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Inspired by how ants move through narrow spaces by shortening their legs, scientists have built a robot that draws in its limbs to navigate constricted passages.

The robot was able to hunch down and walk quickly through passages that were narrower and shorter than itself, researchers report January 20 in Advanced Intelligent Systems. It could also climb over steps and move on grass, loose rock, mulch and crushed granite.

Such generality and adaptability are the main challenges of legged robot locomotion, says robotics engineer Feifei Qian, who was not involved in the study. Some robots have specialized limbs to move over a particular terrain, but they cannot squeeze into small spaces (SN: 1/16/19).
“A design that can adapt to a variety of environments with varying scales or stiffness is a lot more challenging, as trade-offs between the different environments need to be considered,” says Qian, of the University of Southern California in Los Angeles.

For inspiration, researchers in the new study turned to ants. “Insects are really a neat inspiration for designing robot systems that have minimal actuation but can perform a multitude of locomotion behaviors,” says Nick Gravish, a roboticist at the University of California, San Diego (SN: 8/16/18). Ants adapt their posture to crawl through tiny spaces. And they aren’t perturbed by uneven terrain or small obstacles. For example, their legs collapse a bit when they hit an object, Gravish says, and the ants continue to move forward quickly.

Gravish and colleagues built a short, stocky robot — about 30 centimeters wide and 20 centimeters long — with four wavy, telescoping limbs. Each limb consists of six nested concentric tubes that can draw into each other. What’s more, the limbs do not need to be actively powered or adjusted to change their overall length. Instead, springs that connect the leg segments automatically allow the legs to contract when the robot navigates a narrow space and stretch back out in an open space. The goal was to build mechanically intelligent structures rather than algorithmically intelligent robots.

“It’s likely faster than active control, [which] requires the robot to first sense the contact with the environment, compute the suitable action and then send the command to its motors,” Qian says, about these legs. Removing the sensing and computing components can also make the robots small, cheap and less power hungry.

The robot could modify its body width and height to achieve a larger range of body sizes than other similar robots. The leg segments contracted into themselves to let the robot wiggle through small tunnels and sprawled out when under low ceilings. This adaptability let the robot squeeze into spaces as small as 72 percent its full width and 68 percent its full height.
Next, the researchers plan to actively control the stiffness of the springs that connect the leg segments to tune the motion to terrain type without consuming too much power. “That way, you can keep your leg long when you are moving on open ground or over tall objects, but then collapse down to the smallest possible shape in confined spaces,” Gravish says.
Such small-scale, minimal robots are easy to produce and can be quickly tweaked to explore complex environments. However, despite being able to walk across different terrains, these robots are, for now, too fragile for search-and-rescue, exploration or biological monitoring, Gravish says.

The new robot takes a step closer to those goals, but getting there will take more than just robotics, Qian says. “To actually achieve these applications would require an integration of design, control, sensing, planning and hardware advancement.”

But that’s not Gravish’s interest. Instead, he wants to connect these experiments back to what was observed in the ants originally and use the robots to ask more questions about the rules of locomotion in nature (SN: 1/16/20).

“I really would like to understand how small insects are able to move so rapidly across certain unpredictable terrain,” he says. “What is special about their limbs that enables them to move so quickly?”

The dwarf planet Quaoar has a ring that is too big for its metaphorical fingers. While all other rings in the solar system lie within or near a mathematically determined distance of their parent bodies, Quaoar’s ring is much farther out.

“For Quaoar, for the ring to be outside this limit is very, very strange,” says astronomer Bruno Morgado of the Federal University of Rio de Janeiro. The finding may force a rethink of the rules governing planetary rings, Morgado and colleagues say in a study published February 8 in Nature.
Quaoar is an icy body about half the size of Pluto that’s located in the Kuiper Belt at the solar system’s edge (SN: 8/23/22). At such a great distance from Earth, it’s hard to get a clear picture of the world.

So Morgado and colleagues watched Quaoar block the light from a distant star, a phenomenon called a stellar occultation. The timing of the star winking in and out of view can reveal details about Quaoar, like its size and whether it has an atmosphere.

The researchers took data from occultations from 2018 to 2020, observed from all over the world, including Namibia, Australia and Grenada, as well as space. There was no sign that Quaoar had an atmosphere. But surprisingly, there was a ring. The finding makes Quaoar just the third dwarf planet or asteroid in the solar system known to have a ring, after the asteroid Chariklo and the dwarf planet Haumea (SN: 3/26/14; SN: 10/11/17).

