Sometimes, the improbable happens. The stock market crashes. A big earthquake shakes a city. A nuclear power plant has a meltdown. These seemingly unpredictable, rare incidents — dubbed black swan events — may be unlikely to happen on any specific day, but they do occur. And even though they may be rare, we take precautions. A smart investor balances their portfolio. A California homeowner stores an earthquake preparedness kit in the closet. A power plant designer builds in layers of safeguards.

Conservation managers should be doing the same thing, scientists warn. Black swan events happen among animals, too, and they rarely have positive effects, a new study finds.

How often do black swan events impact animals? To find out, Sean Anderson of the University of Washington in Seattle and colleagues looked at data for 609 populations of birds, mammals and insects. Often, the data were noisy; there could be lots of ups and downs in population sizes, not always with good explanations for what happened. But, Anderson notes, “it turns out that there are plenty of black swan events that are so extreme that we can easily detect them with available data.”

The researchers looked for upswings or declines that were so big they would be observed only once every 10,000 years. For example, the team found a population of gray herons in England that experienced large die-offs in the 1920s, ’40s and ’60s. Those declines were well outside the normal ups and downs found in the population. Harsh winters meant limited food availability for the birds, and the population crashed several times. “The last event actually involved population crashes two years in a row, and it took three times longer for the population to recover than expected,” Anderson notes.

About 4 percent of the populations in the study experienced a black swan event, the team reports in the March 21 Proceedings of the National Academy of Sciences. And this was usually a sharp decline in population size. That’s because there are limits to how fast a population can grow — organisms can only have so many babies per year. But there are no limits to how fast the members of a group can die.

Whether that 4 percent figure holds for the entire animal world is hard to tell. But it does confirm that these events do happen and that they are rarely good. And, given the nature of the events that disrupted populations, it’s possible they may become more common due to climate change.

“We found that most black swan events were caused by things like extreme climate or disease, and often an unexpected combination of factors,” Anderson says. Climate change is expected to increase the frequency and magnitude of events such as heat waves and drought. “We may observe more black swan events in animal populations in the future because of these climate extremes,” he says.
Conservationists can’t predict when such events will happen, but there are ways to minimize their impact when they do, Anderson and colleagues suggest. For animals, this could mean making sure a population doesn’t get so small that something like a disease outbreak — such as the one that happened with saiga antelope in 2015 — or a really bad winter results in extinction.

A handful of measurements of decaying particles has seemed slightly off-kilter for years, intriguing physicists. Now a new decay measurement at the Large Hadron Collider in Geneva has amplified that interest into tentative enthusiasm, with theoretical physicists proposing that weird new particles could explain the results. Scientists with the LHCb experiment reported the new result on April 18 in a seminar at the European particle physics lab CERN, which hosts the LHC.

“It’s incredibly exciting,” says theoretical physicist Benjamin Grinstein of the University of California, San Diego. The new measurement is “a further hint that there’s something new and unexpected happening in very fundamental interactions.”
Other physicists, however, are more cautious, betting that the series of hints will not lead to a new discovery. “One should always remain suspicious of an effect that does not show up in a clear way” in any individual measurement, Carlos Wagner of the University of Chicago wrote in an e-mail.

Taken in isolation, none of the measurements rise beyond the level that can be explained by a statistical fluctuation, meaning that the discrepancies could easily disappear with more data. But, says theoretical physicist David London of the University of Montreal, there are multiple independent hints, “and they all seem to be pointing at something.”

The measurements all involve a class of particle called a B meson, which can be produced when protons are smashed together in the LHC. When a B meson decays, it can produce a type of particle called a kaon that is accompanied either by an electron and a positron (an antimatter version of an electron) or by a muon — the electron’s heavier cousin — and an antimuon.

According to physicists’ accepted theories, muons and electrons should behave essentially identically aside from the effects of their differing masses. That means the two kinds of particles should have an even chance of being produced in such B meson decays. But in the new result, the scientists found only about seven decays with muons for every 10 with electrons.

There are several varieties of B mesons. All are made up of one quark — a type of fundamental particle that also makes up protons and neutrons — and one antiquark. One of the two particles is a type called a “bottom” quark (or antiquark), hence the B meson’s name.
Earlier measurements of another variety of B meson decay also found a muon shortage. What’s more, measurements of the angles at which particles are emitted in some types of B meson decay also appear slightly out of whack, adding to the sense that something funny may be going on in such decays.

