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Like most moms and dads, my time in the post-baby throes of sleep deprivation is a hazy memory. But I do remember feeling instant rage upon hearing a popular piece of advice for how to get my little one some shut-eye: “sleep begets sleep.” The rule’s reasoning is unassailable: To get some sleep, my baby just had to get some sleep. Oh. So helpful. Thank you, lady in the post office and entire Internet.

So I admit to feeling some satisfaction when I came across a study that found an exception to the “sleep begets sleep” rule. The study quite reasonably suggests there is a finite amount of sleep to be had, at least for the 50 Japanese 19-month-olds tracked by researchers.

The researchers used activity monitors to record a week’s worth of babies’ daytime naps, nighttime sleep and activity patterns. The results, published June 9, 2016, in Scientific Reports, showed a trade-off between naps and night sleep. Naps came at the expense of night sleep: The longer the nap, the shorter the night sleep, the researchers found. And naps that stretched late into the afternoon seemed to push back bedtime.

In this study, naps didn’t affect the total amount of sleep each child got. Instead, the distribution of sleep across day and night changed. That means you probably can’t tinker with your toddler’s nap schedule without also tinkering with her nighttime sleep. In a way, that’s reassuring: It makes it harder to screw up the nap in a way that leads to a sleep-deprived child. If daytime sleep is lacking, your child will probably make up for it at night.

A sleeping child looks blissfully relaxed, but beneath that quiet exterior, the body is doing some incredible work. New concepts and vocabulary get stitched into the brain. The immune system hones its ability to bust germs. And limbs literally stretch. Babies grew longer in the four days right after they slept more than normal, scientists reported in Sleep in 2011. Scientists don’t yet know if this important work happens selectively during naps or night sleep.

Right now, both my 4-year-old and 2-year-old take post-lunch naps (and on the absolute best of days, those naps occur in glorious tandem). Their siestas probably push their bedtimes back a bit. But that’s OK with all of us. Long spring and summer days make it hard for my girls to go to sleep at 7:30 p.m. anyway. The times I’ve optimistically tried an early bedtime, my younger daughter insists I look out the window to see the obvious: “The sky is awake, Mommy.”

A question flamingo researchers get asked all the time — why the birds stand on one leg — may need rethinking. The bigger puzzle may be why flamingos bother standing on two.

Balance aids built into the birds’ basic anatomy allow for a one-legged stance that demands little muscular effort, tests find. This stance is so exquisitely stable that a bird sways less to keep itself upright when it appears to be dozing than when it’s alert with eyes open, two Atlanta neuromechanists report May 24 in Biology Letters.
“Most of us aren’t aware that we’re moving around all the time,” says Lena Ting of Emory University, who measures what’s called postural sway in standing people as well as in animals. Just keeping the human body vertical demands constant sensing and muscular correction for wavering. Even standing robots “are expending quite a bit of energy,” she says. That could have been the case for flamingos, she points out, since effort isn’t always visible.
Ting and Young-Hui Chang of the Georgia Institute of Technology tested balance in fluffy young Chilean flamingos coaxed onto a platform attached to an instrument that measures how much they sway. Keepers at Zoo Atlanta hand-rearing the test subjects let researchers visit after feeding time in hopes of catching youngsters inclined toward a nap — on one leg on a machine. “Patience,” Ting says, was the key to any success in this experiment.

As a flamingo standing on one foot shifted to preen a feather or joust with a neighbor, the instrument tracked wobbles in the foot’s center of pressure, the spot where the bird’s weight focused. When a bird tucked its head onto its pillowy back and shut its eyes, the center of pressure made smaller adjustments (within a radius of 3.2 millimeters on average, compared with 5.1 millimeters when active).
Museum bones revealed features of the skeleton that might enhance stability, but bones alone didn’t tell the researchers enough. Deceased Caribbean flamingos a zoo donated to science gave a better view. “The ‘ah-ha!’ moment was when I said, ‘Wait, let’s look at it in a vertical position,’” Ting remembers. All of a sudden, the bird specimen settled naturally into one-legged lollipop alignment.

In flamingo anatomy, the hip and the knee lie well up inside the body. What bends in the middle of the long flamingo leg is not a knee but an ankle (which explains why to human eyes a walking flamingo’s leg joint bends the wrong way). The bones themselves don’t seem to have a strict on-off locking mechanism, though Ting has observed bony crests, double sockets and other features that could facilitate stable standing.

