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NOVA scienceNOW

PBS Airdate: January 10, 2006
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ROBERT KRULWICH: Hi, I'm Robert Krulwich for NOVA scienceNOW, and these things you see all around me here, they represent the top 100 science stories selected by Discover magazine for 2005. So we're going to mosey around, and we're going to choose the ones that we like the best, as we head into the New Year, for this special episode of NOVA scienceNOW.

For example, what are the chances that the virus that causes bird flu will develop the ability to move from person to person easily on a cough or a sneeze?

What you don't know is a lot.

KANTA SUBBARAO (National Institutes of Health): That's true.

ROBERT KRULWICH: We propose an unusual experiment and come up with an answer.

And can you create embryonic stem cells without creating an embryo?

RUDOLF JAENISCH (Whitehead Institute): The experiment worked very straightforward. It was actually very surprisingly simple to us.

ROBERT KRULWICH: An M.I.T. scientist thinks he can and hopes this new technique will heal the bitter divide over stem cell research.

FATHER THOMAS BERG (The Westchester Institute): Those of us who do not want to live with a future of embryo-destructive research, we might have a way out.

ROBERT KRULWICH: And...

NEIL deGRASSE TYSON (American Museum of Natural History): This is hate mail that I have gotten from elementary school children, handwritten letters, saying, "Please, Dr. Tyson..."

ROBERT KRULWICH: Who decides if this is or is not a planet?

MIKE BROWN (California Institute of Technology): This will absolutely rewrite the history of astronomy.

ROBERT KRULWICH: There is something new out there, but what is it?

And we examine a 2,000 year old mathematical mystery, musically.

ROB MORSBERGER (Correspondent, Singing): All of this and a whole lot more.

ROBERT KRULWICH: ...on this episode of NOVA scienceNOW.

Google is proud to support NOVA in the search for knowledge: Google.

Major funding for NOVA ScienceNOW is provided by the National Science Foundation, America's investment in the future.

And the Howard Hughes Medical Institute, serving society through biomedical research and science education: HHMI.

Additional funding is provided by the Alfred P. Sloan Foundation, to enhance public understanding of science and technology; the George D. Smith Fund; and the Kavli Foundation, advancing scientific knowledge at leading universities worldwide.

And by the Corporation for Public Broadcasting, and by contributions to your PBS station from viewers like you. Thank you.

10TH PLANET

ROBERT KRULWICH: Big news in the neighborhood. This is our solar system. And a couple of years ago, almost everybody would have told you that orbiting our Sun you would find one, two, three, four, five, six, seven, eight, nine planets; but, as of this past year, we've got a tenth. Or do we?

MIKE BROWN: This will absolutely rewrite the "History of Astronomy" textbooks. There is now a tenth planet out there.

ROBERT KRULWICH: When Mike Brown and his team at Caltech announced they'd discovered what looked like a new planet, they did not give it a name. Names are bestowed by an international commission of scientists. So, in the meantime, since they were looking at this little bright light for more than year, they gave it a nickname.

MIKE BROWN: It had no name at all, so we had to call it something, so when we talked to each other we'd know what we were talking about. So we always give things code names, nicknames, and this one we codenamed Xena.

ROBERT KRULWICH: From...?

MIKE BROWN: From, of course, the TV show, Xena, Warrior Princess.

Of course, Xena has a satellite, which we had no choice but to call Gabrielle, which is Xena's sidekick in the TV show.

ROBERT KRULWICH: No choice?

MIKE BROWN: No choice.

ROBERT KRULWICH: But in proper scientific circles, when scientists talk about this object they use...

MIKE BROWN: ...the very unwieldy 2003UB313.

ROBERT KRULWICH: And it will stay 2003UB313 until the International Astronomical Union officially decides that this is, indeed, a planet—which by the way, they have not done. They're not even close.

MIKE BROWN: We're in committee limbo, international committee limbo, which is about the worst possible place you could imagine being.

ROBERT KRULWICH: But what exactly is the problem? It looks like a planet. I mean, it's round; planets are round.

MIKE BROWN: Nothing's really round. The Earth has got a bulge in it, and Saturn is actually quite squashed.

ROBERT KRULWICH: Okay, but Xena's round enough; and it's got a moon, which is very planet like; and it orbits the sun. But it turns out, this matter is still debatable because there's no precise scientific definition for "planet," and there hasn't been one for a long time.

NEIL deGRASSE TYSON: Did you know that in 1801 a new planet was discovered orbiting between Mars and Jupiter?

ROBERT KRULWICH: Neil deGrasse Tyson is director of New York's Hayden Planetarium.

NEIL deGRASSE TYSON: They called it Ceres. And they looked some more, and they found another planet, and another and another. The count of planets in the early 1800s was greater than it is today, thirteen planets in the solar system. And they kept looking, and the numbers kept growing. And they were running out of names, and they realized that, rather than counting new planets, they had discovered a new swath of real estate in the solar system called the asteroid belt.

ROBERT KRULWICH: So Ceres became an unplanet, and was re-designated to a new class. And it became the biggest asteroid.

NEIL deGRASSE TYSON: So we've been there before. We know how to demote something.

ROBERT KRULWICH: And that's exactly what he did to Pluto. When the Hayden Planetarium reopened in the year 2000, Neil Tyson decided to de-planetize Pluto. "In our opinion," he said, "Pluto is now an icy object that's different from the other planets."

NEIL deGRASSE TYSON: It's got enough ice, so that if you were to take Pluto and transport it to where Earth is right now, the heat from the Sun would evaporate the ice and it would grow a tail. And that's just no kind of behavior for a planet. We have words for things with tails, they're called comets.

ROBERT KRULWICH: Same for Xena, another icy body that lives in the Kuiper Belt out beyond Neptune. But a lot of people simply ignored Neil Tyson and the Hayden Planetarium and stuck with the list they'd learned in school. Remember those planets in the right order? Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto.

