Accessibility links

Our World — 30 June 2007


MUSIC: "Our World" theme

Straight ahead on "Our World" ... another step forward in stem cell research ... a Mars rover prepares for its next big adventure ... and a penguin so big, it might fit into YOUR dinner jacket.

CLARKE: "The bones of these fossils are so well preserved that when the team saw this skull, the first skull of a giant penguin, we were just taken aback.

Those stories, a radioactive threat facing some native American Indians, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

British and American scientists this week announced the discovery of a new kind of embryonic stem cell in mice that could help advance the research on stem cells in humans.

Embryonic stem cells, you'll recall, are unspecialized cells that have the potential to develop into any kind of cell in the body — bone, blood, brain or other vital organs. A lot of researchers think it may one day represent a whole new way of treating a wide range of diseases.

In the meantime, however, there's a lot to learn, and two research papers published this week in the journal Nature could help. Roger Pederson, co-author of one of the papers, explained to reporters in London the importance of the newly-discovered mouse stem cell.

PEDERSON: "This is a new type of embryonic stem cell that has very strikingly similar properties to human embryonic stem cells. This is very intriguing because it can provide a model for studying and accelerating studies of human embryonic stem cells, but we think it also tells us something about the actual origin, the biological origin, of human embryonic stem cells."

Pederson, now at the University of Cambridge, previously worked at the University of California. He moved to Britain in 2001 amid concerns over U.S. restrictions on federally-funded stem cell research. If embryonic stem cells from rodents can be used in place of their human counterparts, it could speed research in a very exciting field.

The discovery was made independently by scientists at Oxford University, including Richard Gardner, co-author of the other paper published in Nature. He said that the techniques they used could be used on other animals — primates, perhaps — to get an even better animal model for research purposes.

GARDNER: "What this tells us is, if you use different conditions, you can get pluripotential stem cells out of the mouse, so it's going to encourage people to go back and do the same on any other mammal, and therefore there is no reason why you shouldn't find a mammal that is much closer to the human in this regard than the mouse is."

Since embryonic stem cells can potentially become virtually any type of cell, they offer hope of curing disease from Alzheimer's to diabetes to many more. But any cures that might be developed are still years away as the research remains in the laboratory stage.

At a meeting this week on avian influenza, or bird flu, U.N. officials reported some progress in slowing its spread, but said that as long as the virus is out there, the risk of a human flu pandemic remains.

Efforts to monitor and contain the disease have achieved important results, they said, including a rapid reponse in places where the deadly H5N1 virus has recently been introduced. On the other hand, the Chief Veterinary Officer of the UN's Food and Agriculture Organization, Joseph Domenech, told reporters Wednesday that avian flu remains a danger in many places, and he cited Nigeria, Egypt and, especially, Indonesia.

DOMENECH: "There [are] a lot of outbreaks, a lot of shed of virus in the environment, and then contacts with humans [who] can get the disease, and this is what is happening. We have human cases. So Indonesia for sure, this is where the situation is of high risk of getting a new [mutated] virus and the origin of a human pandemic."

Of the 315 human cases of avian flu identified by the World Health Organization, about one-third have been in Indonesia.

The people at greatest risk now are those in close contact with birds, especially chickens — people who sell them, slaughter them or live near them.

So far, avian flu as been a disease that humans catch from birds. The fear is that a mutation will allow the virus to be spread easily from person to person, which could pave the way for a pandemic. That may or may not happen, but David Heyman (HAY-man) of the World Health Organization, says that in any case, preparing for a possible flu pandemic is a good idea.

HEYMAN: "There will be other pandemic threats, so the activities to prepare today for a pandemic will benefit all those other threats that are with us today and will continue with us in the future."

Experts at the U.N. meeting in Rome stressed the need for continued monitoring of avian flu cases and improved sanitary conditions, especially in poultry markets.

Officials at the U.S. space agency NASA Thursday gave the OK to drive the Mars rover Opportunity into a steep crater for a close-up look at rocks that could give scientists clues about the Martian environment billions of years ago.

Since September, Opportunity has been skirting around the top of the 800-meter wide Victoria crater, taking great pictures, but that's not the same as going down for a closer look. Victoria formed when an object like a meteorite slammed into the Martian surface maybe billions of years ago. The impact spread material called 'ejecta' around the crater, covering up what had been the surface. Principal investigator Steve Squyres said scientists think that former surface material is visible just under the rim of the crater.