Even more surprisingly, “the ring is not where we expect,” Morgado says.
Known rings around other objects lie within or near what’s called the Roche limit, an invisible line where the gravitational force of the main body peters out. Inside the limit, that force can rip a moon to shreds, turning it into a ring. Outside, the gravity between smaller particles is stronger than that from the main body, and rings will coalesce into one or several moons.

“We always think of [the Roche limit] as straightforward,” Morgado says. “One side is a moon forming, the other side is a ring stable. And now this limit is not a limit.”

For Quaoar’s far-out ring, there are a few possible explanations, Morgado says. Maybe the observers caught the ring at just the right moment, right before it turns into a moon. But that lucky timing seems unlikely, he notes.

Maybe Quaoar’s known moon, Weywot, or some other unseen moon contributes gravity that holds the ring stable somehow. Or maybe the ring’s particles are colliding in such a way that they avoid sticking together and clumping into moons.

The particles would have to be particularly bouncy for that to work, “like a ring of those bouncy balls from toy stores,” says planetary scientist David Jewitt of UCLA, who was not involved in the new work.

The observation is solid, says Jewitt, who helped discover the first objects in the Kuiper Belt in the 1990s. But there’s no way to know yet which of the explanations is correct, if any, in part because there are no theoretical predictions for such far-out rings to compare with Quaoar’s situation.

That’s par for the course when it comes to the Kuiper Belt. “Everything in the Kuiper Belt, basically, has been discovered, not predicted,” Jewitt says. “It’s the opposite of the classical model of science where people predict things and then confirm or reject them. People discover stuff by surprise, and everyone scrambles to explain it.”

More observations of Quaoar, or more discoveries of seemingly misplaced rings elsewhere in the solar system, could help reveal what’s going on.

“I have no doubt that in the near future a lot of people will start working with Quaoar to try to get this answer,” Morgado says.

Among some killer whale moms, lifelong feeding for adult sons but not daughters could be a long-term investment play. The delayed payoff? Greater grandmotherly glory.

Females in a quirky population of killer whales off the Pacific Coast of North America let their grown mama’s boys share fish that mom catches. Biologists have known that this pampering continues throughout a son’s life, which can last decades. Grown daughters, often feeding their own offspring, however, don’t get such a bonus.
Scrutinizing decades of data has now revealed what moms sacrifice to lavish a lifetime of food on a son, researchers report February 8 in Current Biology. A mother’s yearly chance of successfully weaning a calf drops by about half after she has a son, says behavioral ecologist Michael Weiss of the Center for Whale Research in Friday Harbor, Wash.

For the moms, “it’s a huge, huge cost that they’re taking on,” Weiss says. It “emphasizes kind of the uniqueness and the intensity of this mother-son bond in killer whales.” For creatures that bear their young in a series, he says, this finding is “our first kind of direct evidence of any animal showing lifetime parental investment.”

These killer whales off the coast of Washington State and British Columbia, in “the southern resident” population of Orcinus orca, don’t migrate. Instead they specialize in feeding year-round on the region’s fish, such as big chinook salmon.

When moms catch a fish, “they do this huge head jerk, and one half of the fish stays in the mouth and the other half kind of trails behind them as they swim on,” Weiss says. A son swimming with her can then grab that other half. “It’s not the son coming up and grabbing the fish out of her mouth,” he says.

The son’s company looks consensual to Weiss. Mothers and sons “spend a lot of time kind of floating at the surface together … just kind of enjoying each other’s company.” Whale watchers need to take care reading interpretations into behavior, he says, but his “intuition from watching them is more about the mom wanting to provide for the son.”

Weiss doesn’t think the decline in new births after producing a son comes from any lack of opportunity to mate. “These whales are really social,” he says. “They’re usually in quite large groups, and usually with at least one sexually mature male around.” When watching them from drones, “we see that social behavior in these whales often involves a lot of sexual behavior,” he says. Nevertheless, all those halved fishes may not give a mom enough nutrition for the demands of whale pregnancy.

Mom’s grandchild tally however can make up for her own limited reproduction as she coddles her sons, the whale records show. Sons don’t have to parent. They just deliver sperm to the right address. Plus, the longer males live, the better, Weiss says. For a few years, genetics suggested that the two oldest males in the southern resident population were siring more than half the new calves.
Female killer whales, however, face more constraints. Killer whale pregnancies last some 18 months. So a Casanova whale’s sister gets preoccupied for a long time producing just one wrinkly not-so-little darling and then nurturing it to independence.

