PDF Discover Magazine October 2016 | Science of Aging PDF Download

PDF Discover Magazine October 2016 | Science of Aging PDF Download by Various (Author) Discover October 2016 Issue Science of Aging: does DNA hold the secrets to longevity? The power of one brain; drilling to doomsday; the science behind your credit score; to planet 9... and beyond; crowdsourcing cancer research

SPACE MEDICINE To Planet and Beyond! p.70 Crowdsourcing Cancer Research p.24 SCIENCE FOR THE CURIOUS ® SCIENCE of AGING Does DNA hold the secrets to longevity? p.28 PLUS The Power of One Brain Drilling to Doomsday The Science Behind Your Credit Score p.18 p.50 p.42 BONUS ONLINE CONTENT CODE p.5 A B LL Bu ig -NE tt ge W on r s s o N act r nt Co “My friends all hate their cell phones… I love mine!” FR EE Car Charg er Here’s why Say good-bye to everything you hate about cell phones Say hello to the ALL-NEW Jitterbug Flip “Cell phones have gotten so small, I can barely dial mine.” Not the new Jitterbug® Flip It features a larger keypad for easier dialing It even has a larger display so you can actually see it “I had to get my son to program it.” Your Jitterbug Flip set-up process is simple We’ll even program it with your favorite numbers “I tried my sister’s cell phone… I couldn’t hear it.” The Jitterbug Flip is designed with a powerful speaker and is hearing aid compatible Plus, there’s an adjustable volume control “I don’t need stock quotes, Internet sites or games on my phone I just want to talk with my family and friends.” Life is complicated enough… The Jitterbug Flip is simple “What if I don’t remember a number?” Friendly, helpful Operators are available 24 hours a day and will even greet you by name when you call “My cell phone company wants to lock me in a two-year contract!” Not with the Jitterbug Flip There are no contracts to sign and no penalty if you discontinue your service Order now and receive a FREE Car Charger for your Jitterbug Flip – a $25 value Call now! 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To make us all smarter ON THE COVER BY ADAM PIORE To Planet and Beyond! p.70 42 Drilling to Doomsday Beneath the Gulf of Mexico lies evidence of one of Earth’s most cataclysmic events Now, experts are getting their closest look yet BY ERIC BETZ 50 Weapons of Math Destruction Sure, credit scores are important, but they hold more sway than you’d think And in many cases, that can be a very bad thing BY CATHY O’NEIL Crowdsourcing Cancer Research p.24 Science of Aging p.28 The Power of One Brain p.18 Drilling to Doomsday p.42 Science Behind Your Credit Score p.50 Cake photo: William Zuback/Discover; DNA candle: Jay Smith; background: Melis/Shutterstock COLUMNS & DEPARTMENTS EDITOR’S NOTE Chasing Longevity Living to 100 takes a stroke of genetic luck and a dose of resilience 24 BIG IDEA Fighting Cancer With Data THE CRUX How experts plan to give the Ignorosphere some love, an update on surgeon Anthony Atala’s work on 3-D bioprinting, we add to our blog family and more! 18 PROGNOSIS A Mind in Time Researchers are spending some quality one-on-one time with patients’ brains The results could steer the course for future clinical treatment BY ADAM HADHAZY MARK GARLICK Lady Macbeth’s book and try washing your hands It works, and neuroscience backs it up BY MALLORY LOCKLEAR 22 MIND OVER MATTER Think Outside the Brain Cracking the human genome means doctors can now personalize cancer treatments But not without teamwork and a whole lot of computing power BY AIMEE SWARTZ 70 OUT THERE 74 NOTES FROM EARTH The Judas Fish In Montana, the invasive lake trout is choking native fish populations With a secret weapon, ecologists are finally turning the tide BY JANINE LATUS 78 HISTORY LESSONS A Profile of Plague The deadly pestilence of old is still around, and scientists are learning about its past and future BY HILLARY WATERMAN To Planet — and Beyond! 82 Past the celestial body formerly known as a planet, i.e., Pluto, astronomers are continuing their hunt for the elusive Planet BY COREY S POWELL Forget your stereotypes, there’s more to these winged mammals of the dark than vampire lore BY GEMMA TARLACH 20 THINGS YOU DIDN’T KNOW ABOUT … BATS 57 OUT THERE SPECIAL BONUS SECTION Crucial tips for your 2017 eclipse planning, the amateur astronomer who beat NASA to the punch with his observations of Saturn, and how one legendary meteorite hunter has turned his eyes from the ground to the skies Feeling guilty? Take a page from October 2016 DISCOVER Discover SCIENCE FOR THE CURIOUS Editor's Note ® BECKY LANG Editor In Chief DAN BISHOP Design Director Chasing 100, With Cellular Mechanics Resilience For those who live into their 90s and past 100, it’s a crucial part of the equation, as you’ll find out in our cover story (see page 28) It’s grounded them through wars, the Depression, civil unrest and their individual daily stressors The notion of resilience has been running through my head lately, as I’ve watched footage from the aftermath of police shootings and terror attacks What does it take to prevail through that kind of pain, both on an individual basis and across society? I would argue that resilience in the face of today’s social upheaval is so grounded, it’s in our bones, it’s in the very structure of our cells It’s those cellular mechanics — the clockwork — that appear to drive how we age The notion of a timekeeper is at the heart of some researchers’ work to crack the code of aging For most of us, the very process of aging eventually dooms us to disease But for those of us who live beyond 100, it’s as if the cellular clocks have slowed down In addition, scientists have found that how these centenarians live makes a difference A safety net of friends and family Plenty of walking Real food Experiences throughout their lives will shape how their genes function In the quest for longevity, here’s to a big dose of resilience and a way to slow down that cellular ticktock EDITORIAL KATHI KUBE Managing Editor GEMMA TARLACH Senior Editor BILL ANDREWS Senior Associate Editor ERIC BETZ Associate Editor LACY SCHLEY Assistant Editor DAVE LEE Copy Editor ELISA R NECKAR Copy Editor AMY KLINKHAMMER Editorial Assistant BRIDGET ALEX AAAS Mass Media Fellow Contributing Editors DAN