich, your company, Range Fuels, was one of the six to get a grant from the US DOE to develop cellulosic-based ethanol. Tell us why that technology and that road, that pathway is better than the corn-based.

Mr. MANDICH: Well, yeah. Well first, we're very pleased to have received the award, and you know, our company does not want to enter any debate around feed versus fuel. And if you look at consumption and gasoline consumption in this country, we consume about 140 billion gallons of gasoline a year, and corn ethanol has a maximum carrying capacity in this country to produce around 15 billion gallons a year of ethanol. So it really is finite.

And when you look at the feed versus fuel debate and the finite capacity of the product, we have to look at alternatives. So our company is focused on cellulosic ethanol, and we're going to use wood chips from Georgia pine trees that are really, basically, scrap material today, and parts of the trees that are left into the forest to decay or they're burned.

So it's a waste product that we're going to be able to use and turn it into fuel, and we're very excited about the prospects.

FLATOW: Our course, being done in Georgia means you could do it anywhere else in the country by setting up another plant in every state or other place where you can collect all the waste.

Mr. MANDICH: Yeah, and that's entirely true, Ira. And there's a great deal of pine trees in the Southeastern part of the United States that can produce upwards of 12 billion gallons of cellulosic ethanol every year just from the waste material, the residues.

If we look at the Northeast Atlantic Seaboard, we look at the Pacific Northwest, there's a tremendous amount. And in fact the U.S. Department of Energy has done several different studies around cellulosic material, and their analysis shows that this country could produce 140 billion gallons a year of ethanol from cellulosic products. And that would take us a long way toward energy independence and offsetting our need for fossil fuels to propel our cars.

FLATOW: Jim McMillan, could we get that much energy out of just the waste or would we grow crops for the cellulosic process?

Dr. MCMILLAN: To achieve anything close to that we would definitely be going into so-called energy crops, crops that were grown on what are now marginal agricultural lands that would be able to supply a significant amount of material.

FLATOW: The president has talked a lot about switchgrass. And there was a time back in the old West when prairies were covered with switchgrass as far as the eye could see, was there not?

Dr. MCMILLAN: Yes, indeed. And these prairie grasses are actually, you know, sort of back to the future. Over 150 years ago we were a biomass-based energy economy, and we seem to be moving back into that direction where biomass will play a significant role in our energy future.

FLATOW: Dan Kammen, these grasses and alternative sources get you a much bigger return for your buck, energy and environmentally speaking, don't they?

Dr. KAMMEN: They absolutely do. I mean our goal is to develop, as both of the other speakers have said, biofuels that do not require lots of petrochemical inputs, that are actually better for the environment in terms of reclaiming land, perhaps fixing nitrogen. There's a variety of things that we want, and to get that, we're going to have to actually set up the standards. And I fear that this rush to get corn ethanol in place, which has quite minimal energy benefits over gasoline and actually isn't particularly better than gasoline at all on the greenhouse gas basis, which we're really going to have to focus on. This is a case where it's very disappointing because, two years ago, our lab developed a model with the ungainly name of EBAMM. It's the name of my department - the Erg Biofuel Analysis Meta-Model that's free to download. Several western states already use it as sort of their default analysis tool. It allows you to look at cellulosic fuels and corn made from both the stock, the stover, and the other parts.

And this is a much clearer and a simpler way than to basically throw a lot of money at corn-based, which is going to keep the cellulosic community in quite a small box. Because even if - as you just heard, the potential's very large. With lots of the capital going to corn-based it's going to be hard for that to become the dominant sector, and that's really what we need energy wise and economically and environmentally.

FLATOW: 1-800-989-8255 is our number. Are there any other kind of fuels, Jim, that might be coming along besides just ethanol and matter how we make it?

Dr. MCMILLAN: Oh absolutely. I mean in our liquid transportation fuel market we have both gasoline that we're using a lot of today, and ethanol displaces gasoline. It can be mixed in and reduce our dependence on oil for gasoline. But we also have a significant amount of diesel. About 40 billion gallons is the number that runs - that's in my head. And so the biodiesel and thermo chemical routes to diesel-like fuels from biomass resources are also a significant opportunity. There's also other liquid fuels, as you mentioned, like butanol, that could be produced that would displace into the gasoline market.