Female killer whales do have a chance to help later generations survive, because the species is among the few nonhuman mammals that experience menopause (SN: 3/5/15; SN: 8/19/13). (Females can stop reproducing in their 30s or 40s, but can live into their 80s).

Whether moms in other killer whale populations also routinely and consequentially serve dinner for grown sons isn’t an easy question to answer. Weiss wonders whether the same male whales in another place, perhaps with more abundant fish, would still reduce their mothers’ success at later births.

No other killer whale population’s records can match the depth of the ones Weiss used, says cetacean biologist Eve Jourdain of the University of Oslo. Her research focuses on killer whales around Norway that follow the seasonal movements of herring and other food bonanzas.

Jourdain doesn’t recall moms flinging fish, but she watches the whales herding local herring into big fish balls of swimming dinner. Which they share. So there may be other kinds of food-based bonding yet to be analyzed.

If you’re a museum aficionado itching for a new place to explore, 2023 has you covered. New science museums and exhibitions are opening, and some zoos are expanding. This sampling of destinations to check out in the new year or beyond has something for everyone, whether you’re a wildlife lover, space nerd or history buff.

Grand Egyptian Museum
Outside Cairo
Opens: To be announced

2022 marked the 100th anniversary of the discovery of King Tut’s tomb (SN: 11/19/22, p. 14). Now, thousands of artifacts from the tomb — along with tens of thousands of other archaeological finds from ancient Egypt — will go on display when this museum, located within view of the Pyramids of Giza, opens. More than a decade in the making, it will be one of the largest archaeological museums in the world.
Richard Gilder Center for Science, Education and Innovation
American Museum of Natural History
New York City
Opens: February 17

This multistory building will add tons of new exhibit space to the more than 150-year-old museum. Visitors can explore an insectarium that includes one of the world’s largest displays of live leaf-cutting ants and come face-to-face with dozens of butterfly species in a vivarium. Meanwhile, the interconnectedness of life will be on display in the immersive, 360-degree “Invisible Worlds” exhibition.
Galápagos Islands
Houston Zoo
Opens: April 2023

If you can’t travel to the Galápagos Islands, a trip to Texas might be the next best thing. Giant tortoises, iguanas, penguins, sea lions, sharks and other creatures will inhabit this new exhibition that will re-create the land and marine ecosystems of the archipelago made famous by Charles Darwin.

Kansas City Zoo Aquarium
Opens: September 2023

The 34 exhibits of this new aquarium will allow visitors to glimpse a wide variety of ocean locales without having to leave the Midwest. Underwater residents will include sea urchins and sea anemones in a warm intertidal zone, fish swimming in a coral reef, comb jellies floating in the open ocean and sea otters playing along a rocky shore.
SPACE
Franklin Institute
Philadelphia
Opens: Fall 2023

To design this new two-story gallery dedicated to the future of space exploration, exhibit planners met with local students and teachers to find out what they wanted to learn. The result is an experience that, among other things, will showcase the current and future technologies needed to live and work in space as well as the many career paths into the aerospace industry.
Bird House
Smithsonian’s National Zoo
Washington, D.C.
Opens: To be announced

With a focus on bird migration and conservation in the Americas, the zoo’s new bird house will feature three aviaries: The first will show how the Delaware Bay is a key refueling spot for migratory shorebirds, the second will demonstrate how seasonal wetlands in the Midwest serve waterfowl and the third will illustrate how a tropical coffee farm can provide respite for songbirds in winter.
Robot & AI Museum
Seoul, South Korea
Opens: To be announced

Though details are still scant, this museum dedicated to furthering public knowledge of robotics, artificial intelligence and machine learning is expected to open later this year.

For nearly 650 years, the fortress walls in the Chinese city of Xi’an have served as a formidable barrier around the central city. At 12 meters high and up to 18 meters thick, they are impervious to almost everything — except subatomic particles called muons.

Now, thanks to their penetrating abilities, muons may be key to ensuring that the walls that once protected the treasures of the first Ming Dynasty — and are now a national architectural treasure in their own right — stand for centuries more.