“We are excited by how [the measurements] all seem to fit together,” says LHCb spokesperson Guy Wilkinson, an experimental physicist at the University of Oxford in England. If more data confirm that B mesons misbehave, a likely explanation would be a new particle that interacts differently with muons than it does with electrons. One such particle could be a leptoquark — a particle that acts as a bridge between quarks and leptons, the class of particle that includes electrons and muons. Or it could be a heavy, electrically neutral particle called a Z-prime boson.

Physicists spawned a similar hubbub in 2016, when the ATLAS and CMS experiments at the LHC saw hints of a potential new particle that decayed to two photons (SN: 5/28/16, p. 11). Those hints evaporated with more data, and the current anomalies could do likewise. Although the two sets of measurements are very different, says Wolfgang Altmannshofer of the University of Cincinnati, “from the point of the overall excitement, I would say the two things are roughly comparable.”

Luckily, LHCb scientists still have a lot more data to dig into. The researchers used particle collisions only from before 2013, when the LHC was running at lower energy than it is now. “We have to get back to the grindstone and try and analyze more of the data we have,” says Wilkinson. Updated results could be ready in about half a year, he says, and should allow for a more definitive conclusion.

Mapping the relationships between different dog breeds is rough (get it?), but a team of scientists at the National Institutes of Health did just that using the DNA of 1,346 dogs from 161 breeds. Their analysis, which appears April 25 in Cell Reports, offers a lot to chew on.

Here are five key findings from the work:

Dogs were bred for specific jobs, and this shows in their genes.
As human lifestyles shifted from hunting and gathering to herding to agriculture and finally urbanization, humans bred dogs (Canis familiaris) accordingly. Then over the last 200 years, more and more breeds emerged within those categories. Humans crossed breeds to create hybrids based on appearance and temperament, and those hybrids eventually became new breeds.

DNA from hybrid dogs backs up historical records.
Genetic backtracking indicates that, for example, mixing between bulldogs and terriers traces back to Ireland between 1860 and 1870. That timeframe and location coincides with historical records indicating a dog-fighting fad that’s linked with crossing breeds to make better fighters.

Geography also matters.
While herder dog breeds showed a lot of genetic diversity, they fall into two general groups from the rural United Kingdom and the Mediterranean on the breed family tree. When humans switched from hunting to farming, herding breeds may have emerged independently in different areas. Geography could also explain why these two groups use different herding tactics.

New World dogs aren’t all immigrants.
A genetic legacy of America’s early canine inhabitants lives on in some of today’s breeds. Dogs trekked to the Americas from Asia with people more than 10,000 years ago, but when European groups started to colonize the Americas, they brought European dog breeds with them. Past studies suggest that outside breeds largely replaced New World dogs, but the new dataset shows New World dog DNA actually does persist in a few modern New World breeds, such as Chihuahuas.

Big dogs evolved independently to be big.
European mastiffs and Mediterranean sheepdogs don’t share recent changes in their DNA, meaning their size traits arose separately and for different reasons. While both breed groups specialize in guarding things, mastiffs use their size to intimidate humans, while sheepdogs use their size to overpower animal predators. Larger size may have been one of the first traits that human breeders zeroed in on, the researchers suspect.

Leave it to a researcher who studies icy moons in the outer solar system to come up with an out-there scheme to restore vanishing sea ice in the Arctic.

Ice is a good insulator, says Steven Desch, a planetary scientist at Arizona State University in Tempe. That’s why moons such as Jupiter’s Europa and Saturn’s Enceladus, among others, may be able to maintain liquid oceans beneath their thick icy surfaces. On Earth, sea ice is much thinner, but the physics is the same. Ice grows on the bottom surface of floating floes. As the water freezes, it releases heat that must make its way up through the ice before escaping into the air. The thicker the ice, the more heat gets trapped, which slows down ice formation. That’s bad news for the Arctic, where ice helps keep the planet cool but global warming is causing ice to melt faster than it can be replaced.
The answer to making thicker ice more quickly? Suck up near-freezing water from under the ice and pump it directly onto the ice’s surface during the long polar winter. There, the water would freeze more quickly than underneath the ice, where it usually forms.