FERBER, TIM FOLGER, LINDA MARSA, STEVE NADIS, ADAM PIORE, COREY S POWELL, JULIE REHMEYER, ERIK VANCE, STEVE VOLK, PAMELA WEINTRAUB, JEFF WHEELWRIGHT, DARLENE CAVALIER (SPECIAL PROJECTS) ART ERNIE MASTROIANNI Photo Editor ALISON MACKEY Associate Art Director DISCOVERMAGAZINE.COM CARL ENGELKING Web Associate Editor NATHANIEL SCHARPING Web Staff Writer Bloggers MEREDITH CARPENTER, LILLIAN FRITZ-LAYLIN, JEREMY HSU, REBECCA KRESTON, JEFFREY MARLOW, NEUROSKEPTIC, ELIZABETH PRESTON, SCISTARTER, CHRISTIE WILCOX, TOM YULSMAN ADVERTISING STEVE MENI Advertising Sales Manager 888 558 1544 smeni@discovermagazine.com Rummel Media Connections KRISTI RUMMEL Consulting and Media Sales 608 435 6220 kristi@rummelmedia.com MELANIE DECARLI Marketing Architect BOB RATTNER Research DARYL PAGEL Advertising Services KALMBACH PUBLISHING CO CHARLES R CROFT President STEPHEN C GEORGE Vice President, Content DANIEL R LANCE Senior V.P., Sales & Marketing JAMES R MCCANN Vice President, Finance NICOLE MCGUIRE Vice President, Consumer Marketing JAMES SCHWEDER Vice President, Technology ANN E SMITH Corporate Advertising Director MAUREEN M SCHIMMEL Corporate Art Director KIM REDMOND Single Copy Specialist MIKE SOLIDAY Art and Production Manager SUBSCRIPTIONS In the U.S., $29.95 for one year; in Canada, $39.95 for one year (U.S funds only), includes GST, BN 12271 3209RT; other foreign countries, $44.95 for one year (U.S funds only) Feel free to send comments and questions to editorial@discovermagazine.com editorial@discovermagazine.com 21027 Crossroads Circle, Waukesha, WI 53186 facebook.com/DiscoverMag twitter.com/DiscoverMag plus.google.com/+discovermagazine DISCOVERMAGAZINE.COM 800 829 9132 Outside the U.S and Canada: 813 910 3616 Customer Service: Discover@customersvc.com Digital: Discover.Digital@customersvc.com Back Issues: Discover.SingleCopy@customersvc.com EDITORIAL INQUIRIES CONNECT WITH US CUSTOMER SALES & SERVICE WILLIAM ZUBACK/DISCOVER Becky Lang THE CRUX The Latest Science News & Notes LIFE’S LIMITS They might be tiny, but these microscopic plankton fossils, called planktonic foraminifera, are a nearly continuous 65 million-year record of life on Earth University of Southampton evolutionary ecologist Thomas Ezard and his team compared the collection’s number of species with markers of ocean temperature and sediment composition during their life spans Data revealed a broader picture of how environmental variations affect biodiversity Cardiff University earth scientist Paul Pearson took this composite photo of Ezard’s subjects, each less than a millimeter wide, with a scanning electron microscope  ERNIE MASTROIANNI; PHOTO BY PAUL PEARSON/CARDIFF UNIVERSITY October 2016 DISCOVER THE CRUX Destination: Ignorosphere All aboard, scientists studying climate change Ever heard of the Ignorosphere? It’s what scientists have jokingly nicknamed the mesosphere, the third atmospheric layer from Earth’s surface It’s always been tough for researchers to access and so has been largely ignored But that’s about to change, thanks to work done by Project PoSSUM (Polar Suborbital Science in the Upper Mesosphere) While unmanned rockets, satellites and balloons — most notably NASA’s AIM satellite — have taken images of and collected data from the layer in the past, new suborbital vehicles will make it possible to send actual human scientists to the mesosphere to study noctilucent (NLC) clouds These ragged, spidery clouds began appearing in the late 1800s, and their increasing frequency and geographic spread are believed to be a marker for climate change They’ve been difficult to study, however: They’re too high for detailed data collection via ground-based instruments, balloons or aircraft, and too low for orbital satellites The complex equipment that can measure fine-scale changes in the clouds’ composition needs a human operator Noctilucent clouds Project PoSSUM’s executive director, Jason Reimuller, says suborbital rocket planes are scheduled to launch from Alaska in 2018 They’ll head into the Ignorosphere with scientific instruments like the ones pictured here  CAROLINE BARLOTT Making Manned Flights Possible PoSSUM plans to use XCOR Aerospace’s suborbital rocket plane Lynx; two people fit in its flight pod Unlike commercial planes, which can use the lower atmosphere’s oxygen to give their fuel systems a boost, suborbital rocket planes use liquid oxygen tanks to compensate for the thin air and get the thrust they need DISCOVERMAGAZINE.COM CLOUDS: JAN ERIK PAULSON/ NASA EARTH OBSERVATORY Extra Thrust Required Thermosphere +4.6 MINUTES During the 30-minute round-trip flight, PoSSUM personnel will only have about four minutes to collect data MICROGRAVITY ENVIRONMENT 328,000 feet 350,000 325,000 300,000 275,000 ENGINES OFF 190,000 feet Glide and circle 250,000 225,000 200,000 175,000 150,000 Horizontal landing Stratosphere Horizontal takeoff 125,000 Troposphere Powered ascent MAX AIRSPEED: MACH 2.9 50,000 Altitude (feet) Coast upward Mesosphere +3 MINUTES Re-entry 100,000 75,000 25,000 These rocket engines can be used for thousands of flights, potentially making scientific ventures more affordable LYNX PLANE, FLIGHT PLAN AND ENGINE TEST: XCOR; EXPERIMENTS FROM LEFT: PROJECT POSSUM; ZOLTAN STERNOVSKY; GERALD LEHMACHER Rocket engine test PoSSUM’s Technology In addition to shooting traditional video of the NLC clouds, an automated infrared imager will record a layer of molecules — the airglow — that sits just above them The images will give experts a better idea of the mesosphere’s overall structure As the vehicle passes through clouds, a shoebox-sized instrument will capture air to compare carbon dioxide and nitric oxide levels with surface levels An aerosol sampler will collect fine particles from the atmosphere, believed to be leftover meteor bits, which may explain how the clouds form in the first place The Mesosphere Clear Air Turbulence instrument will use pressure data to calculate temperatures that will help determine how the clouds grow October 2016 DISCOVER THE CRUX The Lure of the Landfill Birds give up on migrating and gorge on garbage instead trips from their permanent nests to landfills dozens of miles away — something previously unheard of some European birds would