NEIL deGRASSE TYSON: My very educated mother just served us nine pizzas.

MIKE BROWN: Martha visits every, Martha visits every Monday—must be for Mars—and just stays until noon, period. So there are two stupid things there. There's an "and" which is dumb, except the "and" is right where the asteroid belt is. I don't know if that's an accident or not. And then, I remember at the time, being in third grade, thinking that there's something funny about Pluto if it's really just a period at the end of a sentence.

ROBERT KRULWICH: Sophisticated scientists and ordinary folks can't seem to get together on this one. And Mike Brown, even though he discovered what could be the tenth planet, has this advice for the scientists:

MIKE BROWN: What I favor is the "give up" approach, which is to say, the word planet is not scientific, and it doesn't need to be. And as astronomers, we just need to get over it.

NEIL deGRASSE TYSON: These are the Pluto files, okay? This is hate mail that I've gotten from elementary school children. Handwritten letters saying, "Please, Dr. Tyson, what are you doing with Pluto? What? That's our favorite planet!"

"You are missing Pluto. Please make a model of it. This is what it looks like. It is a planet. Turn to the other page. A picture of Pluto."

"Dear Dr. Tyson, I think that Pluto is a planet for a lot of reasons, but you treat it like nothing! So if you can, please leave it a planet. And if you don't, then I say it is. And have a good day."

TWIN PRIME CONJECTURE

ROBERT KRULWICH: Our next story concerns prime numbers. It's a mystery that's been around for 2,300 years, since the days of the great mathematician Euclid.

Now a prime number, for those of you who have forgotten, is a number which can only be divided by itself and one. And there is this curious thing about primes. They seem for some reason to clump together. So if you start with 5, you'll notice that 5 is very close to 7. And then the next prime's 11 right next to 13, and then 17 very close to 19. And Euclid wondered, well do they just go on like this clumping and clumping forever? No matter how high you count?

Well, a mathematician has just given us an answer. And we thought the answer so intriguing that it was worth a song. So here it is, "Euclid's Twin Prime Conjecture" performed by our singing reporter, Rob Morsberger, for an audience of mathematicians.

ROBERT MORSBERGER (Singing):

Prime is the number
That is only divisible by itself and one.
They have no other factors,
Though they may have their detractors.
They are kind of fun.

MEL NATHANSON:

They have no detractors, everyone loves a prime.

ROBERT MORSBERGER(Singing):

'Cause they like to come in pairs,
with a number in between.
Just like 5 skip 7, 41 skip 43.
The name of our lecture, is "The Twin Prime Conjecture."
Primes will pair into infinity.

MAN:

11 skip 13.

KEVIN O'BYRANT:

17 skip 19.

ROBERT MORSBERGER (Singing):

Empirically we know,
This pattern reappears, however high we count.
Will it keep on skipping just like this?
Or somewhere down the line
Will it peter out?

TOM MORGAN:

No, we think it's going to go on forever, but no one knows.

ROBERT MORSBERGER (Singing):

Euclid first proposed this around 300 B.C.,
But none's ever proved it, in all of history.
Well this year Daniel Goldston, from the U of San Jose,
Says the pattern will continue,
In this skippy kind of way.

MEL NATHANSON:

His results certainly suggest it.

ROBERT MORSBERGER:

Goldston didn't prove the conjecture.

CARLOS MORENO:

But it's a major advance.

ROBERT MORSBERGER:

A major advance. He did show that primes appear close together.

KEVIN O'BYRANT:

Kind of big skips.

GREG CHUDNOVSKY:

Gaps.

ROBERT MORSBERGER (Singing):

Gaps! A big step in the right direction.
They like to come in pairs, with a number in between.
11 skip 13, 101 skip 103.
The name of our lecture,
Is "The Twin Prime Conjecture."
Primes will pair into infinity.

IVORY-BILLED WOODPECKER

ROBERT KRULWICH: Once upon a time there was a woodpecker, a big beautiful one; that lived in the woods in the American south. But as people crowded in and the forests got smaller, this Ivory-billed Woodpecker began to disappear. The last firm sighting was in 1944, and after that, it became a kind of ghost. People who love birds and love watching birds, insisted, "It's still out there. It's alive. It's wild. It's surviving." But when they looked, and a lot of them looked, there was no proof. And then recently, as you may have heard, something happened, maybe. Reporter Carla Wohl picks up the story.

CARLA WOHL: It happened here in Arkansas' Big Woods, a swamp that's been described as "America's Amazon."

TIM GALLAGHER (Cornell Laboratory of Ornithology): It suddenly burst out in front of us and flew across the bayou into the light. And then we both yelled, "Ivory bill!"

MELANIE DRISCOLL (Cornell Laboratory of Ornithology): When I first saw the bird, even though it was at a distance and it was naked-eye, I thought, "Oh my God, that's it!"

CARLA WOHL: Eyewitness sightings of the Ivory-billed Woodpecker—the Lord God bird, as people used to call it—old black and white footage doesn't do it justice. It was spectacular, with a call no serious bird watcher could resist.

When University of Arkansas at Little Rock professor David Luneau heard that the woodpecker had been spotted in the swamp, he grabbed his video camera...

DAVID LUNEAU (University of Arkansas at Little Rock): I keep mine running the whole time.

CARLA WOHL: ...and joined the search party.

DAVID LUNEAU: All aboard?

CARLA WOHL: All aboard.

DAVID LUNEAU: It's probably closing in on 1,000 hours.

CARLA WOHL: A thousand hours looking and listening for the Ivory bill.

DAVID LUNEAU: I heard a woodpecker tapping over there but he stopped.

CARLA WOHL: He searches from dawn to dusk.

DAVID LUNEAU: Woodcock, yeah, oh cool.

CARLA WOHL: "Eighty percent of bird watching," he will tell you, "is listening."