In theory, Desch says, the pumps used for this top-down approach to ice growth could be driven by technology no more sophisticated than the windmills that have long provided water to farms and ranches on the Great Plains.
Desch and colleagues envision putting such pumps on millions of buoys throughout the Arctic. During winter, each pump would be capable of building an additional layer of sea ice up to 1 meter thick over an area of about 100,000 square meters, or about the size of 15 soccer fields, the researchers estimate in the January issue of Earth’s Future.
It won’t be easy. The Arctic’s harsh environment poses many problems such as frozen pipes. But many of those hitches are being addressed by engineers familiar with developing and maintaining Arctic infrastructure such as small-scale wind turbines and drinking-water systems, Desch says. To build and ship each ice-making buoy to the Arctic would cost about $50,000, he estimates. Over a decade, covering 10 percent of the Arctic Ocean with buoys would cost about $50 billion per year. “It’s a big project, but the point is, it’s not an impossible one,” he argues.

Now is the time to begin detailed designs and build prototypes, Desch says. The Arctic Ocean’s end-of-summer sea ice coverage has decreased, on average, more than 13 percent per decade since 1979. “There’ll be a time, 10 to 15 years from now, when Arctic sea ice will be accelerating to oblivion, and there’ll be political will to do something about climate change,” Desch says. “We need to have this figured out by the time people are ready to do something.”

A wearable robot could prevent future falls among those prone to stumbles.

The new exoskeleton packs motors on a user’s hips and can sense blips in balance. In a small trial, the pelvic robot performed well in sensing and averting wearers’ slips, researchers report May 11 in Scientific Reports.

Exoskeletons have the potential to help stroke victims and people with spinal cord injuries walk again (SN: 11/16/13, p. 22) — and even kick soccer goals (SN Online: 6/12/14). But this new model focuses on a more ordinary aspect of the human condition: falling on your face or your rear. “Exoskeletons could really help in this case,” says study coauthor Silvestro Micera, an engineer at École Polytechnique Fédérale de Lausanne in Switzerland.
Most exoskeletons guide the movement of the wearer, forcing the person to walk in a particular way. But the new pelvic device allows the user to walk normally and reacts only when it needs to. A computer algorithm measures changes in a wearer’s hip joint angles to detect the altered posture that goes along with slipping. The robot then uses its motors to push the hips back into their natural position to, hopefully, prevent a fall.

At a rehab facility in Florence, eight elderly people and two amputees — two groups at risk for balance issues — tried out the device while walking on a treadmill. The robot picked up on slips within 0.35 seconds of a change of gait.

Still, the device has some hurdles ahead. The exoskeleton is bulky, so Micera and his team are working on a sleeker model that would be less imposing for elderly users. The team is also testing the robot’s skills in other types of balance loss like tripping.

Walter A. Feibelman of the University of Pittsburgh … has found evidence indicating a fourth ring [of Saturn].… Every 14.78 years, the rings of Saturn can be seen edge-on from Earth, and the past winter marked one of these opportunities.… The thin ring “extends to more than twice the known ring diameter” (or a total of 340,000 miles), and is so faint it cannot be photographed except with a large telescope. — Science News, June 3, 1967

Update
Scientists no longer observe Saturn’s rings only from Earth. Four spacecraft have visited the planet and revealed a complex ring system, with the four previously known rings accompanied by multiple fainter ones. NASA’s Cassini spacecraft, which arrived at the planet in 2004, is now swooping between Saturn and its rings to get the closest views yet (SN Online: 4/27/17). Rings have also been spied around Jupiter, Uranus and Neptune, and in 2012, scientists spotted an exoplanet with giant rings (SN: 3/7/15, p. 5).

When my girls were newborns, I spent a lot of time damp. Fluids were everywhere, some worse than others. One of the main contributors was milk, which, in various stages of digestion, came back to haunt me in a sloppy trail down my back.

I was sometimes alarmed at the volume of fluid that came flying out of my tiny babies. And I remember asking our pediatrician if it was a problem. We were lucky in that the amount and frequency of the regurgitations didn’t seem to signal trouble.

But some babies spit up a lot more, and seem to be in distress while doing so. That’s led doctors to prescribe antacids to treat reflux disease in these infants. A U.S.-based survey found that from 2000 to 2003, infant use of a type of antacid called proton-pump inhibitors quadrupled.