vanish Aldina Franco and a team from after summer and reappear in the University of East Anglia spring A hunter in Mecklenburg, followed the birds as they feasted Germany, killed a white stork that behind dump trucks dropping already had an African projectile off discarded meat at a landfill lodged in its neck Nearly Incredibly, the steady supply has two centuries later, European allowed stork populations to researchers are trying to explain increase tenfold since the 1980s a new phenomenon: Why have “The landfill food enables the many storks stopped migrating? storks to raise a larger number of Roughly 14,000 of the fairchicks per nest,” Franco says weather fowl in Portugal have The storks are just one of many given up flying south In a recent The easy access to food is just too enticing for white storks in species shifting their migration study published in the journal Portugal The birds have stopped migrating in favor of feasting at garbage sites like this one patterns because of human behavior Movement Ecology, conservation And these birds might soon reroute ecologists used GPS tags to track again: The European Union recently revised landfill rules so that 17 of those white storks through their normal migration period food waste is handled under cover That could leave the storks to figure out why looking elsewhere for their junk-food fix  ERIC BETZ Instead of heading to sub-Saharan Africa, the birds made regular 10 DISCOVERMAGAZINE.COM Huge selection! Please give order code Z096 Books • Magazines Globes & Maps • Posters Downloads • And more! com MyScienceShop P27902 UNIVERSITY OF EAST ANGLIA In 1822, a well-placed arrow solved the mystery of why SPECI A L BONUS SECTION OUT THERE To Planet — and Beyond! Our familiar solar system still hides some of the universe’s biggest mysteries → Some astronomers have a knack for making it seem like humans have truly become masters of the universe They built the Gaia space observatory, currently scrutinizing a billion stars to create the definitive map of the Milky Way They detected ripples in space and time caused by black holes crashing into each other in a distant galaxy They have analyzed the afterglow of the Big Bang — the 70 DISCOVERMAGAZINE.COM very beginning of existence! — to measure the precise amount of matter and energy in the entire universe And then there is astronomer Mike Brown of Caltech, always ready to deliver a dose of humility His specialty is exploring the outer reaches of our solar system, a mere 1/1,000th the distance to the sun’s nearest star, and finding it full of shadowy unknowns Brown is most famous as the guy who discovered that Pluto is surrounded by a whole population of related objects It was a revelation that prompted the International Astronomical Union to reclassify the former ninth planet as a “dwarf planet” and Brown to christen himself “@plutokiller” on Twitter Recently, Brown and his colleague Konstantin Batygin made headlines again, this CALTECH/R HURT (IPAC) BY COREY S POWELL TOP: CALTECH/R HURT (IPAC)/WORLDWIDE TELESCOPE BOTTOM: PATRICK T FALLON time by reporting convincing evidence of a true Planet — a world some 5,000 times the mass of Pluto, orbiting even farther from the sun Perhaps the most striking thing about Planet is not that it (probably) exists, but that nobody has found it yet: a giant body, circling right in our celestial backyard, sight unseen Masters of the universe? Ha We don’t even know how many planets are in our own solar system Brown likens his fumbling investigations of the realm beyond Pluto to the journeys of 16th-century European navigators “Think of it the way you would if you were jumping on a ship going across the ocean and didn’t know what was going to be around the next corner,” he says “I have some ideas of what might be there, but right now it’s really still a ‘there be dragons’ world that we don’t know anything about.” SLOWLY, INTO THE DARK Exploring the outer solar system has always been a halting, painstaking process Uranus, the first planet discovered in the modern era, was probably spotted by Greek astronomer Hipparcos in 128 B.C but not recognized for what it is until William Caltech’s Mike Brown (left) and Konstantin Batygin announced evidence — not proof — of a ninth planet in the solar system The aligned orbits of the six most distant solar system objects (purple) suggest Planet 9’s path Perhaps the most striking thing about Planet is not that it (probably) exists, but that nobody has found it yet: a giant body, circling right in our celestial backyard, sight unseen Herschel recorded it in 1781 Galileo apparently observed Neptune in 1613 but mistook it for an ordinary star; the planet wasn’t identified for real until 1846 Despite an intensive search for a hypothetical Planet X, pursued with fanaticism by wealthy eccentric Percival Lowell, it took another 84 years after Neptune’s discovery before Clyde Tombaugh discovered Pluto Then 75 more years passed before Brown located the distant dwarf planet Eris and showed that Pluto is not alone As Brown explains, there is a simple reason for the snail’s pace of discovery: “It’s a big solar system, and things get faint fast!” Solar illumination gets dimmer with the square of distance from the sun, and then any light reflected off a distant body likewise dims with the square of its distance from Earth Put the two effects together, and the consequences are daunting If you moved Pluto twice as far from the sun, its apparent brightness would decrease by to the 4th power — a factor of 16 Brown and a handful of colleagues have now pretty well scanned the zone around Pluto, out to around billion miles from the sun, for large objects A frozen ball known as V774104, currently the most distant solar system object known, is twice that far Go just a little deeper, though, and all kinds of things could be circling about, invisible to even the best telescopes For now, the evidence for Planet comes solely from its gravity, not from its light Starting about a decade ago, astronomers noticed odd patterns in the distant solar system Brown and Batygin were especially struck by the orbits of six of the most extreme objects in the Kuiper Belt (the population of outer objects that includes