Discover Magazine | Agriculture

Can Stuffing Germs up Ferrets Unleash a Human Pandemic?

Fri, 18 May 2012 17:15:00 -0400

The Claim: A lab-concocted strain of ferret flu could become a doomsday weapon or bioterrorist threat.

The Contrarian: Wendy Orent, author of Plague, says the much-hyped fears are unfounded: The new strain presents no danger to humans but reveals a great deal about the transmission of flu.

Ferrets with the flu sneeze and cough like humans.

iStockphoto

Deadly H5N1 avian flu, long entrenched in Asian poultry, has terrified public health experts ever since it killed a Hong Kong boy in 1997. The disease has caused about 340 human deaths in all, raising concerns it might someday unleash a true pandemic. But that has never occurred. The virus is adept at killing chickens and can infect mammals, but it has never spread among them. Until recently no one knew why...

20 Things You Didn't Know About... Allergies

Fri, 18 May 2012 10:15:00 -0400

1. Our immune system may be like those small bands of Japanese “holdout” soldiers after World War II. Not knowing that the war was over, they hid for years, launching guerrilla attacks on peaceful  villages.

2. With our living environment well scrubbed of germs, our body’s immune “soldiers” mistakenly fire on innocent peanuts and cat dander.

5. Most food allergies result from an immune response to a protein. In 2004 a team at Trinity College Dublin tried to counter that reaction by injecting mice with parasites, giving the animals’ immune systems the sort of threat they evolved to fight, thus distracting them from the food proteins.

6. The experiment worked.

7. Excited by such findings, in 2007 British-born entrepreneur Jasper Lawrence flew to Cameroon and walked barefoot near some latrines. His aim was to acquire hookworms, which he hoped would defeat his asthma and seasonal allergies.

8. That worked too.

9. Lawrence has since started a business shipping the parasites worldwide (but not here, where the FDA prohibits it). For $3,000, customers receive up to 35 hookworm larvae...

The Brain: Hidden Epidemic:  Tapeworms Living Inside People's Brains

Tue, 15 May 2012 11:00:00 -0400

Theodore Nash sees only a few dozen patients a year in his clinic at the National Institutes of Health in Bethesda, Maryland. That’s pretty small as medical practices go, but what his patients lack in number they make up for in the intensity of their symptoms. Some fall into comas. Some are paralyzed down one side of their body. Others can’t walk a straight line. Still others come to Nash partially blind, or with so much fluid in their brain that they need shunts implanted to relieve the pressure. Some lose the ability to speak; many fall into violent seizures.

Underneath this panoply of symptoms is the same cause, captured in the MRI scans that Nash takes of his patients’ brains. Each brain contains one or more whitish blobs. You might guess that these are tumors. But Nash knows the blobs are not made of the patient’s own cells. They are tapeworms. Aliens.

A blob in the brain is not the image most people have when someone mentions tapeworms. These parasitic worms are best known in their adult stage, when they live in people’s intestines and their ribbon-shaped bodies can grow as long as 21 feet. But that’s just one stage in the animal’s life cycle. Before they become adults, tapeworms spend time as larvae in large cysts. And those cysts can end up in people’s brains, causing a disease known as neurocysticercosis.

“Nobody knows exactly how many people there are with it in the United States,” says Nash, who is the chief of the Gastrointestinal Parasites Section at NIH...

Image: A human brain overrun with cysts from Taenia solium, a tapeworm that normally inhabits the muscles of pigs. Courtesy of Theodore E. Nash , M.D.

The Hagfish's Special Trick for Warding Off Predators: Thick, Sticky Mucus

Thu, 10 May 2012 17:30:00 -0400

Sharks are superb predators, but even they are no match for the animal kingdom’s most disgusting yet effective defense: the gag-inducing slime of the hagfish.

Hagfish are elusive deep-sea creatures that have mucus-secreting glands positioned all over their long, writhing bodies. Last fall marine ecologist Vincent Zintzen of the Museum of New Zealand Te Papa Tongarewa published a study describing the first-ever observations of hagfish exploiting those glands to ward off predators. He analyzed 500 hours of video from cameras placed in deep waters off the New Zealand coast and found 14 encounters between hagfish and fierce hunters like the seal shark and the conger eel. In every case the hagfish emerged unharmed while the predators fled the scene, gagging on the irritating slime that rapidly expands in seawater and clogs the gills. “It was striking how effective this defense mechanism was,” Zintzen says.

The videos also reveal that at least one species of hagfish can go on the attack...