A refined detection method has provided the highest-resolution muon scans yet produced of any archaeological structure, researchers report in the Jan. 7 Journal of Applied Physics. The scans revealed interior density fluctuations as small as a meter across inside one section of the Xi’an ramparts. The fluctuations could be signs of dangerous flaws or “hidden structures archaeologically interesting for discovery and investigation,” says nuclear physicist Zhiyi Liu of Lanzhou University in China.
Muons are like electrons, only heavier. They rain down all over the planet, produced when charged particles called cosmic rays hit the atmosphere. Although muons can travel deep into earth and stone, they are scattered or absorbed depending on the material they encounter. Counting the ones that pass through makes them useful for studying volcano interiors, scanning pyramids for hidden chambers and even searching for contraband stashed in containers impervious to X-rays (SN: 4/22/22).

Though muons stream down continuously, their numbers are small enough that the researchers had to deploy six detectors for a week at a time to collect enough data for 3-D scans of the rampart.

It’s now up to conservationists to determine how to address any density fluctuations that might indicate dangerous flaws, or historical surprises, inside the Xi’an walls.

High-tech shrink art may be the key to making tiny electronics, 3-D nanostructures or even holograms for hiding secret messages.

A new approach to making tiny structures relies on shrinking them down after building them, rather than making them small to begin with, researchers report in the Dec. 23 Science.

The key is spongelike hydrogel materials that expand or contract in response to surrounding chemicals (SN: 1/20/10). By inscribing patterns in hydrogels with a laser and then shrinking the gels down to about one-thirteenth their original size, the researchers created patterns with details as small as 25 billionths of a meter across.
At that level of precision, the researchers could create letters small enough to easily write this entire article along the circumference of a typical human hair.

Biological scientist Yongxin Zhao and colleagues deposited a variety of materials in the patterns to create nanoscopic images of Chinese zodiac animals. By shrinking the hydrogels after laser etching, several of the images ended up roughly the size of a red blood cell. They included a monkey made of silver, a gold-silver alloy pig, a titanium dioxide snake, an iron oxide dog and a rabbit made of luminescent nanoparticles.
Because the hydrogels can be repeatedly shrunk and expanded with chemical baths, the researchers were also able to create holograms in layers inside a chunk of hydrogel to encode secret information. Shrinking a hydrogel hologram makes it unreadable. “If you want to read it, you have to expand the sample,” says Zhao, of Carnegie Mellon University in Pittsburgh. “But you need to expand it to exactly the same extent” as the original. In effect, knowing how much to expand the hydrogel serves as a key to unlock the information hidden inside.

But the most exciting aspect of the research, Zhao says, is the wide range of materials that researchers can use on such minute scales. “We will be able to combine different types of materials together and make truly functional nanodevices.”

Today’s red jungle fowl — the wild forebears of the domesticated chicken — are becoming more chickenlike. New research suggests that a large proportion of the wild fowl’s DNA has been inherited from chickens, and relatively recently.

Ongoing interbreeding between the two birds may threaten wild jungle fowl populations’ future, and even hobble humans’ ability to breed better chickens, researchers report January 19 in PLOS Genetics.

Red jungle fowl (Gallus gallus) are forest birds native to Southeast Asia and parts of South Asia. Thousands of years ago, humans domesticated the fowl, possibly in the region’s rice fields (SN: 6/6/22).
“Chickens are arguably the most important domestic animal on Earth,” says Frank Rheindt, an evolutionary biologist at the National University of Singapore. He points to their global ubiquity and abundance. Chicken is also one of the cheapest sources of animal protein that humans have.

Domesticated chickens (G. gallus domesticus) were known to be interbreeding with jungle fowl near human settlements in Southeast Asia. Given the unknown impacts on jungle fowl and the importance of chickens to humankind, Rheindt and his team wanted to gather more details. Wild jungle fowl contain a store of genetic diversity that could serve as a crucial resource for breeding chickens resistant to diseases or other threats.

The researchers analyzed and compared the genomes — the full complement of an organism’s DNA — of 63 jungle fowl and 51 chickens from across Southeast Asia. Some of the jungle fowl samples came from museum specimens collected from 1874 through 1939, letting the team see how the genetic makeup of jungle fowl has changed over time.

Over the last century or so, wild jungle fowl’s genomes have become increasingly similar to chickens’. Between about 20 and 50 percent of the genomes of modern jungle fowl originated in chickens, the team found. In contrast, many of the roughly 100-year-old jungle fowl had a chicken-ancestry share in the range of a few percent.