Those numbers point to worried doctors and parents who want to help babies feel better. The problem, though, is that antacids come with side effects. Mucking with acid levels can affect the body beyond the stomach, and these unintended effects may be even more meddlesome in babies.

“What we found in adults and what we’re starting to see more in children is that [the drugs] are not as benign as we used to think,” says U.S. Air Force Captain Laura Malchodi, a pediatrician at Walter Reed National Military Medical Center in Bethesda, Md.

Infants who took proton-pump inhibitors, a class of drugs that includes Prilosec and Nexium, in their first six months of life broke more bones over the next several years than children who didn’t receive the drugs. That example comes from research Malchodi presented May 7 at the 2017 Pediatric Academic Societies Meeting in San Francisco.

Malchodi and her colleagues examined medical records of nearly 900,000 healthy children. Of those, about 7,000 were prescribed proton-pump inhibitors by the time they were 6 months old. About 67,000 were prescribed histamine H2-blocking drugs, such as Zantac or Pepcid, and about 11,000 babies were prescribed both types of drugs.
Children who had received proton-pump inhibitors, either alone or in combination with a histamine H2-blocker, had more fractures over the next five years than children who weren’t prescribed that type of drug. The researchers tried to rule out other differences between the groups of babies that might explain the higher number of fractures. When those differences were removed from the analysis, proton-pump inhibitor prescriptions were still linked to fractures.

The study can’t say whether proton-pump inhibitors definitely caused weaker bones. But that’s not an unreasonable hypothesis given what’s seen in adults, for whom the link between long-term use of proton-pump inhibitors and broken bones is stronger.

If proton-pump inhibitors do interfere with bones, it’s still a mystery exactly how. One idea was that the drugs hinder calcium absorption, leading to weaker bones. That idea has fallen out of favor, Malchodi says. Another proposal centers on cells called osteoclasts. To do their job, these cells rely on proton pumps to create acidic pockets around bones. But if osteoclasts aren’t working properly, “in the end, what you get is disorganized bone,” Malchodi says.

Reflux disease is not the same thing as reflux, which babies are nearly guaranteed to experience. For one thing, the amount of liquid they’re slurping down relative to their body weight is huge. And that liquid is held down by an esophageal sphincter that’s often underdeveloped in babies. (One technical term for reflux is “poor gastric compliance,” but I bet you’ve got more colorful descriptions.)

Antacids won’t stop babies from spitting up, says Malchodi. “We definitely counsel parents all the time that this is not going to stop the reflux,” she says. Instead, the drugs are thought to change the pH of the liquid coming back up in an attempt to make it less irritating.

Some babies may need that pharmaceutical help. But many may not. If babies are growing well and don’t seem to be in long-lasting distress, then it’s possible that they may need the “tincture of time” to outgrow the reflux. (Malchodi points out that so-called “happy spitters” are probably not smiling while they’re barfing, because obviously, throwing up is not fun. It’s just that these babies don’t seem to be bothered long after the spitting.)

She hopes that her research and other studies like it will prompt more careful discussions between parents and doctors before antacids are prescribed. And if they are deemed necessary, “have a stop point in mind,” she says.

For centuries, skywatchers have reported seeing and simultaneously hearing meteors whizzing overhead, which doesn’t make sense given that light travels roughly 800,000 times as fast as sound. Now scientists say they have a potential explanation for the paradox.

The sound waves aren’t coming from the meteor itself, atmospheric scientists Michael Kelley of Cornell University and Colin Price of Tel Aviv University propose April 16 in Geophysical Research Letters. As the leading edge of the falling space rock vaporizes, it becomes electrically charged. The charged head produces an electric field, which yields an electric current that blasts radio waves toward the ground. As a type of electromagnetic radiation, radio waves travel at the speed of light and can interact with metal objects near the ground, generating a whistling sound that people can hear.

Just 0.1 percent of the radio wave energy needs to be converted into sound for the noise to be audible as the meteor zips by, the researchers estimate. This same process could explain mysterious noises heard during the aurora borealis, or northern lights (SN: 8/9/14, p. 32). Like meteors, auroras have been known to emit radio wave bursts.

The planet KELT 9b is so hot — hotter than many stars — that it shatters gas giant temperature records, researchers report online June 5 in Nature.

