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National Geographic Magazine

National Geographic Magazine May 2013

The latest news in science, exploration, and culture will open your eyes to the world’s many wonders. Get a National Geographic digital magazine subscription today and experience the same high-quality articles and breathtaking photography contained in the print edit.

국가:
United States
언어:
English
출판사:
National Geographic Society
빈도:
Monthly
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1
food and water

There is a stream on my property in Rappahannock county, Virginia, that meanders through fields in its own sweet time, in its own sweet way. It’s a thread of water, narrow enough for me to leap over, modest in the grand scheme of nature, but I take my responsibility as its caretaker seriously. I keep wandering livestock out of the stream. I know their nutrient-rich manure turns water eutrophic, the scientific term for water overloaded with nutrients. I don’t mow grass along the edges but keep it long, as a buffer to absorb any fertilizer runoff from the fields, which could ultimately end up in the chesapeake bay and affect its fisheries. I try to be a good steward. the stream may be mine, but the water belongs to everybody. In…

4
restless genes

I beg to differ on the reasons for human migration to all corners of the world during the last 200,000 years. The last few hundred years of exploration represent less than one percent of human history and took place when humans had already occupied almost all the land on the globe. I believe that the migration of the human species in the other 198,000 years was the result of climate changes, a need for better foraging, and developed ways of living. Restlessness, curiosity, or a nomadic lifestyle did not play a role. STAFFAN PERSSON Madison, Alabama “Why We Explore” is why I’m a member. You bring us from our living rooms into the cold, hot, remote, high, low, barren, overrun, infested, and otherwise amazing places of our world. CHIP UNDERHILL Merrimack, New Hampshire The term “modern…

2
the payout

EXPERTISE Human migration archaeologist LOCATION Oman My team members are from across the world— Ukraine, Germany, Italy, the U.S.—but often we don’t have anyone from the Arabian Peninsula, where we dig for evidence of ancient humans. So during our first year in the field, before I’d learned Arabic and there was Google Earth to help, I took on a local Bedouin guide. When I asked his fee, he responded, “We are brothers. It is my joy to take you around these places.” With a field budget of about $12,000 that had to cover equipment, car rental, and fuel, plus food and housing for eight men, I was more than happy to believe him. Three days later, when it came time to part ways, he asked how much I was planning to pay him. I had…

1
your shot

This page features two photographs: one chosen by our editors and one chosen by our readers via online voting. For more information, go to ngm.com/yourshot. EDITORS’ CHOICE Eva Kraaijenbrink Leusden, Netherlands At an animal show near Barneveld, Netherlands, this Angora rabbit was being inspected for the quality of its fur, which is often used to make luxury sweaters and scarves. “It was lying so still, it looked almost dead,” Kraaijenbrink says. She zoomed in to see if it was still breathing. It was. READERS’ CHOICE Sylwia Domaradzka London, England On a tour of central Poland’s countryside last fall, Domaradzka saw many small battles between white-tailed eagles. These two birds in particular wanted to sit in the same spot. “There was an awful lot of fighting and bickering among them,” she says.…

1
prehistoric inferno

Despite their dominance at the top of the food chain, dinosaurs had it rough. New research suggests that before an asteroid likely ended their lives, dinosaurs in genera like Parksosaurus (above) and Psittacosaurus and their brethren roamed a fiery planet. Charcoal remnants from the Cretaceous period around 80 million years ago reveal that the atmosphere was loaded with oxygen—around 25 percent, compared with 21 percent today. That helped propel widespread wildfires triggered by lightning strikes, allowing even moist trees and shrubs to burn. Then, with sparse vegetation, major floods could have drowned entire regions. Paleobotanist Sarah Brown suspects that the fires were “a regular part of the dinosaurs’ lifestyle,” forcing mass migrations. Not to mention the stress of looking for unburned food. —Daniel Stone…

1
ring mastered

of Eindhoven is using circular reasoning. An elevated 360-degree bike circuit is the Netherland city’s answer to traffic congestion. Pedaling is not just a pastime in the region: About one-quarter of all transportation is by bicycle. Since bikes can’t go as fast as cars, they can precipitate jams, especially along the A2, the Netherlands’ most traveled north-south speedway. Open since last June, the bridge gives the local population of about a quarter million the option to ride above the gas-fueled fray. The bridge’s cable design with just one central support ensures that no sides are obstructed. “Users can connect in every direction,” says Adriaan Kok, one of the ring’s engineers. Though it seems to hover, the ring’s no pushover. Counterweights line the white inner ring to keep the structure stable, allowing…