The rapid change probably comes from human communities expanding into the region’s wilderness, Rheindt says. Most modern jungle fowl live in close vicinity to humans’ free-ranging chickens, with which they frequently interbreed.

Such interbreeding has become “almost the norm now” for any globally domesticated species, Rheindt says, such as dogs hybridizing with wolves and house cats crossing with wildcats. Pigs, meanwhile, are mixing with wild boars and ferrets with polecats.
Wild populations that interbreed with their domesticated counterparts could pick up physical or behavioral traits that change how the hybrids function in their ecosystem, says Claudio Quilodrán, a conservation geneticist at the University of Geneva not involved with this research.

The effect is likely to be negative, Quilodrán says, since some of the traits coming into the wild population have been honed for human uses, not for survival in the local environment.

Wild jungle fowl have lost their genetic diversity as they’ve interbred too. The birds’ heterozygosity — a measure of a population’s genetic diversity — is now just a tenth of what it was a century ago.

“This result is initially counterintuitive,” Rheindt says. “If you mix one population with another, you would generally expect a higher genetic diversity.”

But domesticated chickens have such low genetic diversity that certain versions of jungle fowl genes are being swept out of the population by a tsunami of genetic homogeneity. The whittling down of these animals’ genetic toolkit may leave them vulnerable to conservation threats.

“Having lots of genetic diversity within a species increases the chance that certain individuals contain the genetic background to adapt to a varied range of different environmental changes and diseases,” says Graham Etherington, a computational biologist at the Earlham Institute in Norwich, England, who was not involved with this research.

A shallower jungle fowl gene pool could also mean diminished resources for breeding better chickens. The genetics of wild relatives are sometimes used to bolster the disease or pest resistance of domesticated crop plants. Jungle fowl genomes could be similarly valuable for this reason.

“If this trend continues unabated, future human generations may only be able to access the entirety of ancestral genetic diversity of chickens in the form of museum specimens,” Rheindt says, which could hamper chicken breeding efforts using the wild fowl genes.

Some countries such as Singapore, Rheindt says, have started managing jungle fowl populations to reduce interbreeding with chickens.

A 120-million-year-old fossil bird found in China could offer some new clues about how landbound dinosaurs evolved into today’s flying birds. The dove-sized Cratonavis zhui sported a dinosaur-like head atop a body similar to those of today’s birds, researchers report in the January Nature Ecology & Evolution.

The flattened specimen came from the Jiufotang Formation, an ancient body of rock in northeastern China that is a hotbed for preserved feathered dinosaurs and archaic birds. CT scans revealed that Cratonavis had a skull that was nearly identical (albeit smaller) as those of theropod dinosaurs like Tyrannosaurus rex, paleontologist Li Zhiheng of the Chinese Academy of Sciences in Beijing and colleagues report. This means that Cratonavis still hadn’t evolved the mobile upper jaw found in modern birds (SN: 5/2/18).
It’s among just a handful of specimens that belong to a recently identified group of intermediate birds known as the jinguofortisids, says Luis Chiappe, a paleontologist at the Natural History Museum of Los Angeles County who was not involved in the study. Its dino-bird mishmash “is not unexpected.” Most birds discovered from the Age of Dinosaurs exhibited more primitive, toothed heads than today’s birds, he says. But the new find “builds on our understanding of this primitive group of birds that are at the base of the tree of birds.”

Cratonavis also had an unusually elongated scapula and hallux, or backward-facing toe. Rarely seen in Cretaceous birds, enlarged shoulder blades might have compensated for the bird’s otherwise underwhelming flight mechanics, the researchers say. And that hefty big toe? It bucks the trend of shrinking metatarsals seen as birds continued to evolve. Cratonavis might have used this impressive digit to hunt like today’s birds of prey, Li’s team says.

Filling those shoes may have been too big of a job for Cratonavis, though. Given its size, Chiappe says, the dino-headed bird would have most likely been a petite hunter, taking down the likes of beetles, grasshoppers and the occasional lizard rather than terrorizing the skies.

The worst procrastinators probably won’t be able to read this story. It’ll remind them of what they’re trying to avoid, psychologist Piers Steel says.

Maybe they’re dragging their feet going to the gym. Maybe they haven’t gotten around to their New Year’s resolutions. Maybe they’re waiting just one more day to study for that test.