The bird’s distribution of weight, however, looked important for one-footed balance. The flamingo’s center of gravity was close to the inner knee where bones started to form the long column to the ground, giving the precarious-looking position remarkable stability. The specimen’s body wasn’t as stable on two legs, the researchers found.
Reinhold Necker of Ruhr University in Bochum, Germany, is cautious about calling one-legged stances an energy saver. “The authors do not consider the retracted leg,” says Necker, who has studied flamingos. Keeping that leg retracted could take some energy, even if easy balancing saves some, he proposes.

The new study takes an important step toward understanding how flamingos stand on one leg, but doesn’t explain why, comments Matthew Anderson, a comparative psychologist at St. Joseph’s University in Philadelphia. He’s found that more flamingos rest one-legged when temperatures drop, so he proposes that keeping warm might have something to do with it. The persistent flamingo question still stands.

Astronomers want you in on the search for the solar system’s ninth planet.

In the online citizen science project Backyard Worlds: Planet 9, space lovers can flip through space images and search for this potential planet as well as other far-off worlds awaiting discovery.

The images, taken by NASA’s Wide-field Infrared Survey Explorer satellite, offer a peek at a vast region of uncharted territory at the far fringes of the solar system and beyond. One area of interest is a ring of icy rocks past Neptune, known as the Kuiper belt. Possible alignments among the orbits of six objects out there hint that a ninth planet exerting its gravitational influence lurks in the darkness (SN: 7/23/16, p. 9). The WISE satellite may have imaged this distant world, and astronomers just haven’t identified it yet. Dwarf planets, free-floating worlds with no solar system to call home (SN: 4/4/15, p. 22) and failed stars may also be hidden in the images.
The WISE satellite has snapped the entire sky several times, resulting in millions of images. With so many snapshots to sift through, researchers need extra eyes. At the Backyard Worlds website, success in spotting a new world requires sharp sight. You have to stare at what seems like thousands of fuzzy dots in a series of four false-color infrared images taken months to years apart and identify faint blobs that appear to move. Spot that movement and you may have found a new world.

But you can’t let blurry spots or objects moving in only a couple of the frames fool you: Image artifacts can look like convincing space objects. True detections come from slight shifts in the positions of red or whitish-blue dots. With so many dots to track, it’s best to break up an image into sections and then click through the four images section by section. This process can take hours. But think of the payoff — discovering a distant world no one has observed before.

Once you’ve marked any potential object of interest, the project’s astronomers take over. Jackie Faherty of the American Museum of Natural History in New York City and colleagues cross-reference the object’s coordinates with databases of celestial worlds. If the object does, in fact, appear to be a newbie, the team requests time on other telescopes to do follow-up. Those studies can reveal whether the object is a failed star or a planet.

So far, tens of thousands of citizen scientists have scoured images at Backyard Worlds. The team has identified five possible failed stars and had its first paper accepted for publication.

But there’s still much more to explore: The elusive Planet Nine might still be out there, disguised as a flash of dots.

After an influenza infection, the nose recruits immune cells with long memories to keep watch for the virus, research with mice suggests.

For the first time, this type of immune cell — known as tissue resident memory T cells — has been found in the nose, researchers report June 2 in Science Immunology. Such nasal resident memory T cells may prevent flu from recurring. Future nasal spray vaccines that boost the number of these T cells in the nose might be an improvement over current flu shots, researchers say.
It’s known that some T cell sentinels take up residence in specific tissues, including the brain, liver, intestines, skin and lungs. In most of these tissues, the resident memory T cells start patrolling after a localized infection. “They’re basically sitting there waiting in case you get infected with that pathogen again,” says Linda Wakim, an immunologist at the University of Melbourne in Australia. If a previous virus invades again, the T cells can quickly kill infected cells and make chemical signals, called cytokines, to call in other immune cells for reinforcement. These T cells can persist for years in most tissues.