DAVID LUNEAU: Pileated woodpecker—we've heard...that's our third one we've heard today, and we haven't seen one yet.

CARLA WOHL: One day in April of 2004, Luneau was puttering along, his video camera propped up in the canoe.

DAVID LUNEAU: I just left it running. I had it recording like I always do when I come out.

CARLA WOHL: And this is what the camera saw: a good shot of his brother-in-law in the front of the boat, and there, just above the paddle handle, some movement. Even when you zoom in, it's fuzzy, a flash of white. The amount of white you see there is going to be very important.

DAVID LUNEAU: I said, "Did you see that? Did you see that? Did you see the white on that bird?"

CARLA WOHL: When he got home, he downloaded the video to a computer and examined it frame by frame.

DAVID LUNEAU: And you see a flash of white?

CARLA WOHL: Right.

DAVID LUNEAU: That's the back of the bird as the wing is starting to unfold.

CARLA WOHL: He came to believe the bird was the Ivory-billed Woodpecker, though at first he wasn't sure.

Kind of blurry.

DAVID LUNEAU: Yeah, not "kind of blurry." Go ahead.

CARLA WOHL: Blurry!

DAVID LUNEAU: It's blurry.

CARLA WOHL: Blurry or not, this scrap of video is the only hard visual evidence in a controversy over whether or not the Ivory bill has come back from the dead.

JOHN FITZPATRICK (Cornell Laboratory of Ornithology): It's a woodpecker with exactly the color pattern of an Ivory bill Woodpecker.

CARLA WOHL: John Fitzpatrick, the head of Cornell's respected lab of ornithology, is unequivocal.

JOHN FITZPATRICK: Absolutely. The Ivory bill has broadly white throughout. So here's a bird with white in its back and broad white on the back end of its wings. It could only be an Ivory bill.

JEROME JACKSON (Florida Gulf Coast University): The video is clearly not an Ivory bill.

CARLA WOHL: Jerome Jackson, an ornithologist at Florida Gulf Coast University, is not convinced.

JEROME JACKSON: "Found! Cornell Lab of Ornithology, Ivory bill Woodpecker!" I think there should be a question mark there instead of an exclamation point.

CARLA WOHL: Jackson has studied woodpeckers for 40 years. He says the bird on the video is the Pileated woodpecker, the Ivory bills' smaller cousin, still abundant in the Arkansas woods.

JEROME JACKSON: I think I'm looking at a Pileated woodpecker in flight. And looking at the backside of the birds wings...as a Pileated is flying, its wings are held back like this, and so the white is in a different position then you would normally see on the Pileated woodpecker. It's holding its wings as if it were paddles, paddling though the air.

JOHN FITZPATRICK: We're not looking at the underside of a wing here, we're looking at the upper side of a wing. From above, we see this huge white patch along the back end of the wing of an Ivory bill, and we see just a little bit of white on a Pileated, with a jet black back.

CARLA WOHL: Fitzpatrick backs up his argument with audio evidence. They have set up microphones in the woods and in 17,000 hours of recordings have something that sounds like the Ivory bill's call.

RUSS CHARIF (Cornell Laboratory of Ornithology): It's sort of a, "eh-eh-eh."

CARLA WOHL: Russ Charif is one of Cornell's audio experts. He plays the only known recording of the bird, made in 1935.

[Bird call]

RUSS CHARIF: And now, a portion of a recording that we made on January 29th, 2005.

[Bird call]

CARLA WOHL: Jackson still is not convinced.

JEROME JACKSON: Those recordings are not definitive of Ivory bill; they could possibly...could be a blue jay.

CARLA WOHL: Possibly, says Charif, but the last note of their calls is different. Again, here's the one Charif says may be the Ivory bill.

[Bird call]

RUSS CHARIF: So you can see there's one, two, three. And then this fourth one is a little bit lower.

CARLA WOHL: And now a blue jay:

RUSS CHARIF: All at the same frequency.

[Bird call]

CARLA WOHL: Still, Charif admits the audio is not conclusive. What they really need to prove the Ivory bill is alive, is a good clear picture.

DAVID LUNEAU: This looks like as good as spot as any, I guess.

CARLA WOHL: And so Luneau is placing motion-detecting cameras in promising places...

DAVID LUNEAU: A total, now, of 10 cameras.

CARLA WOHL: ...hoping to capture a snapshot of the Ivory bill. In the 623 photos taken so far, there are some pretty good pictures of the Pileated woodpecker, but not the elusive...

DAVID LUNEAU: ...but not the elusive Ivory bill.

JEROME JACKSON: What we have is a good hypothesis that Ivory-billed Woodpeckers might be out there. They've given us hope, and I like that hope. I would like to think that they have survived...

DAVID LUNEAU: I mean, it's got woodpecker chisel marks as opposed to...

JEROME JACKSON: ...and that we might have a chance to bring them back.

DAVID LUNEAU: We share some sort of collective guilt about having destroyed the habitat that took this bird out and a lot of other creatures to the brink of extinction. And we've got a chance to keep the species going. We've got another chance here.

PANDEMIC FLU

ROBERT KRULWICH: So not only did a woodpecker make news last year, birds themselves were a big item, very big: the subject of international summits, White House conferences. I'm talking, of course, about bird flu. And very particularly, I'm talking about something that probably hasn't happened yet, but could. And that raises a question.

So far, this new bird flu has not acquired the ability to travel on a cough or a sneeze, through the air, from one infected person to another. But what everybody wants to know is, could it learn how? And what are the odds?

Well, if you look at a virus, any virus, you'll find a recipe, a genetic recipe, a lot of instructions spelled out in chemicals, abbreviated A, C, G and U. Everything a virus knows comes from these instructions. So somewhere in the human virus there's an instruction that says, "When you infect a person, infect him here in the upper respiratory tract—not in the lungs, not in the tummy—just up here, and make the person, the host cough." 'Cause what gets the virus out, it's the way the virus transmits.