The Big, Overlooked Factor in the Rise of Pandemics: The Human Vector

Thu, 26 Apr 2012 12:55:00 -0400

“How do you make preparedness sexy?” Dave Daigle asks. A communications expert in disaster readiness at the Centers for Disease Control and Prevention in Atlanta, Daigle created last year’s cheeky Zombie Apocalypse campaign, designed to teach the social media generation how to survive natural disasters and uncontained infectious outbreaks. He never expected the associated Twitter campaign to crash his server and ultimately garner three billion hits. The whole initiative, the most successful in CDC public-relations history, cost taxpayers all of $87—for clip art.

The Zombie Apocalypse campaign instructs you how to prepare for pandemics and catastrophes like hurricanes, tornadoes, and floods. You need a plan. You need flashlights, an all-weather radio, bottled water. You need food you can stock, like peanut butter, canned tuna, and crackers. You need first-aid supplies like bandages, antiseptics, and soap. And you need somewhere safe to stay—a basement room, preferably windowless, where you can hole up for several days until the danger is past.

That style of preparation also resonates with the plots of popular disease-disaster movies, like the recent Contagion. The film presents a fictional virus, a construct devised by Columbia University epidemiologist Ian Lipkin, vectoring its way across the planet, killing millions of the fecklessly unprepared and leaving social havoc and innumerable bodies in its wake. The CDC campaign and the film spring from the same conviction: Since nature can always turn on us, we had better be ready for the consequences.

This kind of preparedness for natural catastrophes makes sense, but for pandemics the idea rings false; unlike the scenario in Contagion, pandemics don’t spring on us like hurricanes. Instead, they are overwhelmingly social phenomena. Mother Nature doesn’t create them; human beings do. We create the settings that allow new, deadly diseases to evolve and invade. Understanding those settings, which can be thought of as disease factories, and taking steps to disrupt them are far better preparation than sending families down to huddle in the basement...

Does Rain Come From Life in the Clouds?

Fri, 20 Apr 2012 18:05:00 -0400

The plane pitches violently as it plows through the milky innards of a cloud bank. A commercial pilot would fly high above these clouds over California’s Sierra Nevada Range, but this 63-foot Gulfstream-1 seems to invite the turbulence. Updrafts grab hold of the aircraft and shove it up even as the pilot noses it down. In the back of the plane, atmospheric chemist Kimberly Prather wears headphones to muffle the roar of the propellers. She steadies herself with a hand on an instrument rack and focuses on the bobbing screen of her laptop. Readings from the clouds spool across it.

Those numbers tell Prather that these winter clouds are cold and heavy, –30 degrees Fahrenheit and just over 100 percent relative humidity. Yet despite being 62 degrees below the freezing point of water, the cloud droplets remain stubbornly liquid. As long as they don’t form ice crystals, these clouds won’t shed more than a few flakes of snow over the Sierras’ 13,000-foot peaks. They are typical clouds, teasers that won’t drop much of anything.

After two hours of flying, though, something changes. The voice of another researcher crackles over Prather’s headset: “Ice!” The plane has entered a cloud layer where suddenly every droplet is frozen. Prather’s instrument—a tangle of metal tubes, wires, and airtight chambers nicknamed Shirley—tick-tick-ticks as its laser blasts apart hundreds of microscopic cloud particles, one by one, that are drawn in from the air outside. The size and composition of each particle flash across Prather’s monitor. The specks at the heart of those ice crystals are high in aluminum, iron, silicon, and titanium, the chemical signatures of dust not from California but from faraway deserts in Asia or even Africa. There’s something else in the crystals too: carbon, nitrogen, and phosphorus, telltale signs of biological cells...

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Image: A high-altitude balloon is readied for a 2011 launch at a NASA facility in New Mexico. It carried microbe collectors up to 120,000 feet.

Gallery | 6 Creepy-Crawlies We Hate But Couldn't Do Without

Wed, 18 Apr 2012 13:55:00 -0400

Click through to view gallery

Plants Repel Bacteria's Assaults by Spying on Their Chatter

Tue, 17 Apr 2012 13:10:00 -0400

Bacteria are quite the talkers. Lying low inside their hosts, they scheme up attacks through coded biochemical messages that are largely imperceptible to the immune systems of plants and animals. But in December researchers published the first evidence that some plants have broken the code, allowing them to listen in on chatter and thwart infection...