It’s different in the lungs. There, resident memory T cells have shorter-term memories than ones that reside in other tissues, scientists have previously found. To see if all tissues in the respiratory tract have similarly forgetful immune cells, Wakim and colleagues tagged immune cells in mice and sprayed flu virus in the rodents’ noses. After infection, resident memory T cells settled into the nasal tissue. The researchers haven’t yet dissected any human noses, but it’s a pretty good bet they also contain resident memory T cells, Wakim says.
Unlike in the lungs, the nose T cells had long memories, persisting for a least a year. “For mice, that’s quite a long time, almost a third of their life,” Wakim says. She doesn’t yet know why there’s a difference between nose and lung T cell memories, but finding out may enable researchers to boost lung T cell memory.
Still, with nose T cells providing security, the lungs might not need much flu-fighting memory. Memory T cells that patrol only the upper respiratory tract could stop viruses from ever reaching the lungs, Wakim’s team found. An injection of virus under the skin didn’t produce any resident memory T cells in the respiratory tract. Those findings could mean that vaccines delivered via nasal spray instead of shots might stimulate memory T cell growth in the nose and could protect lungs from damage as well. A nasal spray called FluMist has had variable results in people. No one knows if that vaccine can produce nasal memory T cells.
It’s not surprising to find that the nose has its own resident memory T cell security force, says Troy Randall, a pulmonary immunologist at the University of Alabama at Birmingham. “But it’s a good thing to know and certainly they’re the first to show it.”

The discovery may direct some research away from the lungs and toward the nose, Randall says. Future research should focus on how the resident memory T cells work with memory B cells that produce antibodies against viruses and bacteria, he suggests.

Water swirling down a drain has exposed an elusive phenomenon long believed to appear in black holes.

Light waves scattering off a rotating black hole can bounce off with more energy than they came in with, by sapping some of the black hole’s rotational energy. But the effect, predicted in 1971 and known as rotational superradiance, is so weak that it would be extremely difficult to observe in a real black hole. So scientists had never seen rotational superradiance in action. Now, physicists report June 12 in Nature Physics that they’ve glimpsed the effect for the first time, in a black hole doppelgänger made with a vortex of water, similar to water swirling down a bathtub drain.
“If you take a tennis ball and you throw it against a wall, you don’t expect it to come back with more energy,” says Silke Weinfurtner of the University of Nottingham in England, who led the study. “But when you throw something at a black hole, if it’s a rotating black hole, you can actually gain energy.”

To demonstrate the effect, the scientists created a swirl of water. “The fluid has to drain in a way that looks like a black hole,” says physicist Antonin Coutant, also at Nottingham. Surface ripples reach a point of no return where they are sucked into the vortex. That’s analogous to a black hole’s event horizon, the boundary from which no light can escape. Weinfurtner, Coutant and colleagues report that water waves scattering off the vortex got a superradiant boost: They were amplified by up to 14 percent on average, depending on the frequency and direction of the waves.

For obvious reasons, researchers can’t study a real black hole in a laboratory. If they could, “we’d all be in trouble,” says physicist Sam Dolan of the University of Sheffield in England, who was not involved with the study. A water vortex is the next best thing. The result, Dolan says, “gives us more confidence that our theories about black holes are correct.”

Although rotational superradiance is a weak effect in black holes, there may be opportunities to observe it, says physicist Vítor Cardoso of Instituto Superior Técnico in Lisbon, Portugal. Superradiance affects gravitational waves as well as light waves. Ripples in spacetime stirred up by merging black holes (SN Online: 6/1/17) should be slightly amplified if those black holes are spinning. That amplification could be observed by future ultrasensitive gravitational wave detectors.

For the first time, researchers have watched relatively cool parcels of plasma speed away from the surface of the sun and off into space, all the while cocooned in a million-degree flare.

Shadia Habbal of the University of Hawaii in Honolulu and colleagues used a specially designed spectrometer to observe the eruption from Svalbard, Norway, during the March 2015 solar eclipse. The results, published online June 9 in Astrophysical Journal Letters, include measurements of the speed, temperature and composition of filaments of solar material streaming away from the sun — three features never measured simultaneously before.
The data provide the first direct evidence of cooler solar material within an eruption and map its speed and trajectory, says Enrico Landi of the University of Michigan in Ann Arbor. “No instrument has ever been able to obtain these data.”