SQUYRES: "So this material may be preserve in its details information about the interaction of these Martian rocks with the ancient Martian environment. And so we really seek to understand here how that formed, and whether or not it could reveal something about what the Martian environment was like back when the crater formed."

NASA officials admit there is some danger in sending the rover Opportunity into the crater, but they think the possible gains are worth the risk. In any event, Opportunity and the other rover, Sprit, are more than three years into their Mars exploration mission — a mission that was originally scheduled to last just three months.

Here in the U.S., school's out, which means it's summer vacation time. And you wouldn't believe how stressful it is to pack up the car for a trip to the beach, or elbow your way through airport security. Sometimes it seems taking time off is, well, a lot of work. Anyway, that's the way we tend to do it here. But as Rose Hoban reports, concepts of leisure vary among various cultures, even though we all like to relax.

HOBAN: People all around the world like to relax. But leisure means different things depending on where you are in the world, and takes on very different forms.

Psychologist Yoshi Iwasaki is a professor at Temple University in Philadelphia, Pennsylvania. He was born and raised in Japan, but he studied in the United States and Canada, where he became curious about how people from different cultures handle stress. He says one way is to recreate, to participate in leisure activities. Iwasaki says that means different things in different cultures:

IWASAKI: "In the United States, people value consumption, making money and consuming money, it's, I think, an American icon. People spend so much money on free time activities. It's summer time now so people try to create or engage in exotic vacation."

HOBAN: Iwasaki says in other parts of the world, people derive as much benefit from leisure time activities that don't require spending so much money.

IWASAKI: "People particularly in non-western areas of the world their leisure behavior is more holistic, meaning their leisure behavior is more integrated with in the people's daily lives. People do not separate leisure activities [from] work."

Iwasaki cites an example from more traditional cultures of the Middle East and in Asia, where childrearing and staying in the home is the norm for women. He says activities such as cooking together or minding children together can become a form of leisure:

IWASAKI: "These women creatively construct leisure space. They socialize, they engage in some form of games, it's very less costly activity. And this takes place in the home and the people value these social gatherings and in this case this is a leisure space particularly for women who have to cope."

HOBAN: In the end, Iwasaki says the quality and meaning of leisure activity is as important to enhancing the quality of life as the time and money spent doing it. His paper on leisure in different cultures is published in the latest issue of the journal Social Indicators Research. I'm Rose Hoban.

Time again for our Website of the Week, when we showcase interesting and innovative online destinations.

This week, it's the companion website to the print magazine Technology Review, a respected publication affiliated with the Massachusetts Institute of Technology, and featuring not just the contents of the magazine but a steady update of tech news.

PONTIN: "And by and large they analyze news about emerging technologies in areas we're interested in: nanotechnology, biotechnology and, of course, computers."

Jason Pontin is editor in chief of TechnologyReview.com. He says the site attracts up to 700,000 unique visitors a month, including a range of early adopters and technology professionals.

PONTIN: "What all our audience has in common, however, is a passionate belief that the most important influence upon a company, an organization, a nation-state or even a person's life can be technology."

TechnologyReview.com hosts several blogs, and users can leave comments, which often produce extensive conversations around the online articles.

Pontin says at TechnologyReview.com they focus on emerging technologies, rather than established technology on the one hand or pure science on the other.

PONTIN: "So we might talk about civil engineering technologies that Holland is using to prevent the worst excesses of global warming. Or we might talk about the most recent breakthroughs in artificial intelligence. I think what makes TechnologyReview.com a truly unique site is both the variety of stories that we cover, but also that the focus needs to be emerging and new."

To do a better job of telling the story, TechnologyReview.com is adding videos and a mobile version for phones and other handheld devices. Using technology to update you on the latest technology at TechnologyReview.com, or get the link from our site, voanews.com/ourworld.

MUSIC — Marketts: "Out of Limits"

You're listening to VOA's state-of-the-art science and technology magazine, Our World. I'm Art Chimes in Washington.

A short while back here on "Our World" we reported on Colony Collapse Disorder, the mysterious disappearance of honeybees from hives in North America and Europe. It's a worrisome problem for farmers, who depend on honeybees to pollinate many important crops.

