Innholdsfortegnelse for Jun-15 i National Geographic Magazine

The sunscreen you put on your skin doesn’t stay there. Up to 6,600 tons of sunscreen wash into coastal waters each year. That’s bad news for swimmers, who end up unprotected from the sun—and also for fish, according to a report from the Spanish Research Council. When nanoparticles from one of sunscreen’s main ingredients, titanium dioxide, mix with water and sun, the result is hydrogen peroxide. It kills phytoplankton that nourish fish and, ultimately, the rest of the food chain. Researchers don’t encourage people to wear less sunscreen. The solution is for producers to create eco-friendly substitutes, says marine ecologist Cinzia Corinaldesi. For more than a decade, sunscreen makers have been on the hunt for a new chemical formula that hardly leaves a trace.…

Coral reefs are among the world’s most at-risk ecosystems, and among the biggest threats to them is climate change. Rising water temperatures contribute to coral bleaching and die-offs, and acidification makes it hard for coral polyps to build the skeletons that form the reef. “Climate change can distress even the best managed and most remote reefs,” says Mark Eakin of the National Oceanic and Atmospheric Administration. Local activities—coastal development, overfishing, pollution—can also hurt corals. But good management can make reefs more resilient, allowing them to bounce back if conditions improve.…

At first glance, a 120-million-year-old fossil from north eastern China appears to be a nest of babies with an older companion, perhaps a sibling babysitter. “I see that as easily as everyone else,” says paleontologist Brandon Hedrick, who studied the unusual group recently. Farmers had excavated the fossil, which is almost three feet across, but they didn’t get surrounding features, such as the edge of a nest, that would help explain what the dinosaurs were doing. The more Hedrick dug into the details, the less this looked like a bunch of nest mates. He offers two other possibilities. The dinosaurs may have been hiding in a burrow that collapsed and crushed them. Their species—named Psittacosaurus, or “parrot lizard,” for their large beaks—perhaps lived in large herds. “They were extremely successful,”…

Marijuana’s advocates believe the long-maligned plant can enhance life—and help deliver people from sickness and pain. A Seattle cannabis worker cradles the resin-dusted bud of a strain called Blueberry Cheesecake. There’s nothing new about cannabis, of course. It’s been around humankind pretty much forever. In Siberia charred seeds have been found inside burial mounds dating back to 3000 B.C. The Chinese were using cannabis as a medicine thousands of years ago. Marijuana is deeply American too—as American as George Washington, who grew hemp at Mount Vernon. For most of the country’s history, cannabis was legal, commonly found in tinctures and extracts. Then came Reefer Madness. Marijuana, the Assassin of Youth. The Killer Weed. The Gateway Drug. For nearly 70 years the plant went into hiding, and medical research largely stopped.…

Unika Vajracharya could be standing on the brink of divinity, about to become one of Nepal’s most celebrated figures. She is six years old, at present a simple schoolgirl. Despite her shyness, her eyes sparkle with curiosity. She isn’t used to receiving strangers. A smile dimples her cheeks when I ask her what she’ll do if, later today, she’s chosen to be a kumari, or living goddess, a role that will bring people to their knees before her. “I’ll keep quiet,” she says. “I won’t be allowed to go to school. I’ll study at home and receive worship every day.” Unika is a Nepali from the Newar ethnic group. She lives in Patan, officially known as Lalitpur, a city of 230,000 people of mainly Buddhist influence in the fertile Kathmandu…

PROOF A PHOTOGRAPHER’S JOURNAL proof.nationalgeographic.com The eye is an organ of extreme perfection. I have a strong interest in evolution, and eyes have developed stunning adaptations over time. This may fly is a male with what are called turban eyes—greatly enlarged eyes at the top of the head in the shape of a turban. The male uses his eyes to scout for the silhouette of a female in the dim light of dusk. He doesn’t even have a working mouth. If you live for only one day, as adult males usually do, you don’t need to eat. But you do need tremendous eyes to find a female before you die. I am a cancer researcher, but I also work as a science photographer under the name “Micronaut.” The “micro” is…

nationalgeographic.com/3Q Persis Drell put her mind to math in seventh grade and found she loved it. In college she had a great female physics professor, and physics became “a passion.” Now dean of the School of Engineering at Stanford University, Drell, 59, previously headed the National Accelerator Laboratory there and oversaw cutting-edge research with the world’s most powerful x-ray free-electron laser. Talk about going into science when few women did. After four years at an all-women’s college, the first year I went to Berkeley for physics grad school, I was the only woman in my class. What I remember most vividly was being in classrooms with 45 to 50 others and being the only woman. I didn’t raise my hand to ask questions, because if one of the guys asked…