both Pluto and Eris), all of which cluster on one side of the sky They deduced that a large planet, roughly 10 times the mass of Earth, was lurking on the other side of the sun, its gravitational pull sweeping any smaller stuff out of the way The pattern of clustering indicated a likely orbit for Planet The fact that nobody had noticed it yet offered another clue: The planet must be on the darkest, farthest part of its looping path, possibly 100 billion miles away That still leaves a lot of sky to examine To visually track down his putative Planet 9, Brown is requesting 20 nights of observing time on the Subaru telescope in Hawaii, the only large instrument with a wide enough field of view to practically pull off October 2016 DISCOVER 71 SPECI A L BONUS SECTION such a search Even if he gets his observing time (there’s a lot of competition), the project will take at least a year and a half Brown has learned to be philosophical about these things “There’s always a chance that the six times you’re looking for Planet 9, it happens to align with a star and you miss it,” he says, “but eventually we’ll find it, and then we’ll study it to death.” THE GREAT BEYOND An important lesson from the discovery of Eris and the rest of the Kuiper Belt is that Planet is certainly not alone Astronomers now realize that the formation of the solar system was a messy, chaotic process that ejected all kinds of bodies out to the far fringes Today, there are four giant outer planets Planet 9, if it exists, is most likely a stillborn fifth giant planet, a smaller version of Neptune that got sent off on a very different evolutionary track As Brown points out, it’s perfectly possible that six, seven or even more giant planets started to form before some of them were ejected It is even more likely that smaller bodies — Mars size? Moon size? — are floating around on the fringes “There’s a ton of stuff out there,” Brown says And could Subaru spot a moon-size thing at a Planet 9-like distance? “Nope, nope, nope Not a chance.” Inner solar system The future Large Synoptic Survey Telescope (seen in this artist’s conception) could find even more planets in its full-sky scans One way to extend human vision is to look for heat rather than light Truly giant planets would retain a lot of thermal energy from the time of their formation, and therefore could show up in telescopes tuned to infrared rays or even colder millimeter waves The WISE space telescope did a sky survey and found nothing, ruling out distant versions of Jupiter or Saturn But Planet would be too small and cool to show up in WISE’s detectors Brown and the other outer explorers are much more jazzed about the Large Synoptic Survey Telescope (LSST), currently under construction atop Cerro Pachón in Chile Starting in 2023, the LSST will perform extremely sensitive, repeated scans of the full night sky It should eventually spot hundreds or even thousands of bodies out to the distance of Planet Perhaps that bounty will include colder versions of Pluto, or a weird deep-freeze analog Outer solar system of Mars The orbits of all those objects, in turn, could indirectly reveal the presence of even more distant worlds “LSST will be great,” Brown gushes “And I guarantee you, we’ll see patterns we didn’t anticipate Then we’ll have to start looking to see what’s causing those other patterns.” Such bootstrapping will quickly hit a wall, however There is no greater survey telescope planned after LSST — “a scary thing to think about,” Brown says — but we already know that the solar system keeps going far beyond that instrument’s limits The Oort Cloud, a loosely bound flock of dormant comets, extends to at least 100 times Planet 9’s distance from the sun There could be planet-size objects lurking out there as well We have no way to see them, no way to detect them, not even any ideas on the drawing board about how to find them When it comes to our celestial backyard, mystery — not mastery — is the name of the game “It’s a big unknown,” Brown says “I would love to just get in a spaceship and drive around the outer solar system, taking a look at this object and this object and seeing what’s really going on out there.” D Corey S Powell, a contributing editor of Discover, also writes for the magazine’s Out There blog Follow him on Twitter: @coreyspowell Post–Kuiper Belt objects Inner extent of Oort Cloud The solar system’s a big place More planet-size objects could lurk at Planet 9’s impressive distance from the sun, and no one knows what oddities might exist 100 times farther out in the enormous Oort Cloud 72 DISCOVERMAGAZINE.COM TOP: TODD MASON, MASON PRODUCTIONS INC./LSST CORPORATION BOTTOM: NASA/JPL-CALTECH/R HURT (SSC-CALTECH), ADAPTED BY COREY S POWELL OUT THERE Join Discover magazine in Iceland! Fire, Ice, & Aurora Adventure Explore the fascinating and diverse geology of Iceland on this trip of a lifetime — and marvel at magnificent auroral displays under dark northern skies The editors of Discover and Astronomy magazines, working with TravelQuest International, have put together a wonder-filled travel itinerary that features: Discover SCIENCE FOR THE CURIOUS ® M AG A Z I N E MARCH 18-25, 2017 • nights of aurora viewing from the optimal observation location: Iceland, blessed with frequent and spectacular displays under vast night skies • Iceland’s remarkably varied geology of fire — active volcanoes, steaming geysers, and natural hot springs — and ice — magnificent glaciers and sparkling icefields P28835 • Lively discussions of starry skies and northern lights, and tips on nighttime photography techniques For more information, visit DiscoverMagazine.com/trips-tours Notes From Earth The Judas Fish In Montana’s glacial lakes, biologists deploy an unusual weapon to defend native bull trout against an invader BY JANINE LATUS → 74 DISCOVERMAGAZINE.COM Lake trout were introduced for sport fishing in western waterways, but they’ve outcompeted native species “We have to stop this ecological catastrophe, or Glacier’s native fishes will be lost for future generations.” USGS research ecologist Clint Muhlfeld is part of National Park Service efforts to restore native bull trout in Glacier National Park encouraging anglers to take as many