FLATOW: In fact, butanol has been talked about as - I think that the DuPont company is going to invest heavily in making butanol. Butanol is an industrial cleaner now, is it not? But it has good characteristics to replace gasoline.

Dr. MCMILLAN: Yes, it's a good solvent, and so it's used that way industrially right now. And it's sort of a specialty chemical in that sense. I mean, it doesn't have the economics of a fuel, but yes it has attractive fuel properties. It doesn't mix with water as much as ethanol and it's got more energy content per gallon, so it's roughly equivalent to gasoline. And there's less modifications to some of the linings and so forth in the engines.

But on the other hand there's no infrastructure and bringing new fuels forward is a complicated process. So while it's attractive, it's a little bit out there I think to develop it to the point where we are anywhere close to where we are with ethanol.

FLATOW: 1-800-989-8255 is our number. We're talking with Jim McMillan from the National Renewable Energy Laboratory. Dan Kammen, professor in Energy and Resources Group at UC Berkeley at the Berkeley Institute of the Environment. Mitch Mandich of Range Fuels. Mitch, right before we go to the break, how soon can you put this money to work?

Mr. MANDICH: Well, we're going to be breaking ground in Georgia the first half of this year, so we submitted our - well, will submit our permits in the next week. We're very encouraged about our ability to build quickly and, you know, it's our assertion that we'll be the first commercial-scale cellulosic ethanol plant in the United States. And I think our technology based on thermal chemical conversation has a head start on the enzymatic approach, which a lot of our competitors are using, and we're very encouraged about our ability to succeed.

FLATOW: All right. We're going to take a short break, come back, take your questions about alternative energy sources. Stay with us. We'll be right back.

(Soundbite of music)

FLATOW: I'm Ira Flatow and this is TALK OF THE NATION: SCIENCE FRIDAY from NPR News.

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FLATOW: You're listening to TALK OF THE NATION: SCIENCE FRIDAY. I'm Ira Flatow.

We're talking this hour about biofuels with Mitch Mandich, CEO of Range Fuels, which has offices in Palo Alto and Broomfield, Colorado. Jim McMillan, manager of the Biorefining Process R&D Group. That's at the National Renewable Energy Laboratory in Golden, Colorado. Dan Kammen, co-director of the Berkeley Institute of the Environment and professor in the Energy and Resources Group at UC Berkeley. Our number, 1-800-989-8255. Let's get a phone call in. Hi Fran(ph). Welcome to SCIENCE FRIDAY.

FRAN (Caller): Oh hi. How are you doing?

FLATOW: How are you?

FRAN: I wanted to ask them if they had heard - I read in the Mexican papers that the cost of doing this corn is making the cost of the corn tortillas go up in price in Mexico and the people are real worried. So I was glad to hear about that plan that uses wood. I wondered if your speakers had heard about that raising the cost of corn. I mean, I don't think we should make people give up eating so that we can drive our cars.

FLATOW: Dan, what do you think?

Dr. KAMMEN: Well, I have heard the story. I have students in Mexico…

FRAN: Oh really? Cool.

Dr. KAMMEN: It is a real concern. And in fact that's really why what I said in the beginning is I think the case, and that is that we have much better science to try to do this right. And in fact we know how to use corn better, but I think the real excitement is in particularly what Mitch said, and that is that the opportunity to use what is currently waste materials. In fact, in many parts of the country we have to pay so-called tipping fees to get rid of some of these wood and municipal solid wastes and other materials.

And this is just a wonderful way to put that to good use; it essentially has a negative cost. And that's the sort of thing that if we were going to take a little more measured policy and look at the costs and benefits of so-called life cycle impacts - which is really what California doing, and a number of western states are signing on - we would discover those to be a more promising route than a headlong rush into just more corn ethanol because we happen to historically have grown a lot of corn.

FLATOW: Thanks for calling Fran.

FRAN: Oh that's great. Thank you.

FLATOW: Bye-bye. So you're basically saying if we recycle our wood products like we recycle our bottles, we could take them all and make that all into alcohol.

Dr. KAMMEN: Well we actually could. Right now, a few landfills do collect the methane gas that comes out of the decaying material and they make that into electricity. But many places don't. And in fact many places - the tipping fees, which is what you pay just to dump the waste, would already make this an exciting deal just right off. Now, that said, we do want to build up the market. We don't want to just wait and wait for the cellulosic technologies to come online in large numbers. And one of the good things we can do, actually, is that if you use the waste heat from making corn into ethanol, you can actually reduce the greenhouse gas impacts by about 50 percent.