The cause of Colony Collapse Disorder, or CCD, is still unclear. But whatever it is, the head of the American Beekeeping Federation, Daniel Weaver, says it could signal trouble for other pollinators.

WEAVER: "So we should care about CCD, not just because it's affecting honeybees, but because some of the things that could be causing CCD, like application of herbicides, fungicides and insecticides, could be having similar negative influences on all pollinators."

Weaver spoke in Congress this week, at a House of Representatives hearing on a proposed Pollinator Protection Act, which would fund research into Colony Collapse Disorder.

Bees aren't the only pollinators that are at risk. Because beekeeping is a business, the health of honeybee hives is carefully monitored. But Prof. May Berenbaum of the University of Illinois, who chaired a National Research Council panel on pollination, told members of the House Committee on Natural Resources that other pollinators may also be affected. Sometimes the health of entire ecosystems relies on the obscure pollinator of what Berenbaum calls a keystone species.

BERENBAUM: "Just as a keystone maintains the integrity of a stone arch, a keystone species maintains the integrity of an ecological community. Fig trees, for example, are keystone species in tropical communities. The fruits nourish toucans, parrots and pigeons, as well as bats and monkeys and even fish in nearby rivers. The foliage supports insects, including butterfly larvae. And the tree itself provides habitat for invertebrates, rodents, reptiles and amphibians. Most fig trees, however, owe their existence to one or two species of fig wasps, the only known pollinators that can negotiate the complex floral structure."

The role of natural pollinators is something most of us take for granted. This past week was designated National Pollinator Week by the U.S. Agriculture Department to remind us of the contribution they make. Another reminder: the U.S. Postal Service Friday issued a series of stamps that show butterflies, bees, bats and hummingbirds at work, pollinating wildflowers.

Penguins are those cute birds you've seen in nature documentaries or even in cartoons, strutting around Antarctica in their black-and-white plumage, like the emperor penguins we just heard. But now scientists have announced the discovery of ancient penguin fossils in Peru that remind us that we still have a lot more to learn about these popular birds. Veronique LaCapra reports.

LaCAPRA: Most people think of penguins as being adapted to the cold of Antarctica. But in 2005, paleontologists found the fossils of two new species — near the equator, in Peru. Julia Clarke, assistant professor at North Carolina State University, recalls being amazed by the discovery of these long-extinct species.

CLARKE: "When I heard about the new finds I rushed to get a team together and to go down there and work with my Peruvian colleagues on the new remains. The new fossils are from 42 and 36 million year old deposits, and it was completely surprising to find penguins during this time period, in equatorial regions."

LaCAPRA: Penguins evolved in places like Antarctica and New Zealand, and — until this recent discovery — scientists thought that they moved closer to the equator only about four to ten million years ago. But these two species reached present-day Peru more than 30 million years earlier.

And Clarke says one of them, Icadyptes salasi, was a giant:

CLARKE: "Icadyptes salasi would have stood around 5 [just over one and a half meters] tall and in fact the bones of these fossils are so well preserved that when the team saw this skull, the first skull of a giant penguin, we were, we were just taken aback. The overall skull is over a foot [30 centimeters] long, and the beak itself is extremely narrow and elongate that's very striking, and strikingly different than what we see, in any living penguin.

LaCAPRA: In fact, the giant penguin, and the other new species, Perudyptes devriesi are only distantly related to the penguins that exist today.

According to Clarke, these prehistoric penguins are among the oldest that anyone has ever found in South America. And they lived at a time when the earth was actually much warmer than it is now.

CLARKE: "The earth was a very different place. These penguins are really in the waning days of what we call the "greenhouse earth" of the Paleogene period. So we have all of this diversity within penguins that's actually during a time that the earth was lacking in polar ice caps.

LaCAPRA: So if these ancient penguins thrived under much warmer conditions, does that mean that today's penguins will easily survive global warming? Not so, Clarke warns.

CLARKE: "I feel very strongly that just because early parts of the penguin family tree did extremely well during these warm periods in earth's history, our new results can't be taken to say that any current global climate change would not negatively impact living penguins, because in fact there's a lot of evidence to suggest that living penguins may be cold-adapted, unlike most of the penguins that preceded them on earth."

