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MUSIC: Our World theme

Straight ahead on this special edition of "Our World," we revisit some of our favorite stories of the past year ... mountain-top astronomy in Hawaii ... a backpack that generates electricity ... and studying deep-sea corals. Those stories, DNA genealogy, and more.

Maybe you studied geography in school, looking at maps and learning about your country's natural features. An emerging specialty in the field is "medical geography," combining traditional tools of map-making with medical data to provide important insight into the spread of disease. VOA's Keming Kuo wrote our report, which is read in the studio by Faith Lapidus.

LAPIDUS: Mention the profession "geographer" and most people think of the traditional roles of mapmakers, or explorers studying exotic cultures. But the scope of geography has expanded forming hybrids with some very different fields.

When Lee De Cola teaches a class, he often brings a projector filled with the images of dozens of colorful maps, showing how Lyme Disease, West Nile Virus or some other malady has spread across the United States. Mr. De Cola is one of just a few hundred medical geographers in America, so it's not surprising that he draws puzzled looks from those asking about his work:

De COLA: "When I meet people on an airplane, they say, 'Medical geography, that sounds interesting. What's that all about?' All I have to do is tell them, 'Have you seen a map about AIDS recently?' They say, 'Sure.' That's medical geography: 'the Why of Where.' Everything happens somewhere. So when we map it, it becomes much more illuminating to see a map of something, instead of talking about it in the abstract."

LAPIDUS: Although medical geography became an official specialty area a few decades ago, its roots may actually be traced to ancient times. Mr. De Cola, a research scientist at the U.S. Geological Survey, says it all started with the Greek doctor Hippocrates, known for his Hippocratic Oath, which emphasizes: "Above all, do no harm."

De COLA: "Many of the phenomena we now call geography influenced people's health. The quality of the water, the atmosphere, what lifestyles people had, what they ate? What health they had was determined by geographic phenomena. Here was a scholar writing 2,000 years ago about the very same issues we're talking about today."

LAPIDUS: In the mid-19th century, British doctor John Snow used medical geography principles to locate the source of a cholera epidemic in London, as Mr. De Cola explains.

De COLA: "He showed a map of cases of cholera clustered around a pump that led him to suspect that it was the pump itself that was the source of polluted water that was giving people cases of cholera. That was medical geography.

LAPIDUS: Mr. De Cola says the crossover has spurred more cooperation between geographers and such health organizations as the Centers for Disease Control [CDC]:

De COLA: "The collaboration is really growing and it's in its very early stages. I was down at CDC last year and realized that not only could we take information about diseases and make maps of it, but we can turn that process around -- and start asking spatial questions and use spatial information to help organize the information itself."

LAPIDUS: Thus, Lee De Cola and other medical geographers are combining a variety of social, economic and environmental data with the source and spread of disease:

De COLA: "Putting all these things together, we [ask], 'Is there something unusual going on here? Is it an outbreak of a mosquito-borne disease? A bio-terrorism event? An oil spill here?' Something like that."

LAPIDUS: In the future, Mr. De Cola says medical geography will continue as an important part of medical research which, itself, will experience fast growth.

De COLA: "Bio-medicine is an exploding field. The American economy devoted over a trillion dollars to personal and public health expenditures. That number is increasing much more rapidly than the economy as a whole."

LAPIDUS: Lee De Cola is one of the small-but-growing number of medical geographers who are using the analytical and mapping science of geography and applying it to medical research.

Back in April, the National Geographic Society announced an ambitious program to trace the history of human migration through the analysis of DNA of indigenous peoples. The five-year Genographic project, as it's called, aims to collect blood samples from 100,000 people around the world, then apply sophisticated technologies to identify certain segments of DNA that can be associated with migrations of populations at some point in history. For example, project director Spencer Wells explained to Mongolian-born Battur Tumur what his DNA revealed.

WELLS: "This traces its origin, of course, back to Africa, and it delineates an expansion out of Africa roughly 50,000 years ago that followed a coastal route along the south coast of Asia. It reached Australia by around 45- to 50,000 years ago, and some of these individuals would have turned northward in East Asia, ultimately migrating back into Mongolia, which is where your ancestors come from. So it's a very typical Mongolian lineage."

