Innholdsfortegnelse for JANUARY 2016 i National Geographic Magazine

Walk through the understory of a neotropical rain forest and you’ll see an unusual sight—brown or clear-winged butterflies gliding just above the forest floor, “like leaves floating on a stream,” says University of New Orleans entomologist Phil DeVries. They’re demonstrating something called the ground effect. It’s an aerodynamic phenomenon that occurs whenever wings are near a fixed surface, which increases lift and decreases drag. If you’ve been on a plane as it lands, you may have felt a brief floating sensation. That’s the ground effect. In a recently published study, DeVries and colleagues found that all but one species of Haeterini butterflies glide near the ground in this energy-efficient manner. Their evolutionary secret: forewings longer than those of their relatives, which favor flapping flight. Butterfly Forewing Shape…

When you head out to the desert, David Strayer is the kind of man you want behind the wheel. He never texts or talks on the phone while driving. He doesn’t even approve of eating in the car. A cognitive psychologist at the University of Utah who specializes in attention, Strayer knows our brains are prone to mistakes, especially when we’re multitasking and dodging distractions. Among other things, his research has shown that using a cell phone impairs most drivers as much as drinking alcohol does. Strayer is in a unique position to understand what modern life does to us. An avid backpacker, he thinks he knows the antidote: Nature. EXPLORER The Channel series explores the “Call of the Wild” on January 10. On the third day of a camping…

Sometimes you just want to spend a few hours washing your truck. It’s a beautiful day, all of northern Thailand vibrant in the spring sun, so you drive your new Isuzu into the stream that runs through your village, Tung Nha Noi. Cows and people walk by as you stand in the water, a 21-year-old guy with a hot ride, sponging it so clean that the vehicle gleams like hope in the sun. Not so long ago the chances that someone like Piyawot Anurakbranpot—“Chin” to his friends—would have a fancy truck at such a young age would have been close to zero. People in remote villages like Tung Nha Noi didn’t have the money. But recently families like Chin’s have become much more prosperous. The reason is visible in the…

Marine biologist David Gruber specializes in finding life-forms that biofluoresce— creatures whose uniquely structured skin absorbs undersea deep-blue light and reemits it as neon green, red, or orange. Gruber, whose work is supported by the National Geographic Society, has found biofluorescence in jellyfish, corals, a sea turtle, and more than 200 fish and shark species. Now the diver-scientist is expanding his research beyond how these fish look to explore how they see. Gruber had a Cornell University eye specialist examine a “brilliantly fluorescent” swell shark (above). Humans’ eyes see a broad spectrum of colors. This shark “sees only in the blue-green range,” Gruber says, but in that range it sees acutely. Armed with an underwater camera that mimics the shark’s vision, he hopes to learn how biofluorescence helps the shark…

The higher temperatures and more extreme weather that come with climate change likely will have wide-ranging and mostly negative consequences for human health. They threaten air and water quality along with our ability to produce food, and they’re sure to promote the spread of diseases like dengue fever. Governments, especially in developing countries with weak health care infrastructure, need to prepare for this volatility, says Raman Velayudhan of the World Health Organization. But that takes resources many don’t have. THE POTENTIAL DAMAGE 250,000 NUMBER OF ADDITIONAL DEATHS CAUSED BY CLIMATE CHANGE IN 2030 DIRECT HEALTH SERVICE COSTS PER YEAR BY 2030* $2-4 billion * Doesn’t include costs due to agricultural, water, and sanitation changes VECTOR-BORNE DISEASES Many illnesses caused by pathogens and parasites are transmitted by bloodsucking insects. Their ranges…

At sunset the wildebeest seems doomed: Sick or injured, it’s wandering miles from its herd on the Serengeti Plain of Tanzania. By sunrise the loner is dead, draped in a roiling scrum of vultures, 40 or so birds searching for a way to invade its earthly remains. Some of the scavengers wait patiently, with a Nixonian hunch, eyes on their prize. But most are engaged in gladiatorial battle. Talons straining, they rear and rake, joust and feint. One pounces atop another, then bronco rides its bucking and rearing victim. The crowd parts and surges in a black-and-brown wave of undulating necks, stabbing beaks, and thrashing wings. From overhead, a constant stream of new diners swoops in, heads low, bouncing and tumbling in their haste to join the mob. Why the…

In the lush jungles of northeastern India, hard against the Bangladesh border, is a tiny village with an unconventional social order. Mawlynnong is where about 500 members of the indigenous Khasi tribe still follow ancient matrilineal traditions. Where succession, money, property, and power pass from mother to daughter. Where girls—literally—rule their roosts. Karolin Klüppel wanted to see this inverted world for herself. So for nine months spanning two years, the Berlin-based photographer lived with different Khasi families in the “unbelievably clean, calm, and peaceful” village. What she found was a culture in which youngest daughters (called khadduh) inherit wealth and property, husbands move into their wives’ homes, and children take their mother’s surname. Girls go to school in the village until they’re teens, though some move to the state capital…

A hundred years ago in the early months of 1916, America stood possessed of a magnificent, visionary, slightly confused and inchoate idea: national parks. These would be parks for the American citizenry, not pleasure grounds or private hunting reserves for nawabs and kings; parks to be shared, even, with visitors from around the world. At that point 14 national parks already existed in the United States, the oldest being Yellowstone, which had been set aside by federal law, back in 1872, as the first national park anywhere in the world. The other U.S. parks, representing a diverse sample of majestic landscapes, all west of the Mississippi, included Yosemite in California (originally a state park, nationalized in 1890), Wind Cave in South Dakota (1903), Glacier in Montana (1910), and Rocky Mountain…

The sea ice that blankets the Arctic Ocean isn’t the unbroken white mantle depicted in maps. It’s a jigsaw puzzle of restless floes that are constantly colliding, deforming, and fracturing from the force of wind and ocean currents. Last February I stood shivering on the deck of the Lance, an old Norwegian research vessel, as it picked a path through a labyrinth of navigable fractures. A barren white plain of ice and snow extended to the horizon in every direction. The ship’s steel hull shuddered and screeched as it plowed through floating chunks of jagged ice. The Lance was seeking a solid patch of ice to attach to—the last one had shattered—so that it could resume its erratic drift across the frozen sea, charting the fate of Arctic sea ice…

National Parks After 55 years of travel across the country and around the world, last year I finally made it to one of America’s iconic places—Yellowstone, the first national park and the ideal of what protected lands should be for sheer grandeur, conservation, and outreach. Why did I wait so long? The inscription on the Roosevelt Arch, at Yellowstone’s north entrance, is a quote from the act that created the park in 1872: “For the Benefit and Enjoyment of the People.” Those words ring true today. Joining a half dozen National Geographic photographers assigned to shoot the Greater Yellowstone ecosystem from the Grand Tetons in Wyoming to its northern border in Montana, my husband and I canoed tranquil rivers searching for otters. We hiked a landscape alive with burbling pools…