Attack of the Flying, Invasive Carp

Thu, 12 Apr 2012 10:20:00 -0400

Ending through corn and  soybean fields southwest of Chicago, the Illinois River eventually comes to the sleepy little town of Havana, Illinois. On the east bank of the river, the populated side, there is a field station run by the Illinois Natural History Survey. For decades now, INHS biologists in aluminum skiffs have scooted up and down the thinly wooded banks, monitoring local fish—these days, catching, recording and releasing approximately 150,000 of them a year. The local species are small and nondescript for the most part; their behavior is unremarkable. Probably the most colorful thing about these fish is their names: gizzard shad, bigmouth buffalo, largemouth bass, bluntnose minnow—hand-hewn names from America’s heartland.

In the mid-‘90s, though, the lazy stretch of river around Havana was roiled by the invasion of two species of Asian carp, the bighead carp and its flamboyant cousin, the silver carp. Imported from China during the 1970s, the carp escaped their ponds in the South, migrated up the Mississippi River, and spread into tributaries like the Illinois. “They puttered along for a few generations,” says Duane C. Chapman, the top Asian carp expert for the U.S. Geological Service, “and then they reached an exponential growth phase.” A quirk of silver carp behavior—an exaggerated startle response, causing them to leap from the water when boats approached—revealed their enormous, unexpected populations in the rivers of the Midwest. Along La Grange Reach, as this section of the Illinois is called, routine monitoring tasks took a dangerous turn. Today, the biologists have to measure the local species amid a glut of flying aliens.

You’re sitting in the kill zone,” Thad Cook remarked to me, as the skiff pulled away from the launch site. Cook, director of the INHS station, was driving. He sat behind a low shield in the stern, but the visitor’s chair beside him was exposed. I stood up nervously, holding onto a strut. I recalled reading about a woman who nearly died while riding a jet-ski near Peoria, upstream from Havana, in 2004. She was knocked unconscious by a silver carp and tumbled into the river. “We’re at ground zero,” Cook warned, smiling. “The carp don’t wax and wane here.” In a video I’d watched on the Internet, a water-skier wearing a football helmet laughs hysterically as he is towed through a fusillade of carp...

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Hot Science: The Best New Science Culture

Mon, 09 Apr 2012 12:15:00 -0400

Frozen Planet Discovery
It took 4 years, 38 sled dogs, 12 reindeer, 28 helicopters, and 840 hours trapped in blizzards for dedicated (and resourceful) camera crews to film the epic new nature documentary Frozen Planet. This seven-part special showcases the ecosystems and inhabitants of Earth’s most frigid climes with the same expansive, lush cinematography seen in Planet Earth and Life. All three are collaborations between the BBC and the Discovery Channel (not connected with DISCOVER magazine). With footage of frolicking polar bear cubs, mesmerizing time-lapse video of a frozen waterfall thawing in spring, and an up-close look at how rising temperatures are ravaging those environments, Frozen Planet has something for everyone—even those whose tastes run more to sitcoms than documentary. The ever-sonorous Alec Baldwin (30 Rock) narrates the American version of the show. Sundays at 8 p.m. ET/PT on the Discovery Channel.
—Mary Beth Griggs

Touch  Fox
 Kiefer Sutherland (24) returns to TV as a widower whose mute, autistic son, Jake, is a mathematical savant. In the numerical detritus of everyday life—phone numbers, dates, times—Jake can sense patterns invisible to others. He uses these patterns to predict—and with his father’s help, propel people toward—events that pull seemingly unrelated people together...

Image: Chadden Hunter

Superfreak of Evolution: The Lizard With a Humanlike Placenta

Mon, 09 Apr 2012 11:10:00 -0400

Trachylepis ivensi nurtures its fetus much like humans do.

In central Africa, an unassuming little lizard has evolved a spectacular and oddly human feature of gestation: a complex placenta. It is the first time that scientists have observed such an advanced version of this organ connecting the fetus to the womb in nonmammals.

Biologist Alexander Flemming made the anatomical find, announced late last year, while sorting through specimens at the Port Elizabeth natural history museum in South Africa. Flemming and his collaborator, Daniel Blackburn, knew that about 20 percent of lizards give birth to live young, but finding the placenta came as a shock...

Image: Dr. Philipp Wagner

Gallery | 7 Animals That Harnessed Nanotechnology Long Before Humans

Tue, 03 Apr 2012 13:20:00 -0400

Click through to view gallery

How Mosquitoes Survive  in a Downpour

Wed, 14 Mar 2012 11:10:00 -0400

Georgia Institute of Technology mechanical engineer David Hu was sitting on the porch with his infant son when a large mosquito bite appeared on the baby’s forehead. It was pouring out, and Hu began wondering how the insect survived the impact of the drops. “A mosquito weighs only a couple milligrams, and the drops are up to 50 times heavier,” he says. “It’s like a person being hit by a bus”...