Also typical, perhaps, in that his DNA indicates Mr. Tumur is a direct descendant of Ghengis Khan, the 12th century warrior, a hero to Mongolians and a prolific man who is said to have fathered thousands of children. Using DNA to track migrations over not just years but millennia could provide a powerful new tool to scientists. National Geographic president John Fahey says that, until now, the best evidence came from the study of bones and rocks.

FAHEY: "But now we have new technologies and new sciences that can help us as well in terms of really understanding the migration and origins of man. And I think it's a perfect companion to the fine work that we've been doing with paleoanthropology for years."

Scientists involved in the Genographic project hope to learn more about how humans spread out from origins in East Africa to become the diverse species we are today. Ted Waitt, whose family foundation is helping fund the project, stressed the urgency of the effort as traditional ways of life disappear.

WAITT: "The ethnic populations this amazing team are going to study are indeed reflections of humanity in all its uniqueness and splendor. Exploding urban populations and homogenizing effect of globalization endangers many of these cultures. And while genetic clues are still present and likely most pure in their DNA, the snapshot this research is attempting to take will not be present forever."

American Indians are among the indigenous people who will participate in the project. Phil Bluehouse of the Navaho Nation in Arizona choked up after hearing of his ancestral journey out of Africa, as told by his DNA.

BLUEHOUSE: "It's always been a dream. It's always been something that was in me, that finally I was able to say, yeah - it's been confirmed. It's been there genetically, and that's what the genetics was trying to tell me, that you did come from somewhere. And I think that I did shed tears, and it was tears of joy because I think it's very important."

Members of the public can have their own DNA analyzed for about $100. Part of that money will help fund the collection of DNA from the indigenous peoples, and for cultural preservation. Project leaders say one of its key goals is to raise awareness of the pressures facing indigenous groups. One of its challenges will most certainly be convincing the indigenous groups they approach of their good intentions.

Project director Spencer Wells says he'll look for the answer in the genetic family tree we all carry.

WELLS: "Now, where DNA actually carries this story -- written in its code of bases A, C, G and T -- it shows us the connections between people all over the world, serving as a kind of genetic thread, connecting people who didn't realize, perhaps, that they were related."

In August, we took a radio journey to one of the most scientifically productive places on earth -- a dormant volcano that houses a cluster of state-of-the-art telescopes where astronomers are trying to unravel the secrets of the universe.

With clear, dry and pollution-free air, the world's highest island mountain, Mauna Kea, Hawaii, is the perfect place to get up-close and personal with the cosmos.

VOA's Rosanne Skirble is our guide.

SKIRBLE: Astronomers must compete for observation time on Mauna Kea. Tourists are welcome anytime to hike up the 4,205-meter summit or to join a guided caravan tour that departs from the Mauna Kea Visitors Center. This is where guide Erik West hands out some basic advise:

WEST: "You do need a 4-wheel drive vehicle and there are some health and safety issues. You cannot have any heart or respiratory problems, be under 16 years of age or have scuba dived in the last 24 hours."

SKIRBLE: Erik West readies drivers for the trek up.

WEST: "Alright, do you have your vehicle (gear) already in 4-wheel drive low? All set to go and you played with your gas tank and have that set (too)?"

SKIRBLE: One behind the other, the cars follow a steep gravel road that switches back and forth for during the 45-minute drive. The sedges gradually give way to a barren moonscape of lava rock and cinder cones.

As we reach the summit and park our vehicles, the complex of domed observatories suddenly loom like a garden of giant mushrooms.

The first large telescope was built on Mauna Kea in 1970. Since then, others followed.

WEST: "There is a total of 13 groups of observatories. One of them SMA (Submillimeter Array) - is actually (comprised of) eight different telescopes. There are 11 different countries that are involved. And over here we have the biggest telescopes ? the 10-meter Keck telescopes. And, the reason that they keep getting bigger and bigger as technology allows is that we want to be able to collect as much light as possible up here. So, the bigger you are, the more light you can see."

SKIRBLE: The twin Keck One and Keck Two are the worlds largest optical and infrared telescopes. Their mirrors are divided into 36 hexagonal segments, which work together as a single piece of reflective glass. During the day Keck One is a sleeping giant of steel beams and silent gears closed inside a protective shell. Erik West says the real action begins at sundown:

WEST: "The dome weighs about 700 tons protecting this thing. Its goes up ?about 10 stories to the top of the dome and the whole mirror structure is about 8 stories (tall)., and the dome will open up and start rotating to where they need it and the mirror rotating to where they are going to be observing. And, throughout the night, if it is following an object, it will be moving very slightly to follow it as it moves across the sky. But there won't be anyone in here generally. They will be in the control rooms staying warm."