The sun’s surface is a roiling mass of hot ionized gas, or plasma, which is about a roasty 6,000° Celsius. But its corona, the wispy, halolike atmosphere that is visible during a solar eclipse, is superheated to millions of degrees. Scientists are still not sure how it gets so hot.Every so often, a huge, hot bubble of coronal plasma appears to burst off the sun’s surface in an eruption called a coronal mass ejection, or CME. These ejections send energetic charged particles hurtling into space at millions of miles per hour. When aimed at Earth, those particles can damage satellites and knock out power systems (SN Online: 4/9/12), so scientists want to understand CMEs to better predict them.
The trouble is, it’s difficult to watch CMEs close to their origins. Sun-watching spacecraft block out the bulk of the sun’s light with a shield to avoid blinding their cameras. That gives spacecraft a constant view of the shimmering corona, but hides the sun’s surface.

The March 20, 2015, total solar eclipse over Svalbard gave Habbal’s team a rare view of the whole solar atmosphere because the moon and the sun appear almost the same size in the sky. “You can see things right from the solar surface out to several solar radii,” she says.

Her team brought a custom-built spectrometer the size of an airline-approved carry-on, designed by coauthor Adalbert Ding of the Technical University of Berlin. The spectrometer is sensitive to wavelengths of light emitted by iron atoms that have lost all but 11 or 14 of their electrons. Researchers can use those iron ions in the solar material to trace temperature: The hotter the solar plasma, the more electrons the iron has lost.
As expected, coronal temperatures soared to 2 million or so degrees Celsius. But the team also saw some cooler blobs at a mere 20,000° C. Instead of losing their electrons to the heat and becoming ionized, these blobs maintained their cool.

Habbal thinks these are bright fingers of plasma called prominences, which had previously been observed stretching away from the sun before a CME.

“If you have an ice cube in a hot bath, it’s going to melt and evaporate,” Habbal says. “Here you have clusters of cool material that are enwrapped by very hot material. You would expect them to get ionized, but they didn’t.”

By measuring the solar material’s Doppler shift, or the change in wavelength as the material moved, the instrument could also clock its speed and direction. If the wavelength of the light appeared longer (or redder) in some places, that means the material was moving away from the observers. Shorter wavelength, or bluer light, indicated material moving toward them.

During the eclipse, material around the solar disk zoomed away at 100 to 1,500 kilometers per second. Such great speeds indicated that a CME erupted, and the direction suggested it was on the far side of the sun. Catching a CME during the short eclipse was a lucky coincidence.

“Lots of things about this experiment were just sheer luck,” Habbal says.

Cool inclusions have been spotted inside the hot corona before, but this is the first time they were seen fleeing the surface of the sun during a CME, Habbal says.

Prominences are thought to be associated with CMEs, and might even trigger their eruptions, but no one is sure how. Now that it’s possible to trace them from the solar surface out into space, researchers hope to spot more during the total eclipse as it crosses the United States in August (SN: 8/20/16, p. 14).

“If successful, it will be the dataset of a lifetime,” says Landi.

Hunter-gatherers who built and worshiped at one of the oldest known ritual centers in the world carved up human skulls in a style all their own.

At Turkey’s Göbekli Tepe site — where human activity dates to between around 11,600 and 10,000 years ago — people cut deep grooves in three human skulls and drilled a hole in at least one of them, say archaeologist Julia Gresky of the German Archaeological Institute in Berlin and colleagues. Ancient hunter-gatherers there practiced a previously unknown version of a “skull cult,” in which human skulls were ritually modified after death and then deposited together, Gresky’s team reports online June 28 in Science Advances.

Collections of human skulls modified in other ways have been found at several sites from around the same time. For instance, deliberately broken faces on skulls were unearthed at a Syrian settlement and may represent a form of punishment after death.

Seven excavated skull fragments enabled Gresky’s group to reconstruct the Göbekli Tepe skulls. These skulls of the recently deceased were carved for use in ceremonies to worship them as ancestors, the researchers propose. It’s also possible that the skull incisions marked deceased individuals who had been especially revered or reviled while alive.

A cord inserted through the hole drilled in one skull may have suspended that skull for display. Grooves probably ran from front to back on the skulls and possibly stabilized cords that held decorations of some kind.

Microscopic study of skull pieces from Göbekli Tepe indicates that grooves were cut with stone tools. A lack of healed bone on the edges of incisions suggests skull carving occurred shortly after death.

PORTLAND, Ore. — Petals of wildflowers called starry campions may be a pretty little battleground for a sexual skirmish between the plant’s male and female parts.