Procrastination is “putting off to later what you know you should be doing now,” even if you’ll be worse off, says Steel, of the University of Calgary in Canada. But all those tasks pushed to tomorrow seem to wedge themselves into the mind — and it may be harming people’s health.
In a study of thousands of university students, scientists linked procrastination to a panoply of poor outcomes, including depression, anxiety and even disabling arm pain. “I was surprised when I saw that one,” says Fred Johansson, a clinical psychologist at Sophiahemmet University in Stockholm. His team reported the results January 4 in JAMA Network Open.

The study is one of the largest yet to tackle procrastination’s ties to health. Its results echo findings from earlier studies that have gone largely ignored, says Fuschia Sirois, a behavioral scientist at Durham University in England, who was not involved with the new research.

For years, scientists didn’t seem to view procrastination as something serious, she says. The new study could change that. “It’s that kind of big splash that’s … going to get attention,” Sirois says. “I’m hoping that it will raise awareness of the physical health consequences of procrastination.”

Procrastinating may be bad for the mind and body
Whether procrastination harms health can seem like a chicken-and-egg situation.

It can be hard to tell if certain health problems make people more likely to procrastinate — or the other way around, Johansson says. (It may be a bit of both.) And controlled experiments on procrastination aren’t easy to do: You can’t just tell a study participant to become a procrastinator and wait and see if their health changes, he says.
Many previous studies have relied on self-reported surveys taken at a single time point. But a snapshot of someone makes it tricky to untangle cause and effect. Instead, in the new study, about 3,500 students were followed over nine months, so researchers could track whether procrastinating students later developed health issues.

On average, these students tended to fare worse over time than their prompter peers. They were slightly more stressed, anxious, depressed and sleep-deprived, among other issues, Johansson and colleagues found. “People who score higher on procrastination to begin with … are at greater risk of developing both physical and psychological problems later on,” says study coauthor Alexander Rozental, a clinical psychologist at Uppsala University in Sweden. “There is a relationship between procrastination at one time point and having these negative outcomes at the later point.”

The study was observational, so the team can’t say for sure that procrastination causes poor health. But results from other researchers also seem to point in this direction. A 2021 study tied procrastinating at bedtime to depression. And a 2015 study from Sirois’ lab linked procrastinating to poor heart health.

Stress may be to blame for procrastination’s ill effects, data from Sirois’ lab and other studies suggest. She thinks that the effects of chronic procrastinating could build up over time. And though procrastination alone may not cause disease, Sirois says, it could be “one extra factor that can tip the scales.”

No, procrastinators are not lazy
Some 20 percent of adults are estimated to be chronic procrastinators. Everyone might put off a task or two, but chronic procrastinators make it their lifestyle, says Joseph Ferrari, a psychologist at DePaul University in Chicago, who has been studying procrastination for decades. “They do it at home, at school, at work and in their relationships.” These are the people, he says, who “you know are going to RSVP late.”

Though procrastinators may think they perform better under pressure, Ferrari has reported the opposite. They actually worked more slowly and made more errors than non-procrastinators, his experiments have shown. And when deadlines are slippery, procrastinators tend to let their work slide, Steel’s team reported last year in Frontiers in Psychology.

For years, researchers have focused on the personalities of people who procrastinate. Findings vary, but some scientists suggest procrastinators may be impulsive, worriers and have trouble regulating their emotions. One thing procrastinators are not, Ferrari emphasizes, is lazy. They’re actually “very busy doing other things than what they’re supposed to be doing,” he says.

In fact, Rozental adds, most research today suggests procrastination is a behavioral pattern.

And if procrastination is a behavior, he says, that means it’s something you can change, regardless of whether you’re impulsive.

Why procrastinators should be kind to themselves
When people put off a tough task, they feel good — in the moment.
Procrastinating is a way to sidestep the negative emotions linked to the task, Sirois says. “We’re sort of hardwired to avoid anything painful or difficult,” she says. “When you procrastinate, you get immediate relief.” A backdrop of stressful circumstances — say, a worldwide pandemic — can strain people’s ability to cope, making procrastinating even easier. But the relief it provides is only temporary, and many seek out ways to stop dawdling.

Researchers have experimented with procrastination treatments that run the gamut from the logistical to the psychological. What works best is still under investigation. Some scientists have reported success with time-management interventions. But the evidence for that “is all over the map,” Sirois says. That’s because “poor time management is a symptom not a cause of procrastination,” she adds.