of the fish as they can catch But on Quartz Lake, Muhlfeld and his team worked with the National Park Service to deploy a weapon they believe will greatly improve the bull trout’s odds: the Judas fish The crews create these Judas fish by scooping up adult lake trout, cutting them open and inserting tracking devices Then they sew the live fish shut and release them back into the lake In autumn, the crews spend weeks clustered around the woodstove in a cabin on Quartz Lake, heading out at night on the nearly frozen lake, listening through headphones for the ping of sonic telemetry to track the Judas fish It’s a 900-acre lake, yet over a two-week period around Halloween, all the adult lake trout gather at night at the fish equivalent of a giant singles bar, at the base of an avalanche chute where cobble and boulders provide safe havens for them to spawn The Judas fish, living up to its biblical namesake, betrays the exact position That’s when the biologists drop the nets and pull them in, hand-over-hand to the slaughter TOP: JOEL SARTORE/NATIONAL GEOGRAPHIC CREATIVE BOTTOM: NOAH CLAYTON/USGS It’s spring, but frost covers nearly half the boat ferrying Clint Muhlfeld and his crew across Quartz Lake, high in the mountains of Montana’s Glacier National Park They hiked miles to meet the flatbottomed skiff — which was strapped to the bottom of a helicopter and flown in — and carried nets, food, gear and gas because mules couldn’t cross the streams swollen with snowmelt They’re here to tag an invasive species The arduous trip is one of many biologists have made to the park’s lakes in recent years, part of an ongoing search-and-destroy mission to rein in one of the most pernicious aquatic threats in the West: lake trout The sport fish, introduced in lakes over the past 100 years, have outcompeted native bull trout in many of them In Glacier, Muhlfeld is determined to put an end to this slow-moving catastrophe Over the years, lake trout have invaded eight of the park’s 12 connected glacial lakes west of the Continental Divide Quartz Lake was number nine “And that’s where we drew the line,” says Muhlfeld, an aquatic research ecologist with the U.S Geological Survey and the University of Montana “We have to stop this ecological catastrophe, or Glacier’s native fishes will be lost for future generations.” Biologists have tried various ways to rid Western lakes of these invaders, such as electrocuting their eggs or CLOCKWISE FROM BOTTOM LEFT: CHRISTIAN GUY/IMAGEBROKER/ALAMY STOCK PHOTO; VIN D’ANGELO/USGS; CLINT MUHLFELD/USGS; VIN D’ANGELO/USGS; JOEL SARTORE/NATIONAL GEOGRAPHIC CREATIVE Researchers catch adult lake trout (above) in Glacier National Park’s Quartz Lake (right) so they can surgically implant tracking devices (left) These tags lead crews to spawning grounds, where lake trout gather annually in large numbers Then, the teams haul in the invasive species and slaughter them in an effort to aid native bull trout Never mind that it’s backcountrydark out and raining or sleeting or snowing, and headlamps provide the only light as the 25-foot boat bounces over white caps They’re determined to get rid of the lake trout, or at least keep the population low enough that the native bull trout have a chance to thrive TROUT IN TROUBLE The Glacier watershed hosts about one-third of the natural lake habitat for bull trout in the country, but the fish themselves are increasingly scarce Not only must they contend with lake trout, which consume native fish and compete with them for nutrients, now rising temperatures could soon make the water too warm for the cold-loving bull trout to spawn Counts are so low that they’re listed as threatened under the Endangered Species Act The Judas fish has been a blessing for the bull trout of Quartz Lake Over the five years of the project — the intensive phase wrapped up in 2014 — the team hauled more than 2,000 lake trout out of Quartz, finding fewer each year The native bull trout population is exploding, with more nests and some of the highest spawning counts on record “We got there in the nick of time,” Muhlfeld says But the battle isn’t over In many other areas, lake trout are still winning A WATERY HAUL The team has now set its sights on Logging Lake, in another area of the park It poses an even bigger challenge than Quartz: Here, lake trout have already taken over, and there are few bull trout left The Judas fish alone won’t be enough So Muhlfeld and his team are orchestrating a major intervention In collaboration with park management, they’ve moved bull trout from Logging Lake to Grace Lake, which hasn’t been invaded yet It lies above a 40-foot waterfall that lake trout can’t jump LAKE TROUT Salvelinus namaycush Invasive species BULL TROUT Salvelinus confluentis Native species October 2016 DISCOVER 75 Notes From Earth The team had to move the fish by hand, hiking into the backcountry with a low-voltage wand to stun the fish Then they scooped them up and loaded them into a backpack filled with about 35 pounds of oxygenated water and hiked ½ miles uphill to Grace Lake Fully aware that introducing fish to new environments is part of what started this cascade of problems in the first place, graduate student Benjamin Galloway spent two years evaluating the site He found that the only fish species in the Grace Lake system are non-native, hybridized trout with no conservation value, so that isn’t a concern And even if the introduced bull trout move back downstream, they will only land back in Logging Lake Given a fresh start in the safe waters of Grace Lake, the relocated bull trout will likely thrive “They’re iconic They’re at the top of the food chain,” Muhlfeld says “They’ve survived in the park for thousands of years.” A GRAND EXPERIMENT Projects at Yellowstone Lake in Yellowstone National Park and at Idaho’s Priest Lake and Lake Pend Oreille are focused on removing lake 76 DISCOVERMAGAZINE.COM Given a fresh start in the safe waters of Grace Lake, the relocated bull trout will likely thrive trout in the hope that native fish will repopulate But the Glacier team is going one step further “We’re trying to also start a population where one didn’t exist, to hedge our bets over our success or failure in controlling