LaCAPRA: Clarke also stresses that the climate is now changing much more quickly, than anything prehistoric penguins would have had experienced.

Her findings are published in this month's issue of the Proceedings of the National Academy of Sciences. I'm Veronique LaCapra.

Native Americans have lived in a place called Taos Pueblo, in what is now the American Southwest, for a thousand years. During all that time, radon, an invisible, naturally occurring and radioactive gas has been seeping up through the ground and into the traditional earthen adobe structures where people live and work. Radon exposure has been linked to lung cancer, but it wasn't a big problem there until a few years ago. As Eric Mack reports, officials at the Taos Pueblo Indian Reservation are trying to learn more about the mystery and to do something about it.

MACK: Taos Pueblo elder Lillian Romero is the director of the senior center here. She says one of the hot topics of conversation among the elders lately has been the sudden rise in cases of cancer on the reservation.

ROMERO: "They were talking about why we were having so much cancer, but since I didn't know anything about it, I thought I'd give Evelyn a call to see what she can do and then she did come over and she talked to us."

MACK: Evelyn Martinez is with the tribe's environmental department. She's spent most of her life here, but only learned about radon a few years ago. Since then, she's become convinced that the gas is playing a role in the increase in cancer.

MARTINEZ: "You know, there have been some deaths in our community as a result of lung cancer, and some of these people didn't smoke, so you have to scratch your head and wonder, 'well, it must be something like radon.'"

MACK: Scientists have documented that living with high levels of radon significantly increases the risk of lung cancer. It's the second leading cause of the disease in the United States, after smoking, according to the American Cancer Society. But why is it only affecting the reservation now? To begin her investigation, Martinez turned to the state's tumor registry, which has been tracking cancer cases in New Mexico for over 30 years.

Statistics there seem to confirm an unexplained and sudden jump in lung cancer. The numbers also caught the attention of Charles Wiggins, who runs the tumor registry:

WIGGINS: "It could be that we're just seeing the expansion of modern culture into these communities, but this is very interesting. I think even though it's a small number of cases, there's been other communities where we got insight just look at a handful of cases, so that never deters me wanting to look at something like that even though it's a small number of cases."

MACK: Elder Crisita Archuleta grew up on the reservation in the old pueblo village. A few years ago, Archuleta lost her husband to cancer.

ARCHULETA: "We never heard of cancer when we lived in the village where all the houses are made out of adobe."

MACK: And leaving those drafty, clay brick houses could be part of the explanation for why lung cancer has only recently become a problem.

When electricity became more accessible on the reservation in the 1970s, Archuleta and most other residents moved out of their ancient adobe village and into modern homes.

The new homes were built to be energy efficient and airtight.

According to Michael Taylor with the New Mexico Radon Control Bureau, that makes modern homes an ideal trap for radon.

TAYLOR: "They've got double-glazed windows, caulking, things to prevent and avoid drafts, but technology that's gone into the floors has been pretty primitive."

MACK: That means radon can seep in through floors, and when it does, it has nowhere to go. Its concentration in the indoor air can reach toxic levels.

MACK: Today, Evelyn Martinez is passing out radon test kits at the local school. No one knows for sure what's causing the lung cancer on the reservation, but she isn't taking any chances.

Martinez says she tested one home here that had radon levels three times higher than the government recommends. But costly venting systems to diminish the radon are out of reach for most people living on the reservation.

MARTINEZ: "A mitigation system can cost $1,800-2,000, people just don't have the means of the money to be able to pay for that. Right now all we can do is accumulate numbers and hopefully raise a flag here."

MACK: And that approach seems to be working. Taos Pueblo officials recently put a new ventilation system in the reservation youth center, and they are currently looking for more funding to tackle the problem in local homes. For Our World, I'm Eric Mack at Taos Pueblo, New Mexico.

MUSIC: "Our World" theme

That's our show for this week. We're always interested in your comments or your science questions. Email us at ourworld@voanews.com. Or use the postal address -

Our World
Voice of America
Washington, DC 20237 USA.

Rob Sivak edited the program. Eva Nenicka is the technical director. And this is Art Chimes, inviting you to join us online at voanews.com/ourworld or on your radio next Saturday and Sunday as we check out the latest in science and technology ... in Our World.

XS
SM
MD
LG