It's different in a bird. In a bird flu, the bird virus has an instruction that says "Infect the gut, and give the bird diarrhea, so it leaves droppings." And mostly it's the droppings that transmit the virus for birds.

So we do it here, they do it there. The bird virus, therefore does not need an instruction for coughing and sneezing.

But here's the bad news: back in 1918 or so, bird flu somehow acquired the gene for coughing and sneezing. It wasn't much use, it just sat there in birds. But when that virus got into people, that bird flu—because it could pass through the air—that flu killed 50 million people. So you may ask, "Well, in 1918, how did that happen?"

KANTA SUBBARAO: The 1918 viruses have acquired the necessary characteristics to infect people and transmit efficiently.

ROBERT KRULWICH: By accident?

KANTA SUBBARAO: Un-huh.

ROBERT KRULWICH: According to Kanta Subbarao, one of the nation's leading flu investigators, the 1918 bird flu got its cough and sneeze transmissibility by mistake. It was a random event that happened kind of like this: are you familiar with the old saw that if you put an infinite number of monkeys in front of an infinite number of typewriters, you would eventually get Hamlet?

KANTA SUBBARAO: I haven't heard that.

ROBERT KRULWICH: Okay, well let me explain it a bit. Imagine one monkey hitting a typewriter at random; he doesn't know what he's typing. But now, let's make it an infinite number of monkeys. And infinite is a whole lot of monkeys, so many that, eventually, some monkey somewhere is going to, completely at random, produce a perfect copy of Hamlet.

Well, in a similar manner, when one bird gets sick with bird flu, as it gets sick, inside the bird the virus is spreading, copying itself over and over and over, maybe a hundred million times. And if you've got a lot of birds, like this crowd here, that means in all these animals, altogether there could be 10 trillion viruses. So if you're asking, "What are the chances of a bird flu accidentally creating the ability to travel on a cough or a sneeze?" Well, it's kind of like the monkeys and the typewriters.

If you're looking at 10 trillion viruses and all you need is one mistake, just one, that spells out the right recipe, that could happen. I mean, you've got 10 trillion chances.

But here's the big surprise. When I said to Dr. Subbarao, "When we look at a human virus, do we know where in this sea of letters...would you know where this cough and sneeze ability is?"

KANTA SUBBARAO: Unfortunately not.

ROBERT KRULWICH: Hasn't it occurred to people to try and figure it out?

KANTA SUBBARAO: But it's a difficult thing to do.

ROBERT KRULWICH: So scientists don't know if the recipe is a few letters long— very simple—or if it's thousands of letters long and very complicated.

KANTA SUBBARAO: Nobody's sure yet.

ROBERT KRULWICH: What you don't know is a lot.

KANTA SUBBARAO: That's true.

ROBERT KRULWICH: Since we don't know the recipe, the genetic recipe, for coughing and sneezing, we can't figure the odds. Try it yourself.

Let's say this guy's chickens are all sick with bird flu, and he's got, let's see, one, two, three, four, five chickens, which means...so he's sitting next to 500 million bird flu viruses. And I ask you, "What are the chances there's a cough and sneeze virus right here ready to infect him?"

Well, if the recipe for coughing and sneezing is 13 letters long, if it's very simple, and there are 500 million viruses in his chickens? Seems likely, kind of like just one of these monkeys accidentally typing a little bit of Shakespeare, sure. But if the recipe for coughing and sneezing is 13,000 letters long, in a very precise order, that's like one monkey accidentally typing the first two acts of Hamlet perfectly. Those are very different odds.

So if we don't know the recipe, we really can't know the odds. And remember, even if this chicken, or it could be a duck or a goose, has randomly created the cough and sneeze virus, that virus still somehow has to get from this bird to this man.

KANTA SUBBARAO: That's right. That's right. So there is, there are all these events that probability...has to sort of all come together: the, the, the chance of the mutations and exposure to a susceptible host.

ROBERT KRULWICH: This seems like such long odds to me: got to have the sick duck, the sick duck has to be near a person who's vulnerable, the person has to suck in the virus, the virus has to attach. And yet it happened. It may sound wildly improbable, but in 1918, it did happen, so there is a danger.

But since we don't know the recipe for coughing and sneezing, when you read stories that seem to know the odds, that say the bird flu "is coming," or the worldwide pandemic is "inevitable," or it's "overdue," or "around the corner," be skeptical. We know this flu is dangerous to birds. We don't know if it'll be dangerous to humans tomorrow, or next year, or decades from now. We just don't know.

LAB MEAT?

Ummm, meat—this is a story about meat. Some people avoid meat because it involves killing animals. Other people love meat. They can't get enough. Here is a development that might make both sides happy. Reporter Win Rosenfeld has the story.

DANIEL NEWMARK: I like meat. I eat it all the time.

JAY GONZALES: Pork chops, steaks...

MAYE MUSK: I love hamburger.

WIN ROSENFELD (Correspondent): You might not have thought about it, but that hamburger that he's about to put in his mouth, it's inefficient to produce.

BOB LILIENFELD (Author): ...because of all the water, grains, chemicals, fertilizers, everything it took to turn grass into cows and cows into meat, and get the meat to your house.

WIN ROSENFELD: That's a lot of energy and a lot of waste. And meat can make us sick, and we do have to kill billions of animals. Jason Matheny of the University of Maryland says he's got the answer.

JASON MATHENY (University of Maryland): What we're doing here is cloning, effectively, the muscle cells from the farm animal.

WIN ROSENFELD: Cloning meat?

JASON MATHENY: That's right.

WIN ROSENFELD: Who's going to eat that?

HARRY BIXLER: As long as it wasn't poisonous, I'd give it a try.

CATHERINE CARABALLO: If I can't tell the difference, of course I'd eat it.

MONIQUE CHANG: As long as it tastes the same.