Image: iStockphoto

Destination Science: The Natural World Outside Disney World

Mon, 12 Mar 2012 18:40:00 -0400

Unpaved Orlando
Where: Central Florida
 What: Pristine wilderness in the shadow of America’s theme park capital

Orlando is famous as the family-fun city that Disney built, but it has quietly developed a secret second identity as a jumping-off spot to some of the most pristine wilderness in Florida. Sadly, the bulk of the 50 million-plus visitors who converge on this tourist megalopolis every year, spending hours creeping along congested highways from hotels to theme parks, probably never realize that the other, wilder Florida lurks just an exit away. When I passed through recently with my daughters en route to a family reunion, we were able to explore this hidden Orlando, where tropical ecology is the prime attraction. It was a relaxing antidote to the hyperstimulating theme park experience: no crowds, no merchandise booths, no imitation castles, and the only mouse ears in sight belong to Podomys floridanus, the Florida mouse.

Photo: Look Die Bildagentur der Fotografen GMBH/ALAMY

Of Mice and Men and Medicines

Fri, 24 Feb 2012 09:55:00 -0500

You won’t find more mentally ill mice per square mile anywhere than in Bar Harbor, Maine. Mice who seem anxious or depressed, autistic or schizophrenic—they congregate here. Mice who model learning disabilities or anorexia; mice who hop around as though your hyperactive nephew had contracted into a tiny fur ball; they are here too. Name an affliction of the human mind, and you can probably find its avatar on this sprucy, secluded island.

The imbalanced mice are kept under the strictest security, in locked wards at the Jackson Laboratory, a nonprofit biomedical facility internationally renowned for its specially bred deranged rodents. Every day trucks carry away boxes and boxes of them for distribution to psychiatric researchers across the nation.

There are no visiting hours, because strangers fluster the mice and might carry in contagious diseases. The animals are attended only by highly qualified caregivers, people like neuroscientist Elissa Chesler. Sitting in her airy Jackson Lab office, accessible to germy and perturbing strangers, Chesler clicks open a series of photographs from a type of mouse personality test on her computer screen. The first picture shows a mouse sleeping on a nestlet, a stiff, square bed of compressed cotton. Mice typically gnaw vigorously at the cotton, shredding it to make soft igloos for sleeping and staying warm. The second image shows a mouse that has propped his nestlet against a wall, forming a makeshift lean-to. “When I see this guy, I’m thinking anxiety,” says Chesler, whose research delves into the genetics of stress. “This design isn’t trapping a lot of heat, but he’s secure under there.”

She smiles as she clicks open the last photo. “And here we have the ‘I can’t deal with it’ mouse,” she says. The image shows a mouse asleep, with his rigid nestlet balanced on his back. Personality, Chesler maintains, can be read from these nestlet styles more clearly than from a test of forced swimming or bar pressing...

Here’s Looking at You, Kid

Tue, 21 Feb 2012 15:45:00 -0500

Staring off the page is the eye of a water flea, a largely transparent crustacean that can reach half an inch in length. Its intricate eye—and it has only one—is a clue to the creature’s overall complexity: Last year scientists found that it has 30,907 genes, about 5,000 more than humans have. This micrograph of a live specimen was named an image of distinction in last year’s Nikon Small World competition. “I capture organisms as realistically as possible,” says photographer Wim van Egmond, “but the microworld is so unknown that the result is almost like abstract photography.”

Image: Nikon Small World

Gallery | The Grinches That Stole Valentine's Day: Creatures That Say No to Sex

Tue, 14 Feb 2012 09:25:00 -0500

Click through to view gallery

The Spider Assassin That Acts Like Prey and Cloaks Itself With Wind

Mon, 06 Feb 2012 14:00:00 -0500

A good predator must be as cunning as it is strong, especially when its prey can turn the tables and kill it. The assassin bug has learned this well, becoming a master of deception in its hunt for spiders. Last year biologist Anne Wignall from Australia’s Macquarie University discovered that the bug lures food by strumming webs with its legs, mimicking the vibrations of a trapped fly. Now she has found that the insects exploit the weather by stalking spiders in the wind...

How Did LEGO Become More About Limits Than Possibilities?

Fri, 03 Feb 2012 09:30:00 -0500

No matter what you do with it, it'll still look like Hogwarts.

Rip open that new LEGO set and your mind races at the possibilities! A simple repertoire of piece types, and yet you can build a ninja boat, a three-wheeled race car, a pineapple pizza, a spotted lion… The possibilities are limited only by your creativity and imagination. “Combine and create!”—that was the implicit war cry for LEGOs.

