DiscoverSeptember 2015的目錄

A simple stone could rock your world. When I was 12, I spent a hot summer day digging up a rock in my yard. It kept dinging my mower blade, and I was sick of it. But annoyance quickly turned to fascination as I realized that this rock was rectangular, with beveled edges. Its placement there at the edge of our old cobbled driveway was no accident of nature. It’s a gravestone, I thought. In fact, it was a carriage step, a remnant of the 19th-century house that once stood on our land. A simple thing, that stone, but it rocked my world, filling me with a sense of discovery so profound that even now my stomach gets fluttery when I think of it. It’s that same way Ufuk Kocabaş…

Your body responds to changes in what you eat — for better or worse — much faster than you might think. That’s what researchers discovered during a recent study on the link between diet and colon cancer risk. The project involved trading the typical diets of two groups: African-Americans, who are at high risk for colon cancer, and rural South Africans, who have a much lower risk for the disease. After two weeks of eating the high-fiber, low-fat and low-animal-protein South African diet, African-Americans in the study saw a significant decrease in inflammation and levels of several biomarkers considered predictive of colon cancer risk. At the same time, the South African participants’ level of risk increased. Shortly after the study was published in Nature Communications, lead investigator Stephen O’Keefe, a…

Just a few million kilometers away lurks a mysterious, and possibly deadly, asteroid called (29075) 1950 DA. Since the rock’s discovery 65 years ago, scientists have learned the roughly mile-long body actually consists of a loose collection of smaller rocks, which they presumed were held together by their own gravity. But in 2007, scientists discovered that 1950 DA also spins quickly, once every two hours — far too fast for gravity to hold it together. How could this pile of rubble not tear itself apart? In August, physicists at the University of Tennessee announced that the force that holds 1950 DA together is the same force that allows the fine hair on a gecko’s feet to stick to vertical surfaces: namely, weak electric attraction between individual molecules, called van der…

One of the first things Doug Heil noticed was the gibberish on the screen. It was March 2014, and Heil was at his computer, filling out work orders for the construction company he runs in the San Gabriel Valley of Southern California. All of a sudden, he could no longer string the letters together to form a single word. Heil hurried to the nearest hospital, where scans revealed he had glioblastoma, the fastest-growing type of brain cancer. Doctors gave him 15 months to live. Surgeons at the City of Hope Medical Center cut a tumor the size of a tennis ball out of the left side of Heil’s brain. The symptoms quickly abated. Heil was back at work just two weeks later, and he even started riding his dirt bike…

As a child growing up in Istanbul in the late 1970s, Ufuk Kocabaş spent his summers swimming, snorkeling and eventually diving around nearby Marmara Island, where his grandfather and other forebears plied the sea as sailors. At age 14, he stumbled upon his first shipwreck, littered with pieces of amphora — an ancient type of storage and transport container — and got an early lesson in proper archaeological practice. “I took some amphora fragments [from the ship] to my sister who was studying at university,” recalls Kocabaş, now head of the Istanbul University Conservation Department. “She told me I shouldn’t have taken them from the site, that I should have left them where they were. At the time, I thought this was stupid. It’s my amphora!” After chiding him, Kocabaş’s…

It was a frigid 17 degrees when Louis “Tom” Freund was descending a three-legged communications tower in a hayfield in Ohio. At 40 feet up, he had a splendid view of the frosted brown stalks stretching to the horizon where the cold earth met a cloudless winter sky. Tom was at the top of his game: At 42, he was running a multimillion-dollar company providing broadband Internet access to rural areas. He’d just remarried and was in superb physical shape, capable of clambering up 250-foot-high towers with 40 pounds of tools on his back, leaving colleagues half his age in his wake. But on this day, Feb. 16, 2009, a weld snapped underfoot — something no amount of experience or physical prowess could have prevented. “I heard a loud ping,…

COMBAT-READY KITCHEN By Anastacia Marx de Salcedo We thank NASA for powdery, vaguely citrus Tang, of course, but when was the last time you saluted the armed forces for the energy bar in your gym bag or the plastic wrap protecting last night’s leftovers? In this engaging, wide-ranging investigation, food writer Salcedo reveals how yesterday’s experiments in feeding combat troops have evolved into the convenience foods likely sitting on your pantry shelves. — GEMMA TARLACH THE MAN WHO WASN’T THERE By Anil Ananthaswamy At the center of this book is a question humans have asked for eons: Who am I? With a thoughtful touch, Ananthaswamy dives in to answer it. He introduces us to people facing radically altered senses of identity: an Alzheimer’s patient whose life narrative erodes relentlessly; a…