As is common in flowers, each Silene stellata bloom forms both male and female sex organs. After measuring petal variation between plants and tracking parenthood of seeds, Juannan Zhou suspected a sexual tug-of-war.

Flowers with greater male success in spreading pollen and siring seeds across a flower patch tended toward longer and narrower petals, Zhou reported June 26 at the Evolution 2017 meeting. Yet flowers that did especially well by their female organs, maturing abundant seeds in their own ovaries, tended toward wider and shorter petals.
Zhou, of the University of Maryland in College Park, pieced together the story while working in a fenced-in plot of wild campions at Mountain Lake Biological Station in southwestern Virginia. During two summers, he tracked floral details and collected seeds. He sprouted almost 2,400 seedlings and for each genetically worked out which of 227 fenced-in adults had been the father.

If a conflict smolders between what’s best for male versus female functions, parental blossom trends that went along with greater fatherhood should tilt in the opposite direction from blossom trends linked with greater motherhood. Some traits such as number of fringe tassels showed no signs of conflict, but petal dimensions did.

Zhou suggests that the contrary trends might arise from the sexes’ opposite interests in visits from one of its pollinating moths, the mottled gray-brown Hadena ectypa. These moths do much of the pollen carrying early in midsummer. One mothload of pollen typically fertilizes all the eggs a female has, so from the motherhood perspective, once is enough. More than once means more risk for little benefit, because female moths leave an unwanted gift behind.

Besides sucking nectar, a H. ectypa often sticks her rear into the cup of a flower and with a wiggle, lays an egg or two. When eggs hatch, the tiny caterpillars chew their way into the flower ovary and start feeding on the plant’s own seeds. Caterpillars eventually grow too long and fat to fit inside blooms. Certain petal shapes, Zhou speculates, might be more attractive to moths, or perhaps more discouraging for the fattest, most destructive caterpillars to invade.

From the male point of view, the loss of the home flower’s seeds could be more than recouped by repeated moth visits to pick up more pollen to spread to other flowers. More moths could mean many more offspring.
Sexual conflicts show up elsewhere in nature, such as in the compounds that fruit flies use to dope their sperm. After a jolt of these extras, females tend to put more resources into eggs and offspring. Never mind that it shortens a female’s life. Data on sexual conflicts from plants are much rarer, says evolutionary ecologist Locke Rowe of the University of Toronto. He welcomes the starry campion work also because the plants are hermaphrodites, a lifestyle uncommon in conflict studies.

People and pooches may have struck up a lasting friendship after just one try, a new genetic study suggests.

New data from ancient dogs indicates that dogs became distinct from wolves between 20,000 and 40,000 years ago, researchers report July 18 in Nature Communications. Dogs then formed genetically distinct eastern and western groups 17,000 to 24,000 years ago, the researchers calculate. That timing and other genetic data point to dogs being domesticated just once.

That idea contrasts with a hypothesis put forward last year that dogs were domesticated separately in Europe and East Asia, with the Asian dogs eventually replacing the European mutts (SN: 7/9/16, p. 15).
Scientists agree that dogs stem from wolves, but where, when and how many times dogs were domesticated — passing down tameness and other traits over generations — has been rethought many times in the last few years (SN: 7/8/17, p. 20).

The new study “puts dog origins into one time and place again. That’s really important,” says Peter Savolainen, an evolutionary geneticist at KTH Royal Institute of Technology in Stockholm who was not involved in either study. These new data indicate “there’s a single origin, and it wasn’t in Europe,” says Savolainen, a proponent of an East Asian origin of dogs.

The new study examined the complete genetic blueprints, or genome, from a 7,000-year-old dog from Herxheim in Germany, and a 4,700-year-old dog from Cherry Tree Cave (also known as Kirshbaumhöle) in Germany. The scientists also analyzed DNA data from a 4,800-year-old dog from Newgrange, Ireland, that had been described in the previous study positing two domestication events.
A claim of multiple domestications for dogs requires extraordinary evidence, says study coauthor Krishna Veeramah, an evolutionary geneticist at Stony Brook University in New York. But complete genomes of the ancient dogs suggest a simpler story. “We can explain all of our data just using one domestication event,” Veeramah says.
Although Veeramah and colleagues see a split between eastern and western dogs, that split probably happened after domestication took place. Modern European dogs still share heritage with Stone Age canines on the continent, hinting that all the pups came from a common source rather than separately domesticated Asian dogs replacing their European counterparts.