JASON MATHENY: If you start out a chicken cell, it should taste like chicken.

WIN ROSENFELD: Then again, doesn't everything. How about texture?

JASON MATHENY: Farm animals produce meat of a certain texture because they move around. We have to mimic those conditions in vitro.

WIN ROSENFELD: In vitro meaning?

JASON MATHENY: Literally, stretch the cells mechanically.

WIN ROSENFELD: Exercise cells in a lab? Okay, so the only question left is...

CATHERINE CARABALLO: You got a piece?

WIN ROSENFELD: Here it is: cultured meat.

CROWD: Bon appetit, bon appetit.

WIN ROSENFELD: Now, this piece was made by scientists at the University of Western Australia. NASA's been interested, and the Dutch government has invested $5,000,000 dollars in cultured meat. Right now, you have to clone a cell, stretch it on a scaffold, and feed it an expensive, nutritious soup. This makes each little bit very costly. What if I wanted a little more?

JASON MATHENY: If you wanted to pay a million dollars, right now, we could get you a kilogram of beef.

WIN ROSENFELD: No thanks, I'll stick with this, for now.

STEM CELLS UPDATE

ROBERT KRULWICH: One of the most controversial science stories of the year involves stem cells, cells that may one day cure terrible diseases. But the problem with stem cells is they often come from embryos, thus the phrase "embryonic stem cells." And embryos, while they start no bigger than a grain of sand, can become babies, so there is a moral issue here.

But what if—and we're just going to think out loud—what if you could make an embryonic stem cell without creating an embryo? Could you? Should you? Well, we know someone who's trying. Reporter Julia Cort has the story.

JULIA CORT (Correspondent): As he winds through the labs of M.I.T., Alex Meissner is trying to sidestep an ethical minefield. He hopes the tiny cells that float in his Petri dish might hold the key to solving one of the biggest controversies facing science: whether it's ethical to use cells from human embryos in medical research.

RUDOLF JAENISCH: I believe this research has enormous potential. And it will revolutionize medicine in the years to come.

THOMAS BERG: I don't want to live in a world, I don't think anyone wants to live in a world, where we're destroying embryos...we're creating them and destroying them in mass quantities for research purposes.

JULIA CORT: While experts debated here, halfway around the world, South Korea seemed to be forging ahead. Last August, they claimed a spectacular first, a cloned dog.

But since then, the Korean king of clones, Hwang Woo-Suk, has been dethroned, accused of fabricating his results, including groundbreaking work cloning human embryonic stem cells. The Korean fiasco has cast a cloud over the field, but U.S. researchers still want to move forward, believing embryonic stem cells hold great potential for medicine, since they can become any kind of cell in the human body. But because they come from early human embryos, funding for the research is extremely limited.

GEORGE DALEY (Harvard Stem Cell Institute): Unfortunately, here in the United States, even though we're chomping at the bit to do the work, the kind of funding restrictions that we're under, the kind of presidential policy that we're under, is really the hindrance.

JULIA CORT: Physician and researcher George Daley is eager to create stem cells that are an exact match to sick patients. To do that, he wants to try cloning technology, but so far, the only cloned cells he's made belong to mice.

GEORGE DALEY: We're essentially frozen in time, at 2001, while the rest of the world has moved forward very, very aggressively.

JULIA CORT: The controversial cloning process would work like this: take an egg from a woman's ovary, remove its genes or DNA, then, get a cell—like a skin cell—from a patient, and put its DNA into the egg. The egg is stimulated to divide, as if it had been fertilized. After a few days, the early embryo has 50 to 200 cells.

The goal is to turn some of these into embryonic stem cells that would be a perfect genetic match to a sick patient. But because the cloned embryo would be destroyed in the process, critics say this research is wrong. With the destruction of human embryos at the center of the debate, a few scientists approached the new year asking if it might be possible to make both sides happy. What if they could find a way to create embryonic stem cells without destroying any embryos?

WILLIAM HURLBUT (Stanford University): I think it should be doable.

JULIA CORT: Physician and ethicist William Hurlbut thinks the solution may lie in tinkering with the cloning process.

WILLIAM HURLBUT: There's a way to get the cells without creating embryos. We just have to have the constructive conversation to find the way.

JULIA CORT: The challenge intrigued M.I.T.'s Rudolf Jaenisch, a leading expert on stem cells and cloning. With the help of graduate student Alex Meissner, Jaenisch tried to create something that would yield stem cells, but was not an embryo at all.

RUDOLF JAENISCH: What is an embryo? What's important? I think an important part of the sense of an embryo is the potential to develop, to organize itself.

JULIA CORT: The Jaenisch team set out to eliminate that potential. First, they took a tiny bit of skin from a mouse's tail and let it grow in culture. With the skin cells growing in a Petri dish, Meissner concocted a special virus and added it to the skin cells. The virus went to work and inserted an extra bit of DNA into the skin cell DNA. Meissner performed the cloning, sucking up a skin cell now containing the extra DNA and transferring it into a mouse egg. And then the team waited and watched. Jaenisch's hope was that the extra bit of DNA they'd added would shut down one key gene, a gene that's crucial for organizing the early mouse embryo and triggering the construction of the placenta.

RUDOLF JAENISCH: The placenta, of course, is very important in signaling the fetus to develop. Without the placenta, it cannot. And the experiment worked very straightforward. It was actually surprisingly simple to us.

JULIA CORT: With that key gene turned off, the unorganized cluster of cells did not develop normally, and, Jaenisch says, would never become a baby mouse. But it could be turned into useful stem cells.

RUDOLF JAENISCH: The real question is, does it solve the ethical problem? Some people said yes, others said, "No. It's a particularly devious way to murder an embryo." I would argue, from the biological point of view, it is not an embryo. It doesn't qualify to be called this. It doesn't have any potential whatsoever to ever organize itself to a fetus.