lake trout in downstream waters,” says Chris Downs, the supervisory fisheries biologist and fisheries program manager in Glacier National Park The risks seem minimal, and the alternative is to watch bull trout disappear from the ecosystem, he says And so Muhlfeld’s team hiked, up and down between the lakes, carrying backpacks full of fish In 2014, they relocated 125 bull trout from Logging Lake to Grace Lake Then they took out their new boat, this one customized with a winch to pull in the mile of net, and harvested as many of the remaining lake trout as they could from Logging Lake They took measurements, checked the females for eggs, then “bonked them over the head, cut their air bladder and sunk them to the bottom of the lake,” Muhlfeld says, both to return the nutrients to the system and to keep from attracting grizzlies In the spring, they returned for the juveniles “The idea is that we overharvest the population from both ends, trying to turn off the faucet of reproduction and clean up the fish that sneak through or who have been there prior to suppression,” Muhlfeld says “The hope is that doing both will cause the non-native population to collapse more quickly.” They don’t know yet how many of the bull trout they’ve moved have survived They have an antenna at the Grace Lake outlet, so if any tagged fish leave, they’ll know The hope is that the bull trout will thrive in Grace Lake and the fish will eventually return to Logging Lake “It’s a grand experiment,” Muhlfeld says “But had we done nothing to put them in a safe haven, there wouldn’t be any fish left for us to conserve.” D Janine Latus writes about the art, science and personalities of people who spark her curiosity CHRIS DOWNS/NATIONAL PARK SERVICE (2) Researchers Jon McCubbins (above, foreground), Clint Muhlfeld (middle) and Andrew Lamont capture bull trout to relocate McCubbins (right), a National Park Service biologist, hikes to Grace Lake with native fish in his backpack 650+ Stores Nationwide WOW SUPER COUPON • 1.3 GPM Customer Rating SUPER COUPON 1650 PSI PRESSURE WASHER LOT 69488 SAVE $70 comp at $149.99 om or by calling stores or HarborFreight.c LIMIT - Good at ourused with other discount or coupon or prior 800-423-2567 Cannot be from original purchase with 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one coupon per customer per day • 650+ Stores Nationwide • Lifetime Warranty • Extends from ft to ft 10" • HarborFreight.com • 800-423-2567 om or by calling our stores or HarborFreight.c t or coupon or prior LIMIT - Good at used with other discoun 800-423-2567 Cannot be from original purchase with original receipt purchases after 30 days last Non-transferable Original coupon must be Offer good while supplies1/6/17 Limit one coupon per customer per day presented Valid through At Harbor Freight Tools, the "comp at" price means that the same item or a similar functioning item was advertised for sale at or above the "comp at" price by another retailer in the U.S within the past 180 days Prices advertised by others may vary by location No other meaning of "comp at" should be implied For more information, go to HarborFreight.com or see store associate History Lessons A Profile of Plague We still have much to learn — and fear — from the ancient pestilence BY HILLARY WATERMAN → 78 DISCOVERMAGAZINE.COM Over the centuries, Yersinia pestis (right), also known as plague, decimated Europe’s population many times over In a modern outbreak of plague, antibiotics and other treatments help us fare better But it’s only been in the past decade that genome analysis has given the bacteria an evolutionary history, allowing us to link modern studies to past experiences disease Yet Arizona State University historian and author Monica Green says it’s only been in the past decade that genome analysis has given the bacteria an evolutionary history of plague, allowing us to link modern studies to past experiences Before these discoveries, she says, “I wouldn’t even teach a class on [it], because we didn’t know what it was.” PLAGUE’S PARTICULARS Beginning in the mid-14th century with the Black Death and continuing TOP: PICTORIAL PRESS LTD/ALAMY STOCK PHOTO BOTTOM: EYE OF SCIENCE/SCIENCE SOURCE In 2007, a wildlife biologist working for the National Park Service at the Grand Canyon discovered one of the collared mountain lions he had been tracking The animal was dead Concerned, he removed the lion’s body, took it home and performed a post-mortem examination Within a week, he was dead, too The cause of death for both: Yersinia pestis, commonly known as plague The deaths, along with dozens of cases since, are a vivid reminder that the disease is alive and well Y pestis is a bacterium that lives in the bellies of fleas, which live on rodents, some of which, like rats, live near humans Scholars estimate that plague killed up to half the European population during the Middle Ages, and for most the death was a painful, slow end Although it has been an Old World menace for millennia, the disease hitchhiked to our shores on trade ships from Asia only in 1900 It caused a few rounds of epidemic before receding in 1925 to rural rodent populations, where it occasionally causes small-scale outbreaks Last year, the Centers for Disease Control and Prevention reported 16 plague infections in the U.S., mostly in western states Four of them were fatal In a modern outbreak of plague, antibiotics and other medical advances help us fare better, but it remains a particularly nasty CLOCKWISE FROM LEFT: SPL/SCIENCE SOURCE (2); ROBERT HOOKE/MICROGRAPHIA/NATIONAL LIBRARY OF MEDICINE; SPL/SCIENCE SOURCE with successive waves, the deadly pestilence sucker-punched Europe’s population for 300 years, killing hundreds of millions of people in all — between one-third and one-half of the populace No one knew what caused it People had no knowledge of bacteria, so the panicky populace instead clung to specious theories about plague’s cause: bad smells, dank air, an imbalance of body humors, even God’s wrath Contemporaries called it “The Great Mortality.” Bubonic plague in particular was recognizable by the horrifying appearance of buboes, blackened swellings in the victim’s groin and armpits In its pneumonic form, the