SKIRBLE: Over the years, astronomers have discovered new moons around Jupiter, taken pictures that help measure the expansion of the universe and have observed hundreds of small objects orbiting the Sun past the orbit of the planet Neptune.

Each movement, each gear, each wheel guiding these massive telescopes is remotely controlled. Astronomers review the data, not from an eyepiece, but from a desktop computer.

This is where Rolf Kudritzki likes works. He is the director of the Institute for Astronomy, which manages Mauna Kea.

Rolf Kudritzki says that despite such sophisticated equipment projects often failnot every astronomer at Mauna Kea finds what they are looking for.

KUDRITZKI: "Because in modern astronomy we look at things which are barely detectable, faint at the margin of feasibility all the time because we are just pushing the frontier of our detections farther and farther away. So it is not always clear that such an observation really will be successful."

SKIRBLE: Rolf Kudritzki says that compared to space telescopes, land-based observatories like those atop Hawaii's Mauna Kea mountain provide astronomers with less expensive observing time and a more diverse array of tools for observing the heavens. Mr. Kudritzki predicts confidently that the Mauna Kea observatories will continue to complement earth orbiting telescopes for many decades to come. I'm Rosanne Skirble

Rescue workers in remote areas need electric power. Sometimes they need a lot; other times they need just enough to charge batteries on a mobile phone or power a laptop computer. The same applies to military forces or scientists on an expedition. That usually means carrying a supply of batteries for a wide range of mobile devices.

Now, scientists at the University of Pennsylvania have developed a new way of generating electric power by harnessing the up-and-down motion of a backpack.

Lawrence Rome described his invention in September, in the journal "Science."

ROME: "I've developed a passive device called a suspended-load backpack, which allows the user to generate electricity when they're walking down the street, and this electricity is important for anybody working in a remote area, whether they're using cell phones, GPS or other communication or scientific devices."

The backpack has a rigid frame, and the load is attached to the frame with springs. The motion of the load is then transferred to a small generator using a rack-and-pinion arrangement like many cars use for steering. The system produces up to about seven watts of electricity in normal use -- enough to recharge small, battery powered devices commonly used in remote areas.

Professor Rome says the system works best with a full -- heavy -- backpack.

ROME: "Definitely the more mass, the more electricity because there's more mechanical work that's being done, because you're moving a larger weight the same vertical distance. And another thing is, the faster you walk, the more electricity [you produce] as well.

So if the backpack is now generating power, you would think the person carrying it would have to work harder. And that's true. There is no free lunch. But apparently there is a discount, since it seems to take less energy to carry the same weight in a spring-loaded backpack. Because of this greater efficiency, it may be easier to lug your stuff in a spring-loaded backpack even if you don't need to generate electricity.

ROME: "It's true, the metabolic rate goes up about three percent, but we were expecting it go up much larger [amount], and what that must mean is that the cost of just the walking part of it has actually had to go down."

Commenting on the new backback in a separate article in Science, mechanical engineering professor Arthur Kuo of the University of Michigan said he expects that, as impressive as the new backpack technology is, there is a lot of room for improvement.

KUO: "This was just a prototype, so I don't think they had the opportunity to really experiment with the device and try different combinations of masses and springs. My expectation would be that if you got a lot more power than what they got -- so they generated about 4 watts -- and I think that there's no reason why they shouldn't get a lot more than that. And then, it's even conceivable that the total cost of walking and powering the generator could be lower than the cost of wearing a conventional backpack."

The backpack developer, Lawrence Roth, told me he has formed a company to commercialize his invention. I suggested the name "Power Pack," but he said they're going with "Lightning Packs," which is even better.

For me personally, perhaps the most interesting story I covered this year was my visit to a research ship studying deep sea corals off the coast of the southeastern United States. Because of the untimely arrival of hurricane Wilma, the ship was docked safely at Charleston, South Carolina, not out at sea.

Standing in a low-ceilinged workroom aboard the ship, the Seward Johnson, surrounded by computers, video gear and nautical charts, chief scientist Steve Ross explained how the coral specimens they bring up from the bottom provide a window into the past. Coral growth can be seen in rings -- tiny versions of the growth rings of trees -- that serve as a library of information about ocean conditions in the distant past.