JULIA CORT: Father Thomas Berg is encouraged by Jaenisch's experiment.

THOMAS BERG: I think the jury's still out as to whether it's an embryo or not. But I think it's incredibly interesting, from a moral standpoint, from a scientific standpoint, obviously. I think what Rudy Jaenisch did holds out some hope that those of us who do not want to live with a future of embryo-destructive research, we might have a way out.

JULIA CORT: But so far, there is no consensus about the moral status of what Jaenisch created among stem cell opponents or supporters.

ARTHUR CAPLAN (University of Pennsylvania School of Medicine): The scientists who play along, I think, are playing the wrong card. They think, "Yeah, maybe if I'm clever enough I'll satisfy all the critics." I think the critics are not going to be satisfied. I think they don't want to see embryonic stem cell research happen, and I don't think they want to see anything involving cloning happen.

JULIA CORT: Ethical objections have slowed U.S. research. Few labs have tried to use cloning to make human stem cells, and none have succeeded. The Korean scandal means that the technique for humans is unproven. But that, for many U.S. researchers, is all the more reason to keep moving ahead.

GEORGE DALEY: I have patients, and I can see a way to apply this technology to study their disease and perhaps treat their disease. I want to be able to use that process today.

ARTHUR CAPLAN: If we get diverted into the debate about, "Can we make a pseudo embryo or an embryo-like thing?," you could spend the next five, 10 years trying to figure out how to tweak an egg or play with embryos. I think, to spend too much time trying to respond to every possible critic is a recipe for paralysis, not for breakthroughs.

ROBERT KRULWICH: Around the corner, around the world, more science stories in the news. Hamburg, Germany: toads are exploding at an alarming rate—1,000 believed dead. And why? Maybe they were bitten and infected by crows, but, says German scientist Heidi Meyerhofer, "Nein!"

HEIDI MEYERHOFER (Translation from German): I have been working here for 15 years and have never experienced a problem this big with amphibians. Experts could give no advice about the symptoms.

ROBERT KRULWICH: In short, scientists haven't the froggiest idea.

Meanwhile, back in the U.S.A. —if you drive, put down the cell phone because researchers discovered this past year that a normal 30-year-old driver speaking on a cellular telephone has the reaction time of a 70- or 80-year-old. Oh dear! Phones and driving prove a deadly mixture. And that's no phony baloney.

STRONGER HURRICANES

After Hurricane Katrina a lot of folks were thinking about our planet and were asking, "Are killer storms on Earth becoming more frequent? And if they are, why?" We've always known that hurricanes on our planet come in cycles, but reporter Chad Cohen looked back at the past season and wondered if maybe there's something else going on here.

CHAD COHEN (Correspondent): You're looking into the eye of the most intense Atlantic storm ever measured. It's not Katrina, the hurricane that devastated New Orleans. It's Wilma, the third Category 5 storm to form in the Atlantic in the 2005 season. Wilma set a new record, suggesting that more intense hurricanes may be in store.

And if there's a reason why, it's out here. Research ships like this one, run by N.O.A.A., take the ocean's temperature every three hours, 24 hours a day. As the crew reels in this elaborate probe, they bring back evidence that the oceans are heating up.

These numbers have presented us with one inescapable fact, the surface temperatures of the world's oceans has gone up a half degree Celsius in just the last 35 years. And there's nothing hurricanes like more than warm water. The more warm seawater a storm can churn into vapor, the more heat is released into the upper atmosphere. That lowers the pressure and causes winds at the ocean surface to spiral inward and pick up speed. And some scientists, like M.I.T. atmospherics professor Kerry Emanuel, believe that the rise in ocean temperatures is the result of global warming, the heating of the Earth caused by human activity.

Can we say for sure that we're causing that warming?

KERRY EMANUEL (Massachusetts Institute of Technology): The last few decades, the temperature has gone up so quickly and so far out of what we've seen in the last thousand years or so, that virtually everybody in the business now believes we're seeing a manmade signal in the global temperatures.

CHAD COHEN: And we know that hurricanes like warm water. So it's very easy to just kind of say, "There it is. We're causing hurricanes."

KERRY EMANUEL: We can't say we're causing more hurricanes.

CHAD COHEN: We can't say we're causing more hurricanes, because the total number of hurricanes worldwide hasn't changed at all. For reasons no one can explain, it always seems to hover right around 90 per year. So if global warming hasn't caused more hurricanes, has it made them stronger?

To find out, Kerry Emanuel took advantage of five decades worth of data collected by aircraft flying directly into the paths of hurricanes. He concluded that over this time, the average strength and duration of hurricanes in the tropical regions of both the Atlantic and Pacific oceans has doubled. But even more sobering is how closely this increase in storm power matches the rise in ocean temperature.

It's pretty striking, actually. You look at the graph and the sea surface temperatures go up like this, and the intensity of hurricanes goes up, it follows perfectly.

KERRY EMANUEL: Yes, that's right. I think you can say, fairly unequivocally, that half a degree rise in ocean temperature will cause hurricanes to be more intense.

PETER WEBSTER (Georgia Institute of Technology): This is the equator, here.

CHAD COHEN: At Georgia Tech, Peter Webster examined a completely different set of hurricane measurements, 30 years of global satellite observations. His conclusions mirror those of Kerry Emanuel's.

PETER WEBSTER: We find a consistency between the increase of surface temperature in all of the oceans and a change in intensity to more intense storms.

CHAD COHEN: But while both scientists agree that warmer oceans have contributed to more intense storms, they caution that formation of hurricanes is complex, to say the least, and involves many other factors, including just plain chance.

KERRY EMANUEL: Hurricanes are like any phenomenon in the atmosphere, creatures of chance. If you're interested in any given storm, it is the roll of the die. And the whole question is whether that die is weighted.