When things heat up down under, koalas know how to keep their cool. Now, thanks to infrared photography, humans can see how they do it. A 2014 study led by University of Melbourne ecologists showed that when summer temperatures climb up—often above 104°F—koalas climb down, pressing their bodies close to the trunks of trees. Each tree has its own microclimate, says researcher Natalie Briscoe, and can be more than 12°F cooler than the air. So for a koala, whose belly fur is relatively thin, tree hugging is like standing in front of an open fridge. As a way to regulate body temperature, it’s more efficient than panting or fur licking—koala-cooling methods that use twice as much water. In a separate study, University of Sydney biologist Mathew Crowther found that koalas…

Stretching more than 1,400 miles, this reef system—the world’s largest—is under pressure from climate change. Sea-temperature rise, acidification, and more intense weather events such as cyclones are putting the reef’s more than 400 corals and 1,500 fish species at risk. A study led by the Australian Institute of Marine Science found that between 1985 and 2012 the reef lost half its coral cover, or living polyps. CORAL BLEACHING Bleaching is a top cause of coral death. In 1998 rising water temperatures killed 16 percent of the world’s coral reefs. Warming water triggered widespread bleaching in 2014, but scientists are still calculating the damage. HEALTHY CORAL Most polyps have a symbiotic relationship with the algae that live in them and provide up to 90 percent of their food. Algae also give…

Lemurs come from one of the oldest branches of the primate family tree: Their ancestors date from the Eocene, as long as 55 million years ago. Intelligent creatures, they’ve had epochs to evolve, adopt beneficial behaviors, and refine social systems. Where have they wound up? With the females in charge. Though matriarchy is rare in primates, female dominance is the norm for most lemur species, including the Coquerel’s sifaka, seen here. Even the youngest females can pull rank on any male, and females get first choice of foods and resting sites, says Chris Smith of the Duke Lemur Center. “We’ve seen females take food out of males’ mouths. And if he’s in a sunny spot she wants, she can just move toward him, and he’ll make a submissive cackle and…

More than 20 million Americans used marijuana in 2013. Possession and sale are illegal under federal law, but medical use is legal in 23 states and the District of Columbia. Many states also have reduced or eliminated penalties for recreational use, resulting in a patchwork of restrictions and availability for those seeking medical help or just a casual high. Marijuana is rising in popularity… Recreational users outnumber medical users. Despite the risk to their developing brains, a third of teens say they’ve used marijuana in the past month. and increasingly available in U.S. states… As states loosen restrictions, one politically appealing option is cannabidiol (CBD) oil, which has some of marijuana’s health effects without the high.…

A century ago on the flanks of Mount Field in Canada’s Yoho National Park, Charles Doolittle Walcott, then secretary of the Smithsonian and one of the most famous paleontologists of his day, found two life-changing things. The first discovery was what is arguably the world’s premier fossil bed, a quarry that now bears his name. The second discovery was his third wife, Mary Vaux, after whose family he would soon name a genus of fossilized sponges, Vauxia. It is natural that modern visitors to this most sublime and overlooked of the Canadian Rockies parks would focus on the first of these discoveries. The Burgess Shale formation that encompasses the Walcott Quarry was named a UNESCO World Heritage site in 1980. A few years later, in the best-selling book Wonderful Life,…

A treetop platform provides a sweeping view for a flag-bearing fire lookout in California’s Mount Shasta National Forest in 1924. How did he climb so high? “The earliest towers were constructed with the materials readily at hand—primarily wood,” notes Cheryl Oakes of the Forest History Society. “But this one was near a tree nursery and may have had metal available for a ladder.” Early detection—fire finding over firefighting— became a priority for the U.S. Forest Service after flames swept through some three million acres in Idaho, Montana, and Washington in August 1910. The two day blaze known as the Big Blow up is still considered the largest fire in U.S. history.…