And one of our students here at Berkeley, Rich Plevin, and others are working on that. Those are the kinds of things that, again, we could build into a portfolio if we only took the time to build a portfolio.

FLATOW: And who would build the portfolio?

Dr. KAMMEN: Well I would like to see the Department of Energy working with the Bureau of Land Management and the EPA, and I would really like to see it be based on which of the feed stocks can we grow without displacing food, as the caller so well said, and which of them are not fossil fuel fertilizer intensive. Because in a funny way in some parts of this country we've actually optimized corn production to use just about as much oil, as much petrochemical fertilizer as possible because of the subsidy structures. And a policy like California's Low Carbon Fuel Standard is a way to rank all fuels really based on their merits, because all biofuels are not created equal, just the way you can have gasoline from a relatively clean source or you can make it from tar sands or shale oil and make it really ugly. And we want science and we want what's better for our economy and the environment to rule the day, not just who happened to get into the game early.

FLATOW: Jim McMillan, any comment?

Dr. MCMILLAN: Well a couple of them. One of the award winners from the Department of Energy is this company BlueFire - their model of cellulose conversion as based on concentrated acid hydrolysis followed by fermentation. And they're looking at landfills where the material being received there is a tipping fee. People are paying to get rid of their materials. So it changes the cost structure. So that is moving forward and that's quite attractive, I think.

FLATOW: Let's talk about what's holding up the development. We keep hearing about well, when cellulosic ethanol comes online, when it gets working. Mitch, how do you make cellulosic ethanol? You said you used a different process. Tell us what that is.

Mr. MANDICH: Yeah, we use a thermal chemical conversion process, and at the highest levels it's actually quite simple to understand. We have a first step that takes the wood chip product as a solid, and through pressure, heat and steam we convert that to a gas, and it's called a synthesis gas. And from that stage we take the gas and we interact it with a chemical catalyst, and that interaction produces alcohols. And it not only produces ethanol, but we produce methanol, propanol and butanol. And we can select in a catalyst how we want that alcohol to be distilled and fractionated.

So we have a process that we think is much quicker to market, compared to an enzymatic approach. And at the same time, our process allows us to use virtually any carbon-based feedstock. So we can use municipal waste. We could use switchgrass. We could use coal. We could use olive pits, paper pulp and on. And in fact we've tested all of those products, and to the best of our knowledge we're the only company on the United States that's actually taken switchgrass and has produced ethanol.

FLATOW: Well why do you need a grant to do this? This sounds so wonderful, why can't you just get private investment and start making this stuff?

Mr. MANDICH: Well, we started with private investment. It's interesting, my background is the software industry in Silicon Valley and the hardware industry, and they're not very capital-intensive, especially software. When you look at the cost of these plants, you know, a corn ethanol plant for perhaps 50 million gallons a year of ethanol costs $75, $80, $100 million. So these plants are not inexpensive. So to have the ability of the federal government to help jumpstart that with new technology - there are no cellulosic ethanol plants in the world operating at commercial scale, so investors are a little bit shy. So with the governments fund…

FLATOW: We lost him. We'll get him back. I guess we just dropped the line. Let me go to Jim. I imagine you've been listening. How much different is the other way of making fuel, making alcohol? We lost him also. Let's see if we have - 1-800-989-8255 is our number. Let's see if we can get anybody on the phone - no listeners either. It's interesting that the president today - let me read to you a little bit of what was signed - the president talking about - do we have anybody on the line? Nobody. We're having technical difficulties, as we say in the business, and we've lost our lines. So let's talk a little bit about - wish I could get a phone caller in. We've lost those lines, too.

The president went to - just a recap - went to Brazil today and talked - and was showcasing, you know, fuels, biofuels. Because as he has said in his State of the Union and other places, that he believes that the government should be active in weaning us away from oil. Remember the president called - said we had an oil addiction and that we've got to get away from that. Well, the president is actually, I guess, a little bit greener than a lot of people give him credit for, because he has shown this ability to stand behind what he was talking about, at least in the biofuels industry. Many times he has gone to plants like he did here in Brazil, sniffing around beakers full of biodiesel and beakers full of ethanol, putting his weight behind the fact that he thinks that we should be changing our fuel system away from oil.