CHAD COHEN: The problem with hurricanes is that we can never say for sure what exactly happens. There's always an element of chance. So we take the temperature of the water, measure the amount of moisture in the atmosphere, we look at what the winds are doing, and depending on how all those factors come together, we get a probability that a hurricane will become either a Category 1, a 2, a Category 3, 4 or 5.

KERRY EMANUEL: I think there's little doubt that we are loading the die. We're causing global warming. The tropical temperatures are going up.

CHAD COHEN: But whether global warming is having an impact on hurricanes, well, not every scientist agrees, even those on the front lines of storm forecasting.

CHRIS LANDSEA (National Hurricane Center): A hurricane was predicted to come ashore.

CHAD COHEN: Last October, as Hurricane Wilma was poised to hit Florida, Chris Landsea, at the National Hurricane Center in Miami, helped track the powerful storm.

CHRIS LANDSEA: There's distinct cycles of hurricane activity in the Atlantic, that it tends to go 25 or 40 years very busy, and 25 to 40 years fairly quiet.

KERRY EMANUEL: If all we had to go on was the hurricane data, I don't think we would be terribly alarmed. We'd just say, well, there...you know, it's been changing the last 25, 30 years, so what? It's the correlation with sea surface temperature and the fact that that trend is unprecedented for a long time that has us worried.

CHRIS LANDSEA: We're not seeing unprecedented. We're seeing the same type of hurricane activity that we saw in the middle part of the 20th century. And it actually may have been busier back then, than it is now.

KERRY EMANUEL: A lot of things in science, sometimes there isn't a smoking gun. There isn't one piece of evidence that everybody looks at and says, "Yeah, you know, that proves that global warming is affecting hurricanes." What you have are multiple pieces of evidence which all point in the same direction.

CHAD COHEN: This high stakes debate will only be resolved with more data, and that won't be a problem. Hurricane season is never too far away.

PROFILE: TYLER CURIEL

ROBERT KRULWICH: For a whole lot of reasons—meteorological, political, engineering reasons—Hurricane Katrina was a major, major science story last year.

But now, we're going to add one more reason. We're going to tell you a Katrina story about a young man who got very sick, but he had one bit of luck. He had a very unusual friend, Dr. Tyler Curiel. Hold on a second, he's a hard man to keep up with. He runs 100 mile marathons. This is a man who's on his very own path; he goes where he wants to go.

Now he's the Chief of Hematology and Medical Oncology at Tulane University where he runs a lab that specializes in immune cells.

TYLER CURIEL (Tulane University School of Medicine): We look at the human immune response to cancers and to infections.

ROBERT KRULWICH: But Tyler had never seen anything or anyone like Andy Martin. In 2000, Andy Martin, from California, was just about to start medical school at Tulane.

ANDY MARTIN : A week before I started my first year, it showed up. I was on a vacation, like a last hurrah vacation, and I started getting nosebleeds.

ROBERT KRULWICH: Andy was diagnosed with a very rare and very deadly cancer, called S.N.U.C.

TYLER CURIEL: S.N.U.C. is Sino Nasal Undifferentiated Carcinoma. Andy decided that he wanted to do research on his own cancer. He persuaded me to allow us to biopsy his tumor.

ROBERT KRULWICH: Andy said...

AVRIL JENSEN (Andy Martin's sister): "If this cancer's going to get me, damn it, I'm going to go down fighting, you know, and make a difference, so that future people who are diagnosed with this don't have the same outcome that I had."

ROBERT KRULWICH: The student and his mentor worked side by side to try to find a treatment, even though both of them knew that Andy didn't have much time.

AVRIL JENSEN: Tyler and him had a really good friendship, as well as, you know, this amazing medical experience together.

RUTH BERGGREN (Tyler Curiel's wife): Andy came over to our house for dinner many times. He enjoyed wine-tasting; particularly he was fond of ports.

ROBERT KRULWICH: When Andy was about to undergo chemotherapy and lose his taste, Tyler, a bit of a connoisseur, threw a wine-tasting party. And Andy's classmates shaved their heads in solidarity. Andy is the bald guy in the middle.

And the doctor raised money for his student's research by breaking a world's record: he dribbled a basketball for 24 hours, while running a total of 108 miles.

AVRIL JENSEN: He's crazy.

ROBERT KRULWICH: They generated a living cell line from Andy's tumor, the only known cell line of S.N.U.C. in the world. And those cells outlived Andy. Already very sick, Andy Martin left home to visit friends at Tulane when he was overcome by cancer, in November, 2004.

AVRIL JENSEN: When it came to that week, Tyler kind of took over as his personal physician. And he was there every day at least one time, sometimes more. He, he passed away on a Friday night in New Orleans.

ROBERT KRULWICH: And when Hurricane Katrina struck at the heart of New Orleans, Tulane University was right in its path. People, homes and property were in serious danger and so was a lot of science. Tyler decided to stay in his lab through the storm.

He was joined by his colleague and his neighbor at the lab, Mike Brumlik. Together, they were determined to protect the millions of dollars of equipment there, and the research and Andy Martin's cells.

MIKE BRUMLIK (Tulane University School of Medicine): These cells were very important. There was...this was personal.

TYLER CURIEL: ...number one thing I knew we had to save was we had to get the Andy Martin S.N.U.C. cells out.

ROBERT KRULWICH: Their plan was simple. Keep all of the samples dry and cold enough to survive just a brief loss of power. They spent the whole weekend hard at work.

TYLER CURIEL: We had consolidated all of our things into three or four freezers.

ROBERT KRULWICH: Monday morning, the storm brought winds stronger than 150 miles an hour.

TYLER CURIEL: It was like The Wizard of Oz. We'd look out the window and gigantic pieces of buildings would just go blowing by.

ROBERT KRULWICH: By the time the storm ended, their building was running on an emergency generator, but the samples were fine. Tyler went to the phone to tell friends everything was okay.