variation that killed the Grand Canyon mountain lion and ill-fated biologist, the infection goes straight to the victim’s lungs, dealing death within a day of the first appearance of fever and bloody sputum A victim could be healthy at breakfast, dead before sundown Maritime trade routes had spread plague around the world by the 19th century At that point, new microscopy technology and the germ theory of disease had revolutionized medicine Researchers could now see the culprits and distinguish between similar diseases such as anthrax, cholera and, yes, bubonic plague, which was isolated in 1894 the scholarly community, contended and named Yersinia pestis in honor that the Black Death had been a of Swiss microbiologist Alexandre dramatically more virulent infection Yersin These diseases still posed a than the modern-day bubonic plague major threat, but now doctors could These individuals argued that a different study them and develop science-based organism, perhaps anthrax or typhus, responses: Many cities in the U.S originally caused the Black Death and Europe established public health “With nothing but written documents,” boards, improved sanitation and Green says, “they were speculating instituted quarantines at the first sign about something they would never of disease spread find evidence of It could have been Finally, with the widespread use of anything We just didn’t know.” penicillin in the 1940s, doctors Extent of area reached had an effective by Black Death way to treat the 1347 Area unaffected 1348 No reliable data disease, and 1349 interest in the 1350 1351 plague became 1352 more academic By the 1970s, “plague deniers,” a vocal faction within Alexandre Yersin (left) isolated the plague bacteria, which now bears his name, in a Shanghai hut (top left) The bacteria often travel in the bellies of fleas (above) Finally, in 1998, a landmark study demonstrated that microorganisms could be — and usually are — preserved in the pulp of teeth after people die This opened up new avenues of exploration in the burgeoning fields of paleogenetics and aDNA (ancient DNA) analysis By 2011, geneticists, working with samples harvested by bioarchaeologists from a known plague cemetery in London, had fully sequenced the genome of 14th century Y pestis When they compared the ancient plague genome with that of modern plague and October 2016 DISCOVER 79 History Lessons of plague, but it was humans who likely gave it the highways to travel At that time, the extensive trade network known as the Silk Road ran throughout Eurasia The trade routes were dotted with caravanserai, THE ROLE OF CLIMATE mass encampments where Since then, we’ve learned travelers could eat, lodge, even more about plague’s buy supplies and refresh past — and its possible their camels, a favorite future In a 2015 paper in host of the fleas that the journal PNAS, Boris carry Y pestis Schmid of the University “Camels appear to get of Oslo proposed a less sick from plague than climate-based explanation humans, and thus might for the cyclical epidemics last longer before they that characterized the succumb,” Schmid says disease’s presence in An infected camel could Europe carry fleas far along Schmid’s team analyzed the route before dying tree rings and growth The caravanserai were patterns from a variety of likely critical in plague juniper in the Karakorum dispersal Mountains of Y pestis’ While the disease Plague doctors wore masks to avoid the bad air they blamed for the disease native western Central Asia remains a modest threat Because the trees can live to in rural, undeveloped be 1,000 years old, Schmid could study areas, Green warns that our current samples from individual trees alive stable relationship with plague in during the Black Death the developed world is only as good Statistical analysis revealed as our control of urban rodent a pattern: Each documented populations Even then, outside of introduction of plague in Europe our cities, the occasional unfortunate was preceded by a significant climate brush with Y pestis will occur, as event in Asia, such as a sudden shift the fate of the Park Service biologist in the annual monsoon pattern in the reminds us mid-14th century, which pushed the Human populations are more northern border of activity from China mobile than ever, and our travel to Siberia In every case, the Asian patterns combined with unchecked climate event preceded a major plague climate change only exacerbate the outbreak in Europe by almost exactly risk of outbreaks If global warming 15 years The pattern held for plague disrupts the status quo, we may again reintroductions via both land routes It was a cycle that often repeated see Y pestis take deadly advantage of and maritime trade networks itself Schmid’s team pinpointed highly trafficked areas to wreak havoc The team reasons that large-scale three major pulses of plague on our population “We will never climate fluctuations in Asia caused introductions in Europe, coinciding be able to fully let our guard down,” rodent colonies to collapse Desperate with the continent’s three centuries Green says D fleas sought new hosts, jumping of Black Death Hillary Waterman is an anthropologist aboard passing animals, and plague Climate shifts created the right and science writer based in Maine got a free ride across the continent conditions for the westward advance Climate shifts created the right conditions for the westward advance of plague, but it was humans who likely gave it the highways to travel 80 DISCOVERMAGAZINE.COM DEA PICTURE LIBRARY/DE AGOSTINI/GETTY IMAGES placed it on the family tree, “Boom!” says Green “It was directly related to the strain we see in the world today; we not have reason to believe it was significantly more virulent This was a game changer.” CLASSIFIEDS T R AV E L AMAZON RAINFOREST Award-winning lodge in Tamshiyacu-Tahuayo Reserve, shown to have the world’s greatest diversity of primates Customized itineraries, daily departures 1-800-262-9669 Visit: www.perujungle.com COMPELLING SCIENCE for curious minds Newton’s apple Edison’s lightbulb Hawking’s astrophysics DO YOU HAVE A PRODUCT, OR SERVICE YOU WANT TO PROMOTE TO OVER MILLION READERS? ADVERTISE HERE Subscribe to Discover magazine and