Other people also - critics have complained today, saying that the president was setting up, I guess, America's ethanol cartel. Or I guess there would be -under criticism from his critics that they're turning the United States and other Latin American - the Americas - into another OPEC of ethanol. So we'll see how people react to that. Mitch Mandich, you're back with us.

Mr. MANDICH: I am.

FLATOW: I'm sorry I've cut you off. You were talking about the economics.

Mr. MANDICH: I guess you didn't like what I said, Ira. Where did you lose me?

FLATOW: I don't know. Well let's talk - you were talking about how your system works when I said to you - I was talking about the economics of this. How fast can you get this going and do you think, you know, this is a profitable business?

Mr. MANDICH: Yeah, we think it's a very profitable business. And when we run the economics and compare ourselves to corn ethanol and its price per gallon, we think that we're going to be very competitive with corn ethanol. And there's a lot of discussion in D.C. in the Department of Energy and other sources that cellulosic ethanol will be at least two or three if not four or five times more expensive than corn. So the fact that we think that our first plant can be competitive is great news, I think. And then this is a very innovative technology, so we're going to iterate on this technology on an ongoing basis and improve our costs over time. And as far as getting started, we'll break ground this year…

FLATOW: Right.

Mr. MANDICH: And most of the enzymatic approaches in cellulosic ethanol are targeted for production in 2009.

FLATOW: Jim, let's talk about the other method of making cellulosic ethanol. What is that?

Dr. MCMILLAN: Well, the main other method is the biochemical approach. And I - I apologize. I got cut off a little bit so I missed some of that conversation.

FLATOW: Let's start from the beginning.

Dr. MCMILLAN: Well, so the thermo chemical approach is breaking down the material to this synthesis gas, which is basically a hydrogen and carbon monoxide-rich gas. The biochemical route breaks down the material to its molecular structure, its underlying molecular structure, so the sugars, the carbohydrates that are in cellulose and hemi-cellulose, breaking them down to their root sugars; and then those sugars can be fermented to the product of interest: normally ethanol, butanol is and other options. There are options beyond that as well.

FLATOW: We've heard farmers on this show say, you know, it is my understanding that you don't use the carbohydrates. You don't use the food that the animals eat. If you just take away the cellulose part and leave the food behind, we can still feed the animals that corn.

Dr. MCMILLAN: Absolutely. You're talking about, like, we harvest the grain.

FLATOW: Right.

Dr. MCMILLAN: Then we can use the remaining above-ground plant material, or a portion of it - the stalks, the leaves, the cobs and so forth, or the straw in the case of wheat - we can use that as the cellulosic resource. Absolutely.

FLATOW: Yeah. 1-800-989-8255 is our number. Dan, sorry to have lost you there.

Dr. KAMMEN: I'm back.

FLATOW: Let me ask you this question. The president said today - he was asked - that we know there's a 54 cent a gallon tax on ethanol coming in from Brazil. And he was asked to comment on that, and he said that basically don't go there. That's not a topic under discussion.

Dr. KAMMEN: Which of course is a funny comment because you're down there signing essentially an ethanol trade agreement and a, you know, excited statement about let's get all these South American countries to produce ethanol so we can import that instead of gasoline. Obviously, it has to be on the table, as well as do subsidies that exist for corn-based ethanol in the United States.

And to talk about an energy policy around a biofuel and not talk about the implicit and explicit subsidies that exist for certain ones and not others -Mitch, for example, is in a real disadvantage in terms of some of the major subsidies that exist for corn-based production. So it is hardly a topic that by any reasonable economic measure should be off the table and don't go there.

FLATOW: Is there any projection - if Mitch's projects come through, if cellulosic ethanol does come online, mainstream, has anybody made a reasonable projection of what percentage of our total fuel load this would take over and when it might happen?

Dr. KAMMEN: Well, there's actually quite a few. And my lab is one of the groups that does it, the Natural Resources Defense Council does, there's a number of university groups that are working on it. And while you heard from Mitch in the beginning that the potential is essentially there to think about 100 percent replacement of gasoline in the coming decade; I actually think it's more likely that we will see a world which is perhaps a third of our liquid fuels from good, clean, cellulosic sources. That would be a huge change.