TYLER CURIEL: Mike Brumlik walked into my office—we're in Tulane Medical School, in my office—and he said, "You might want to look out the window."

MIKE BRUMLIK: And he does this. And, uh, of course, his jaw drops, because he realizes what...more or less what I realized, which is that we're in very deep trouble.

TYLER CURIEL: I looked out the window and saw that we were flooded. I had no idea. As far as our research goes, this is the worst-case scenario. It doesn't get any worse.

ROBERT KRULWICH: Suddenly, it's a race against time. The men try to move a 400-pound freezer down six stories, and across this pedway, to the building next door which has better emergency power.

It takes them all day to move the samples. And when they finally make it to the other building, the generator there is almost under water.

MIKE BRUMLIK: The generator is not in a safe place. Six more inches of water rising and the generator is toast, so we are effectively doomed at this point.

TYLER CURIEL: You don't want to be melodramatic, but I was thinking, this is my whole life's work, and it's melting.

MIKE BRUMLIK: And the power fails at about 5 p.m. on Tuesday. And that's it. The only place to save anything cold is the liquid nitrogen tanks.

ROBERT KRULWICH: The problem is liquid nitrogen will evaporate, which means the samples have maybe 10 days, and then they'll melt.

TYLER CURIEL: And you're looking around, the city's flooded, you're thinking, it's going to be months before we can come back in. We had no idea.

ROBERT KRULWICH: The next morning, after Tyler and Mike had packed everything they could into the liquid nitrogen, they get another surprise; this one comes in uniform.

TYLER CURIEL: You've got two minutes to get out and evacuate or you're going in handcuffs. It was...bang...and then, they've got big rifles on their back. And you don't argue with people like this. I couldn't find my shoes. And I kept telling them, I'm just looking for my shoes. And they said, "Buddy, you're going in the cuffs." We left our food behind, we left our water behind, and we were off.

ROBERT KRULWICH: Tyler was headed to Charity Hospital, where there were still hundreds of patients.

TYLER CURIEL: I had been there a few times and saw how desperate conditions were. Mike said, "If you're going to Charity, I'm going to Charity."

MIKE BRUMLIK: I had done everything I could do to protect the science. And now it was time to help people.

ROBERT KRULWICH: Tyler and Mike hopped into a canoe they had been keeping handy.

TYLER CURIEL: ...shove off and we'd paddle right out through that exit right there.

ROBERT KRULWICH: And then they paddled a couple of blocks down to Charity, where Tyler's wife, Ruth Berggren, was one of the doctors in charge.

RUTH BERGGREN: He said, "What can I do for you?" And I thought about it, and I said, "Honestly, I need you to go fetch water." So here's my brilliant husband, the scientist, the immunologist. He actually said to me, he said, "I'm a perfect person for this job."

ROBERT KRULWICH: By now, these guys had seen just about everything.

TYLER CURIEL: We had already been flooded in for four or five days. Food was low, water was low; we had been without electricity for a number of days. It was very hot. Conditions were terrible.

ROBERT KRULWICH: They had successfully evacuated the patients at Charity Hospital.

TYLER CURIEL: So I realized, you know, time's up. You have to go.

ROBERT KRULWICH: But remember, the clock was ticking. It had been three days since Tyler put his lab samples into the liquid nitrogen. He had a week, maybe less, to keep them from melting, including the cells of Andy Martin.

AVRIL JENSEN: It was scary. It was a very scary time. And my mom even said it's like Andy dying all over again.

ROBERT KRULWICH: From Dallas, Tyler worked the phones for almost a week. He got a jet, coolers. And now he and Mike raced back to New Orleans.

MIKE BRUMLIK: Now the lab smells bad because we have freezer stuff and fridge stuff that's perished, so it doesn't smell pretty. But preying on our mind is, "Did the nitrogen make it?"

TYLER CURIEL: And we had the three liquid nitrogen containers lined up, one, two, three. I turned to Mike. I said, "Mike, I'm going to lift the lid, and if it's warm in there and the samples are thawed, game's over." And he said, "Do it."

MIKE BRUMLIK: Together we lift the lid and this plume of, of, of vapor hits us in the face.

TYLER CURIEL: It was really cold. It was really white. That's what it's supposed to look like.

ROBERT KRULWICH: By chance, out of all the samples inside all three freezers, the first box that Tyler pulled out contained Andy Martin's cells, frozen, safe and sound.

AVRIL JENSEN: I was calling everybody. Oh, they made it out!

TYLER CURIEL: So we were high-fiving and just going, "Yeah!"

AVRIL JENSEN: One of the port wines that Andy liked, he actually had a bottle, and it's still at my parents' house. And Tyler had made some crack about celebrating, and I said, "Well, I have one of Andy's bottles of Fonseco, you know? I can ship it to you, wherever you want." He said, "No, I'd like if you would save that, and we can all celebrate together when we see each other again."

ROBERT KRULWICH: Andy's cells were saved, but Tyler lost a lot of research. And he's not alone.

TYLER CURIEL: My sense is that we've lost millions of dollars worth of research, thousands of man-hours of research. And then you multiply that times hundreds of investigators. And it's staggering.

ROBERT KRULWICH: But Tyler knows how to stay on his feet.

TYLER CURIEL (Turning car ignition on): How about that?

ROBERT KRULWICH: His home wasn't too damaged. And he had to shift his lab work to different cities for a while. But New Orleans is calling, and it won't be long before Tyler's whole operation is back up and running.

So that's our show. But NOVA scienceNOW continues 365 days a year on our podcast, in science cafes, on our Website at pbs.org. You can watch the broadcast again, if you like, online. And by the way, when you're there, drop us an e-mail and let us know what you think of our show, and what stories you'd like to see on future episodes of NOVA scienceNOW. So, from everybody here, I'm Robert Krulwich. Goodbye.

NOVA is a production of WGBH Boston.

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NOVA scienceNOW: January 10, 2006

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