ROSS: "You know, you probably heard that you can count the age of a tree by its rings. But the width of the rings gives you information about its growing season. You can tell potentially whether it was a wet climate or a dry climate, hot or cold, good or bad for growth. This is a little bit different situation, but we've determined that a lot of these corals live to be quite old. Anywhere from a few hundred years old to almost 1,000 years old potentially."

Analyzing those growth rings for isotopes of chemical elements -- including carbon and nitrogen and oxygen -- opens a window on the ocean environment in centuries past.

ROSS: "So we can go back to, say, potentially the year 1700 and find out what the temperature of the ocean was, what the pollutant load was, and what the status of the productivity was. And we can do that every year up to the present."

One of the first questions asked by the visiting journalists was, have you discovered any new species? The short answer we got from the researchers is, maybe, but the final word will have to await further study of specimens in land-based labs, after this expedition ends.

The identification of new species isn't what it used to be.

For centuries, biologists compared characteristics of an plant or animal to other similar organisms, not only to determine whether they were looking at a new species, but also to see how species were related to each other. You don't have to be a scientist to realize that a tiger is pretty closely related to a lion, but only distantly related to an elephant.

Martha Nizinski is a zoologist with NOAA, the U.S. ocean research agency sponsoring this expedition. Her approach to taxonomy -- the classification of organisms -- is the traditional method.

NIZINSKI: "Well, when you're doing taxonomy and identification, you use a lot of the old literature. So some of these species may have been described in the early to late 1800s, early 1900s. So we have to look and see how it compares to those original descriptions."

Dr. Nizinski explains the unknown organism is studied with careful attention to a variety of physical attributes.

NIZINSKI: "We'll use a crustacean as an example. We take measurements of its carapace, which is its shell. We look at various combinations of spines, the shape of the shell, the shape of the organism, how it carries its abdomen, the type of legs it has -- so there's a whole variety of characters that we look at."

But many other taxonomists now use DNA to classify species. Another member of this expedition, Cheryl Morrison, uses genetic identification. She says it's particularly useful with coral, where the shape and structures can be greatly influenced by the environment in which it grows.

MORRISON: "You know, looking like a very long branching pattern in one area, and then a little glob of coral polyps all over the place in another area, but it's really the same species -- it could be, it might not be. And so the genetics helps us in those types of situations figure out if we're really looking at the same thing."

DNA taxonomy uses basically the same technology used in police investigations, except that instead of tying a suspect to the crime scene, it tracks genetic similarities between known species and an unknown specimen. Although she has embraced the new method, Dr. Morrison doesn't reject the older.

MORRISON: "I wouldn't say it's better. I would say that they should go side-by-side, hand in hand. There are times where things are very similar, that we couldn't tell apart by morphology, but sometimes DNA allows us to separate things that we wouldn't have been able to, based on morphology. But often -- and I think that this is when this is the strongest technique -- is when they agree."

Of course, sometimes they disagree. So if these scientists exploring the edge of the continental shelf in the Atlantic Ocean off the southeastern U.S. do identify a new species, so what? Chief scientist Steve Ross and the other scientists on board the ship may be focused on knowledge and discovery, but the taxpayers supporting this government-funded expedition might wonder, how am I going to benefit?

ROSS: "Usually that's the stumbling block question for most of us, and we say, gosh I'm not sure. But quite a lot of the time we're accumulating information such as, there are biomedical potentials. We're not doing biomedical work, but some of the organisms in the deep sea have biomedical potential. There are groups [of researchers] that are beginning to explore that. That has a worldwide impact. Cancer research chemicals, for instance, is one area where deep sea research has been important."

You can learn more about this and other ocean research missions on their website at oceanExplorer-dot-n-o-a-a-dot-gov, or get the link from our site,

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That's our show for this week. Thanks to Rosanne Skirble for sitting in last week. We're always delighted to hear from you. Ask us a science question, tell us what you like about the program, or what you don't like. Email us at Or use the postal address:

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Our show was edited by Rob Sivak. Eva Nenicka is our technical director. And this is Art Chimes, inviting you to join us online at or on your radio next Saturday and Sunday as we check out the latest in science and Our World.