This Jupiter-like exoplanet revolves around a star just 650 light-years away, locked in an orbit that keeps one side always facing its star. With blistering temps hovering at about 4,300o Celsius, the atmosphere on KELT 9b’s dayside is over 700 degrees hotter than the previous record-holder — and hot enough that atoms cannot bind together to form molecules.
“It’s like a star-planet hybrid,” says Drake Deming, a planetary scientist at the University of Maryland in College Park who was not involved in the research. “A kind of object we’ve never seen before.”

KELT 9b also boasts an unusual orbit, travelling around the poles of its star, rather than the equator, once every 36 hours. And radiation from KELT 9b’s host star is so intense that it blows the planet’s atmosphere out like a comet tail — and may eventually strip it away completely.

The planet is so bizarre that it took scientists nearly three years to convince themselves it was real, says Scott Gaudi of Ohio State University. Deming suspects KELT 9b is “the tip of the iceberg” for an undiscovered population of scalding-hot gas giants.

Jupiter was an early bloomer. New measurements of meteorite ages suggest that the giant planet’s core must have formed within the solar system’s first million years. If so, Jupiter’s presence could help explain why the inner planets are so small — and possibly even be responsible for Earth’s existence.

Previously, astronomers’ best constraints on Jupiter’s age came from simulations of how solar systems form in general. Gas giants like Jupiter grow by accreting gas from spinning disks of gas and dust around a young star. Those disks typically don’t last more than 10 million years, so astronomers inferred that Jupiter formed by the time that disk dissipated.
“Now we can use actual data from the solar system to show Jupiter formed even earlier,” says Thomas Kruijer, who did the research while at the University of Münster in Germany. Kruijer, now at Lawrence Livermore National Laboratory in California, and his team report Jupiter’s new age in the Proceedings of the National Academy of Sciences the week of June 12.

To study one of the biggest objects in the solar system, Kruijer and colleagues turned to some of the smallest: meteorites. Most meteorites come from the asteroid belt currently located between Mars and Jupiter but probably were born elsewhere.

Luckily, meteorites carry a signature of their birthplaces. The gas and dust disk that the planets formed from had different neighborhoods. Each had its own “zip code,” areas enriched in certain isotopes, or different masses of the same elements. Careful measurements of a meteorite’s isotopes can point to its home.

Kruijer and colleagues selected 19 samples of rare iron meteorites from the Natural History Museum in London and the Field Museum in Chicago. These rocks represent the metal cores of the first asteroid-like bodies to congeal as the solar system was forming.

The team dissolved about a gram of each sample in a solution of nitric acid and hydrochloric acid. “It smells terrible,” Kruijer says.
Then the researchers separated out the elements tungsten — a good tracer of both a meteorite’s age and birthplace — and molybdenum, another tracer of a meteorite’s home.

By measuring the relative amounts of molybdenum-94, molybdenum-95, tungsten-182 and tungsten-183, Kruijer and his team identified two distinct groups of meteorites. One group formed closer to the sun than Jupiter is today; the other formed farther from the sun.

The tungsten isotopes also showed that both groups existed at the same time, between about 1 million and 4 million years after the start of the solar system about 4.57 billion years ago (SN Online: 8/23/10). That means something must have kept them separated.

The most likely candidate is Jupiter, Kruijer says. His team’s calculations suggest that Jupiter’s core had probably grown to about 20 times the mass of the Earth in the solar system’s first million years, making it the oldest planet. Its presence would have created a gravitational barrier that kept the two meteorite neighborhoods segregated. Jupiter would then have continued growing at a slower rate for the next few billion years.

“I have high confidence that their data is excellent,” says cosmochemist Meenakshi Wadhwa of Arizona State University in Tempe. The suggestion that Jupiter held the different meteorites apart is “a little more speculative, but I buy it,” she adds.

Jupiter’s early entrance could also explain why the inner solar system lacks any planets larger than Earth. Many extrasolar planetary systems have large close-in planets, from rocky super-Earths (about two to 10 times the mass of Earth) to gassy mini-Neptunes or hot Jupiters. Astronomers have puzzled over why our solar system looks so different.

An early Jupiter’s gravity could have kept most of the planet-forming disk away from the sun, meaning there was less raw material for the inner planets. This picture is consistent with other work suggesting a young Jupiter wandered through the inner solar system and swept it clean (SN: 4/2/16, p.7), Kruijer says.

“Without Jupiter, we could have had Neptune where Earth is,” Kruijer says. “And if that’s the case, there would probably be no Earth.”