These new data don’t completely rule out multiple domestications (the single event is just the simpler explanation), nor do they indicate where humans and canines became BFFs, Veeramah says. A family tree constructed from the DNA data puts today’s Southeast Asian breeds on the earliest branch, implying an origin in Asia. But a dog breed’s present-day location may not reflect where dogs were actually domesticated more than 20,000 years ago, Veeramah says.

The team that proposed double domestication is not convinced of a single origin. The new study is based on genetic data alone and doesn’t take archaeological evidence into account, says Greger Larson, an evolutionary geneticist at the University of Oxford.

“There’s no smoking gun here, and there’s no direct contradiction,” says Larson. “Our hypothesis of a dual origin remains a possibility, as does a single origin.” Researchers won’t know for sure until they’ve analyzed older dogs from multiple places.

The ancient doggy data also challenge a recently proposed idea that dogs were domesticated when early mongrels developed the ability to digest starch better than wolves could (SN Online: 1/23/13), allowing them to eat grains in early farmers’ trash heaps. A previous study found that today’s dogs have many copies of the AMY2B gene, which produces an enzyme that helps break down starch, while wolves have only two copies.

The new study finds that both ancient German dogs had two copies of AMY2B, while the Newgrange dog had three. Since those dogs lived thousands of years after domestication, the findings suggest the first domesticated dogs were no better equipped to digest starch than wolves were. But the ancient dogs do have other genetic variants that made it possible for the amylase gene to be copied later, Veeramah says. Exactly when that happened isn’t clear.

In July of 1972, NASA launched the first Landsat satellite into orbit around Earth. Since then, the spacecraft and its successors have transformed our understanding of Antarctica (and the rest of the planet, too). In the first year following the launch, Landsat’s images of the faraway continent showed “uncharted mountain ranges, vast ice movements and errors in maps as little as two years old,” according to an article published in Science News. William MacDonald of the U.S. Geological Survey, who had spent eight years mapping a part of West Antarctica, was “shocked” to learn of previously unknown peaks just 100 miles from McMurdo Station.

Landsat’s images weren’t the first overhead shots of Antarctica, but to this day the program provides researchers a reliable and repeating view of hard-to-reach corners of the planet. It was Landsat images that in November of 2014 first alerted scientists to a growing crack in the Larsen C ice shelf that, after lengthening by about 20 kilometers in less than nine months, threatened to break off a Delaware-sized chunk of the shelf. With thermal imagery from Landsat 8 along with data from the European Space Agency’s Sentinel-1 satellites, scientists sitting half a world away tracked the Larsen C crack to its final break, as described by Ashley Yeager.
While satellites are scientists’ eyes in the skies, seismic sensors serve as ears to the ground. Alexandra Witze describes the work of scientists who are using seismic sensors to monitor nuclear weapons activity in a part of the planet where access to information is limited: North Korea. Five nuclear weapons tests have been confirmed in the country since 2006, all at an underground test site in Mount Mantap. By tracking seismic waves produced by such explosions, and comparing these rumbles with each other and with those produced by natural earthquakes and in experimental tests, researchers around the world gain valuable clues to where the hidden explosions are happening and, importantly, how powerful they are. A North Korea weapons test last year was detected as far away as Bolivia.

The art of eavesdropping certainly has its rewards. There are plenty more examples. Rachel Ehrenberg writes about how snooping scientists might listen in on kelp to predict ecosystem health. And Emily Conover reports on a newly discovered, relatively itty-bitty star some 600 light-years away. Astronomers spied on the star by watching it pass in front of a larger star, dimming the larger star’s light.

Sometimes astronomers get lucky and distant phenomena are much more straightforward to study. That will be the case later this month when a total solar eclipse passes across North America from Oregon to South Carolina. People will be monitoring the August 21 eclipse in all sorts of ways, including via a livestream from balloons at the edge of the atmosphere, as Lisa Grossman describes in “Watch the moon’s shadow race across the Earth from balloons.” Grossman will be reporting on the eclipse on the ground with scientists in Wyoming. You’ll find her stories — along with many others about the ways scientists watch, listen and learn — at www.lssfzb.com