For some procrastinators, seemingly obvious tips can work. In his clinical practice, Rozental advises students to simply put down their smartphones. Silencing notifications or studying in the library rather than at home can quash distractions and keep people on task. But that won’t be enough for many people, he says.

Hard-core procrastinators may benefit from cognitive behavioral therapy. In a 2018 review of procrastination treatments, Rozental found that this type of therapy, which involves managing thoughts and emotions and trying to change behavior, seemed to be the most helpful. Still, not many studies have examined treatments, and there’s room for improvement, he says.

Sirois also favors an emotion-centered approach. Procrastinators can fall into a shame spiral where they feel uneasy about a task, put the task off, feel ashamed for putting it off and then feel even worse than when they started. People need to short-circuit that loop, she says. Self-forgiveness may help, scientists suggested in one 2020 study. So could mindfulness training.

In a small trial of university students, eight weekly mindfulness sessions reduced procrastination, Sirois and colleagues reported in the January Learning and Individual Differences. Students practiced focusing on the body, meditating during unpleasant activities and discussed the best way to take care of themselves. A little self-compassion may snap people out of their spiral, Sirois says.

“You made a mistake and procrastinated. It’s not the end of the world,” she says. “What can you do to move forward?”

Supercooled water is two of a kind, a new study shows.

Scientists have long suspected that water at subfreezing temperatures comes in two distinct varieties: a high-density liquid that appears at very high pressures and a low-density liquid at lower pressures. Now, ultrafast measurements have caught water morphing from one type of liquid to the other, confirming that hunch. The discovery, reported in the Nov. 20 Science, could help explain some of water’s quirks.

The experiment “adds more and more evidence to the idea that water really is two components … and that that is the reason that underlies why water is so weird,” says physicist Greg Kimmel of Pacific Northwest National Laboratory in Richland, Wash., who was not involved in the study.

When free from impurities, water can remain liquid below its typical freezing point of zero degrees Celsius, forming what’s called a supercooled liquid. But the dual nature of supercooled water was expected to appear in a temperature realm so difficult to study that it’s been dubbed “no-man’s-land.” Below around –40° C, water remains liquid for mere instants before it crystallizes into ice. Making the task even more daunting, the high-density phase appears only at very high pressures. Still, “people have dreamt about how to do an experiment,” says Anders Nilsson of Stockholm University.
Thanks to speedy experimental maneuvers, Nilsson and colleagues have infiltrated that no-man’s-land by monitoring water’s properties on a scale of nanoseconds. “This is one of the major accomplishments of this paper,” says computational chemist Gül Zerze of Princeton University. “I’m impressed with their work.”

The scientists started by creating a type of high-density ice. Then, a pulse from an infrared laser heated the ice, forming liquid water under high pressure. That water then expanded, and the pressure rapidly dropped. Meanwhile, the researchers used an X-ray laser to investigate how the structure of the water changed, based on how the X-rays scattered. As the pressure decreased, the water transitioned from a high-density to low-density fluid before crystallizing into ice.

Previous studies have used ultrafast techniques to find hints of water’s two-faced demeanor, but those have been done mainly at atmospheric pressure (SN: 9/28/20). In the new work, the water was observed at about 3,000 times atmospheric pressure and –68° C. “It’s the first time we have real experimental data at these pressures and temperatures,” says physicist Loni Kringle of Pacific Northwest National Laboratory, who was not involved with the experiment.

The result could indicate that supercooled water has a “critical point” — a certain pressure and temperature at which two distinct phases merge into one. In the future, Nilsson hopes to pinpoint that spot.

Such a critical point could explain why water is an oddball liquid. For most liquids, cooling makes them become denser and more difficult to compress. Water gets denser as it is cooled to 4° C, but becomes less dense as it is cooled further. Likewise, its compressibility increases as it’s cooled.

If supercooled water has a critical point, that could indicate that the water experienced in daily life is strange because, under typical pressures and temperatures, it is a supercritical liquid — a weird state that occurs beyond a critical point. Such a liquid would not be the high-density or low-density form, but would consist of some regions with a high-density arrangement of water molecules and other pockets of low density. The relative amounts of those two structures, which result from different arrangements of hydrogen bonds between the molecules, would change as the temperature changes, explaining why water behaves strangely as it is cooled.

So despite the fact that the experiment involved extreme pressures and temperatures, Nilsson says, “it influences water in our ordinary life.”