see where your curiosity takes you THE YEAR IN SCIENCE Discover SCIENCE FOR THE CURIOUS January/February 2016 100 TOP STORIES OF 2015 CONTACT STEVE MENI FOR INFORMATION, RATES, AND THE NEXT AVAILABLE ISSUE 888-558-1544 ext 628 SMENI@DISCOVERMAGAZINE.COM Antibiotic Breakthrough Biggest SETI Search Ever Human Gene Editing Limb Grown in a Lab The End of the Universe? and More PLUTO SHINES A big year for the little world 10 issu es JUST $19 95 Go to DiscoverMagazine.com or call 1-800-829-9132 Available in print or digital format ZOBRIST CUBE TM 20,000 Puzzles in a Box! 33 POLYCUBE PIECES & 52 PAGE CODE BOOK www.ZobristCube.com (855) 962-7478 Ages - Adult 20 Things You Didn’t Know About … Making up one-fifth of all living mammal species and found on six continents, bats range from the insect-loving greater mouse-eared bat (top right), to fruit bats (top) and the poetically named Botta’s Serotine (above) 82 BY GEMMA TARLACH It’s time for bats to come out of the shadows and get their due as an evolutionary success story: About one-fifth of all living mammal species are of the order Chiroptera (“hand-wing”), found on every continent but Antarctica It’s likely bats once flew over Antarctic skies, too A 2005 study in Molecular Biology and Evolution found ancestral New World bats probably spread from the Americas to Australia about 42 million years ago via the now-frozen continent, which was then temperate Some of those far-flying early bats settled in New Zealand and evolved into three different species, which are the island nation’s only native land mammals New Zealand bats are often called pekapeka, the name the indigenous Maori people gave them It might sound adorable, but Maori folklore associates the animals with death and calamity In fact, while bats are symbols of good luck in China, most other cultures side with the Maori It’s probably because the animals are active at night, the opposite of naturally diurnal humans who have long associated darkness with danger Bats pose some danger as vectors of disease, including rabies Researchers suspect they may also carry Marburg, a relative of Ebola, and coronaviruses such as SARS Our perception of the threat may be exaggerated, though In June, a review in Trends in Parasitology found that bats carry far fewer infectious diseases than rodents And they’re definitely not rodents In the late 20th century, based on initial genetic research, bats were grouped with primates and flying lemurs in the superorder Archonta More recent genetic analysis — not yet universally accepted — places bats in the superorder Laurasiatheria, with a diverse bunch of other placental mammals including whales, dogs and giraffes 10 Chiroptera’s fossil record is spotty because the earliest bats, like today’s species, had small, delicate skeletons that had to be buried in sediment immediately after death to be preserved 11 We know this: About 52.5 million years ago in what’s now Wyoming, early bat Onchonycteris finneyi was already capable of powered flight 12 Bats are the only mammals with this trait; they also take to the skies differently than other flying animals Unlike the more rigid wings of birds and insects, bat wings have multiple joints and move in and out as well as up, down, back and forth with every stroke 13 One thing bats have in common with birds: According to research released in June, the outer layer of their skin contains a compound that enhances pliability — handy when flight depends on your flexible wings No other mammal has this adaptation 14 You might think echolocation is another defining Chiroptera trait, but not all bats send out sound waves that bounce off prey and potential obstacles to create a picture of their environment 15 Fruit bats, for example, generally rely on their eyesight to find food For decades, it was assumed they didn’t echolocate, and most don’t But a 2014 study found three fruit bat species sometimes use a rudimentary method of echolocation: They make a clicking noise with their wings to navigate in darkness 16 If not for the Vikings, we might call a bat a “rearmouse.” It derives from the Anglo-Saxon term for the animal, hreáðe-mús As Norsemen moved into what’s now the United Kingdom, beginning in the ninth century, bakke, of Scandinavian origin, gradually replaced the word and evolved into bat 17 “Rearmouse” persists colloquially today in areas of Great Britain that never fell under Scandinavian influence, including pockets of Wales and England’s southwest 18 Bats jam Seriously A 2014 Science study found that when competing for food, Mexican free-tailed bats emit an ultrasonic signal that effectively blocks the sound waves another bat sends out to home in on an insect The interference causes the rival to miss its target 19 Something else that’s off-target: the myth that bats get tangled in long hair Some scholars trace the notion to an early Christian edict that women must cover their heads because their hair attracted demons Already associated with devilish things, bats were assumed also to have a thing for hair 20 One more fiction that makes us batty is the whole vampire thing Only three of the more than 1,200 bat species are sanguivorous Any bat you meet is far more likely to eat a mosquito or pollinate fruit than go for your jugular D In memory of Catherine Chenoweth, a friend of bats and of Senior Editor Gemma Tarlach DISCOVER (ISSN 0274-7529, USPS# 555-190) is published monthly, except for combined issues in January/February and July/August Vol 37, no Published by Kalmbach Publishing Co., 21027 Crossroads Circle, P.O Box 1612, Waukesha, WI 53187-1612 Periodical postage paid at Waukesha, WI, and at additional mailing offices POSTMASTER: Send address changes to DISCOVER, P.O Box 62320, Tampa, FL 33662-2320 Canada Publication Agreement # 40010760 Back issues available All rights reserved Nothing herein contained may be reproduced without written permission of Kalmbach Publishing Co., 21027 Crossroads Circle, P.O Box 1612, Waukesha, WI 53187-1612 Printed in the U.S.A DISCOVERMAGAZINE.COM FROM TOP: INGO ARNDT/NATUREPL.COM; HANS CHRISTOPH KAPPEL/NATUREPL.COM; BROCK FENTON Bats GEAR, PHOTOS, FLIGHT, PERSPECTIVE, AND THE FUTURE! 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