The intercontinental superhighway has come a long way since the first copper telegraph line was strung across the Atlantic seabed in 1858, transmitting a few words a minute. Soon the Hibernia Express, the first new transatlantic fiber-optic cable in ten years, will be able to flash the equivalent of 125 years of National Geographic magazine in 30 milliseconds. Some 580,000 miles of cables cross the ocean floors, a vast system of fast lines carrying almost all the world’s digital traffic. The latest lines link fast developing lands, avoid congestion, and shave milliseconds from connection times.…

As technology gives dodos a closer look, their image may get a second chance. College of the Holy Cross paleontologist Leon Claessens and a team of researchers recently used a 3-D laser scanner on the world’s only complete dodo skeleton. The result—the first digitized dodo—may answer age-old questions about how the three-foot-tall, flightless birds looked, walked, and behaved. The dodo’s rep as an evolutionary failure is “entirely undeserved,” Claessens says. Dodos thrived on Mauritius for thousands of years before the Dutch came in 1598. By 1693 dodos were extinct, “a case study of human disruption.”…

For something that covers most of the planet, the ocean is a pretty murky frontier. Scientists say technically there’s just one connected global ocean, but people far more commonly refer to several, as in the Atlantic, the Pacific, the Indian. More confusing is why the lines separating these basins— divisions first formally recognized in 1928—have remained largely unchanged. “The boundaries reflect geopolitics” rather than the way the water actually circulates, says mathematician Gary Froyland of Australia’s University of New South Wales. He and Imperial College oceanographer Erik van Sebille proposed a new map, redrawing borders based on modern knowledge of currents and the natural basins they form, as well as the currents’ relationship to a pressing environmental problem: trash. Plastics and other debris have been drifting for decades in the…

Daily Dozen Editors pick 12 photos from those submitted online each day. Here are our favorites this month. John Trent Dorchester, England  Trent saw a flamingo while visiting a Florida amusement park. He approached it late in the day after the crowd had thinned. “Photographing the whole bird was never my intention,” he says. “All the expression was in the head and wings.” Jismon P. Thiruvananthapuram, India In a zoo in his hometown, the photographer saw a large herd of deer assemble for a mid afternoon feeding. He shot the photo in color, then converted it to black and white to highlight the animals’ spotted coats.…

UNDERSTANDING DOLPHINS INTELLIGENCE CAPTIVITY CULTURE a three-part series In early January 2011 Jeff Foster, a 55-year-old marine mammal expert from Seattle, arrived on the stony shore of a pristine bay near the small village of Karaca, situated in a corner of the Gulf of Gokova on Turkey’s southwest coast. Just offshore was a collection of floating pens used to farm fish. In one of them, which had been modified and measured about a hundred feet across and 50 feet deep, two male bottlenose dolphins swam in slow circles. Tom and Misha, as they were called, were in lamentable condition. As far as anyone could tell, they’d been captured in the Aegean sometime in 2006, and almost nothing was known about their lives in the wild. After starting their captive lives…

“This is what the end of the world looks like,” says Yusup Kamalov, sweeping his hand toward the scrub-covered desert stretching before us. “If we ever have Armageddon, the people of Karakalpakstan are the only ones who will survive, because we are already living it.” From our perch atop this sandy bluff in northern Uzbekistan, the view could be of just about any desert—that is, if it weren’t for the mounds of seashells and the half dozen marooned fishing boats rusting into the sand. This spot was once the tip of a peninsula jutting into the Aral Sea, which up until the 1960s was the world’s fourth largest inland body of water, covering some 26,000 square miles—an area larger than the state of West Virginia. Behind us lies the town…

You might remember this TV antidrug ad. “This is your brain,” says a grim-faced guy. He holds up an egg. “This is drugs,” he says, gesturing to a skillet on the stove and then cracking the egg into the hot pan. “This is your brain on drugs.” The egg sizzles and congeals. “Any questions?” Well, yes—lots of them. And decades after this crusade aired, relatively few have been answered, especially about marijuana. Now that nearly half the states in this country allow medical marijuana, voters in four states have legalized pot for recreation, and a majority of Americans favor legalization, research about how marijuana affects our brains and bodies is an urgent issue. There is less hard science about marijuana than you might think. “For nearly 70 years the plant…