So how, I wonder, did LEGO so severely lose its way? LEGO now fills the niche that model airplanes once did when I was a kid, an activity whose motto would be better described as “Follow the instructions!” The sets kids receive as gifts today are replete with made-to-order piece types special to each set, useful in one particular spot, and often useless elsewhere. And the sets are designed for constructing some particular thing (a Geonosian Starfighter, a Triceratops Trapper, etc.), and you—the parent—can look forward to spending hours helping them through the thorough yet thoroughly exhausting pages.

LEGO appears to be doing very well for itself, and there’s no shame in helping to revolutionize model-building (and there’s an elegance to snapping together one’s models rather than gluing them together). But one has to wonder whether, at some deep philosophical level, the new LEGOs really are LEGOs at all, as they’re no longer the paragon of creative construction they once were and with which they’re still associated.

In fact, as I was bemoaning my kids’ LEGOs with the Guardian's Roger Highfield (and later with WIRED's Samuel Arbesman), it struck me that I have such data on LEGOs...

Discover Magazine | Agriculture

Can Stuffing Germs up Ferrets Unleash a Human Pandemic?

20 Things You Didn't Know About... Allergies

The Brain: Hidden Epidemic:  Tapeworms Living Inside People's Brains

The Hagfish's Special Trick for Warding Off Predators: Thick, Sticky Mucus

The Big, Overlooked Factor in the Rise of Pandemics: The Human Vector

Does Rain Come From Life in the Clouds?

Gallery | 6 Creepy-Crawlies We Hate But Couldn't Do Without

Plants Repel Bacteria's Assaults by Spying on Their Chatter

Attack of the Flying, Invasive Carp

Hot Science: The Best New Science Culture

Superfreak of Evolution: The Lizard With a Humanlike Placenta

Gallery | 7 Animals That Harnessed Nanotechnology Long Before Humans

How Mosquitoes Survive  in a Downpour

Destination Science: The Natural World Outside Disney World

Of Mice and Men and Medicines

Here’s Looking at You, Kid

Gallery | The Grinches That Stole Valentine's Day: Creatures That Say No to Sex

The Spider Assassin That Acts Like Prey and Cloaks Itself With Wind

How Did LEGO Become More About Limits Than Possibilities?

Top 100 Stories of 2011: #63: How Many Species Inhabit the Earth?

Top 100 Stories of 2011: #74: Meet the Megavirus

Top 100 Stories of 2011: #18: Genome of Vegetables Remains Active After You Eat Them

Top 100 Stories of 2011: #85: Meet the Grazing Hominid

Top 100 Stories of 2011: #49: Arsenic-Based Life Shakes Up Science (Again)

Top 100 Stories of 2011: #68: Tools Imply Early African Exodus

Discover Magazine | Agriculture

Can Stuffing Germs up Ferrets Unleash a Human Pandemic?

20 Things You Didn't Know About... Allergies

The Brain: Hidden Epidemic: Tapeworms Living Inside People's Brains

The Hagfish's Special Trick for Warding Off Predators: Thick, Sticky Mucus

The Big, Overlooked Factor in the Rise of Pandemics: The Human Vector

Does Rain Come From Life in the Clouds?

Gallery | 6 Creepy-Crawlies We Hate But Couldn't Do Without

Plants Repel Bacteria's Assaults by Spying on Their Chatter

Attack of the Flying, Invasive Carp

Hot Science: The Best New Science Culture

Superfreak of Evolution: The Lizard With a Humanlike Placenta

Gallery | 7 Animals That Harnessed Nanotechnology Long Before Humans

How Mosquitoes Survive in a Downpour

Destination Science: The Natural World Outside Disney World

Of Mice and Men and Medicines

Here’s Looking at You, Kid

Gallery | The Grinches That Stole Valentine's Day: Creatures That Say No to Sex

The Spider Assassin That Acts Like Prey and Cloaks Itself With Wind

How Did LEGO Become More About Limits Than Possibilities?

Top 100 Stories of 2011: #63: How Many Species Inhabit the Earth?

Top 100 Stories of 2011: #74: Meet the Megavirus

Top 100 Stories of 2011: #18: Genome of Vegetables Remains Active After You Eat Them

Top 100 Stories of 2011: #85: Meet the Grazing Hominid

Top 100 Stories of 2011: #49: Arsenic-Based Life Shakes Up Science (Again)

Top 100 Stories of 2011: #68: Tools Imply Early African Exodus

The Brain: Hidden Epidemic:  Tapeworms Living Inside People's Brains

How Mosquitoes Survive  in a Downpour