Mosquito Misstep? Several readers raised concerns in response to the May issue’s Big Idea column about genetically engineering mosquitoes to resist carrying malaria and dengue fever — or to eliminate the species completely. Here’s an example: Do we never learn? I’m a trained Fish and Wildlife technician and a retired park naturalist. Bats, amphibians and many other animals rely on mosquitoes as a food source, not to mention benefits we may not have even discovered yet. The food web would be badly affected by messing with this vitally important insect. Let’s look at saner, better-thought-out solutions and not create a whole new set of problems. Perhaps developing more effective repellents and clothing for people to wear safely would be one possible venue to slow these deadly diseases. Laurie Eytel Renfrew,…

Conventional wisdom: Sodium consumption causes high blood pressure and heart disease, so we should eat less salt. Contrarian view: Added sugars are more to blame for high blood pressure and heart disease, so we should reduce them instead of sodium. High blood pressure, or hypertension, is the leading cause of America’s No. 1 killer of both women and men: heart disease. Studies have shown that reducing sodium can help control blood pressure, and since the late 1970s, the government and physicians have preached skipping the salt to cut our heart disease risk. But surprisingly, reducing just sodium isn’t all that effective at dropping blood pressure. “Sodium intake is only one — and for most people not necessarily a large — factor in chronic hypertension,” says Hillel Cohen, co-executive editor of…

Try having a thought and documenting it at the same time, and you’ll begin to understand the problem scientists are up against. Halfway into my first marathon, a nagging ache begins to seep from my feet into my ankles. “The wheels are falling off the bus,” I yell as I pass my husband on the sidelines. I’m half-joking, but by the time I hit mile 20, the ache becomes a searing pain. Each time my sneakers strike the trail, the blisters on my toes threaten to rupture. I am in agony. The sound of Billy Joel blasting through my earphones isn’t loud enough to drown out the inner voice that says, “You can’t do this. You’ve failed.” My jog slows to a trot, and soon, I’m hobbling. After the race,…

Trinity College sits in the heart of Dublin, its gray, three-story, neoclassical buildings positioned around lawns and playing fields. At the eastern end of the campus is another gray building, built in 1905 in a rather different style. This is the Fitzgerald Building, or the Physical Laboratory as it is called in deeply engraved letters on the stone lintel. On the top floor is a lecture theater, and in the late afternoon of the first Friday of February 1943, around 400 people crowded onto the varnished wooden benches. According to Time magazine, among those lucky enough to get a seat were “Cabinet ministers, diplomats, scholars and socialites,” as well as the Irish prime minister, Éamon de Valera. They were there to hear the Nobel Prize-winning physicist Erwin Schrödinger give a…

In 1982, when University of Wisconsin anthropologist Karen Strier saw her first northern muriqui in Brazil’s Atlantic Forest, fewer than 1,000 of the critically endangered monkeys remained, scattered across a few remnant patches of forest. At the time, the primate — South America’s largest — was assumed to be inherently aggressive and living in maledominated groups. Strier’s field studies would dispel that myth and reveal the monkeys were egalitarian and peaceful. But her dedication to the muriquis was forged in the forest long before she understood them fully. It was a moment in 1983, early in her first field season, after the group of males and females she was following had adjusted to her presence. IN HER OWN WORDS “I was sitting under a tree on top of this hill,…

In 2010, Discover reported on a theory that brain diseases such as multiple sclerosis (MS) and schizophrenia might have a common source — a virus. Researchers found mounting evidence that we carry this virus in our DNA, like the genes for left-handedness. What’s more, infections such as influenza, picked up from our environment early in life, might be the trigger for these diseases. The theory: Millions of years ago, an ancient human ancestor contracted a retrovirus that inserted its DNA into the host’s reproductive germ cells, passing the viral DNA down the ancestral line. The virus, called human endogenous retrovirus W (HERV-W), codes for a protein that, when activated, sets off an inflammatory cascade in the brain that leads to symptoms. This theory is gaining traction among psychiatrists, especially as a…