And a third in the fullness of time would likely be plug-in hybrid vehicles now running off of the places where the grid is clean. Like in New York state and California, where there's low carbon sources on the grid.

And a third is likely to remain the fossil fuels because they have such an entrenched position, but hopefully those fossil fuels will be consumed but with appropriate offsets i.e. with a carbon tax so there's money going back to the economy in other areas. Or so that when you actually buy a fossil fuel at the pump you are paying a surcharge reflecting that carbon in it, which is really the end thing we are most concerned about in my opinion, not international security, whether we're importing oil from Saudi Arabia or ethanol from Brazil, but the greenhouse gas signature of our fuel.

FLATOW: We're talking about biofuels this hour on TALK OF THE NATION: SCIENCE FRIDAY from NPR News.

Dr. KAMMEN: I would add something, if I could.

FLATOW: Sure.

Dr. KAMMEN: And that's the efficiency side. You know, we're talking about all these supply options, but we know that our transportation infrastructure, for example, is quite inefficient. I mean we could have much higher efficiency vehicles. We could be using a lot less fuel in terms of the demand side. So that biofuels can play - I mean, I agree very much that's it's going to be multiple solutions and it will be a mixture of a lot of different approaches. Fuel is a very, very big market. But the efficiency plan is a very important thing to put that first because the cheapest BTU, the cheapest gallon, for sure, is the one that you don't use.

Mr. MANDICH: That's a really important point. And we haven't made our vehicle fleet ramp up in efficiency through any of our federal standards in decades now. And it's - you know, it's embarrassing when you compare U.S. cars to Europe. And it's not just embarrassing on a mile-per-gallon count; it just costs the U.S. billions of dollars that we don't need to spend if we actually requested companies to make more efficient vehicles. And they absolutely can, and they do for other markets.

So we're really making our own job much harder by not taking advantage of the opportunities that you just heard about.

FLATOW: Let's see if I can get one quick call in before we have to go. Let's go to Dino in Saline, Michigan.

DINO (Caller): Saline.

FLATOW: Saline. I don't know. I'm thrown off today. I should be giving you a salting.

DINO: It should be pronounced Saline. At any rate, Ira, thank you so much. A great show. I'm a common listener. If Rush Limbaugh has ditto-heads, what do we call those of us who listen to your show? You think up a name and tell us.

FLATOW: Smart.

(Soundbite of laughter)

DINO: Smart, yeah. Well, thank you. Here's my question. I'll take the answer off the air.

A number of years ago, I was interested in this very topic, namely biochemical conversion. And I happened to read that of all the crazy plants, cattails - or the carbohydrates in cattails - and Jerusalem artichokes were excellent feed stocks for making fuel alcohols. And I wonder if your guests can tell us about those and other feed stocks. Thank you. I'll take my answer off the air.

FLATOW: Thank you. What do you think, Jim?

Dr. MCMILLAN: Well, I would agree that - I mean, there's a variety of feed stocks we can use. And the food versus fuel issue is really important. I guess that the really big - I mean, all of these materials have - a lot of them have significant cellulosic portions, if not all of them are cellulosic in nature. And so they're excellent resources. What I would bring back to sort of the -not the policy but the framework side in some of the earlier discussions is that, you know, in addition to the Department of Energy and EPA and stuff, we have the USDA. And we really have to think that the old model of agriculture supplying food, feed, and fiber essentially to our economy is being changed. There's a paradigm shift. So now it's food, feed, fiber, and fuel.

FLATOW: All right.

Dr. MCMILLAN: And chemicals.

FLATOW: Very good point, to end on. I want to thank all of you for taking time to be with us. Jim McMillan, manager of the Biorefining process R&D Group at the Renewable Energy Laboratory in Golden, Colorado. Dan Kammen, co-director of the Berkeley Institute of the Environment, professor at UC Berkeley. And Mitch Mandich, CEO of Range fuels. Good luck to you, Mitch, in making your processes work.

Mr. MANDICH: Thank you, Ira.

FLATOW: Thank you. We're going to take a short break. When we come back we're going to switch gears and talk about that diet study that came out this week. Stay with us. We'll be right back after this short break.

I'm Ira Flatow. This is TALK OF THE NATION: SCIENCE FRIDAY from NPR News.

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