If you look at a map of the world, it’s easy to think that the vast oceans would be effective barriers to the movement of land animals. And while an elephant can’t swim across the Pacific, it turns out that plenty of plants and animals — and even people — have unintentionally floated across oceans from one continent to another. Now comes evidence that tiny, sedentary trapdoor spiders made such a journey millions of years ago, taking them from Africa all the way across the Indian Ocean to Australia.

Moggridgea rainbowi spiders from Kangaroo Island, off the south coast of Australia, are known as trapdoor spiders because they build a silk-lined burrow in the ground with a secure-fitting lid, notes Sophie Harrison of the University of Adelaide in Australia. The burrow and trapdoor provides the spiders with shelter and protection as well as a means for capturing prey. And it means that the spiders don’t really need to travel farther than a few meters over the course of a lifetime.

There was evidence, though, that the ancestors of these Australian spiders might have traveled millions of meters to get to Australia — from Africa. That isn’t as odd as it might seem, since Australia used to be connected to other continents long ago in the supercontinent Gondwana. And humans have been known to transport species all over the planet. But there’s a third option, too: The spiders might have floated their way across an ocean.

To figure out which story is most likely true, Harrison and her colleagues looked at the spider’s genes. They turned to six genes that have been well-studied by spider biologists seeking to understand relationships between species. The researchers looked at those genes in seven M. rainbowi specimens from Kangaroo Island, five species of Moggridgea spiders from South Africa and seven species of southwestern Australia spiders from the closely related genus Bertmainius.

Using that data, the researchers built a spider family tree that showed which species were most closely related and how long ago their most recent common ancestor lived. M. rainbowi was most closely related to the African Moggridgea spiders, the analysis revealed. And the species split off some 2 million to 16 million years ago, Harrison and her colleagues report August 2 in PLOS ONE.

The timing of the divergence was long after Gondwana split up. And it was long before either the ancestors of Australia’s aboriginal people or later Europeans showed up on the Australian continent. While it may be improbable that a colony of spiders survived a journey of 10,000 kilometers across the Indian Ocean, that is the most likely explanation for how the trapdoor spiders got to Kangaroo Island, the researchers conclude.

Such an ocean journey would not be unprecedented for spiders in this genus, Harrison and her colleagues note. There are three species of Moggridgea spiders that are known to live on islands off the shore of the African continent. Two live on islands that were once part of the mainland, and they may have diverged at the same time that their islands separated from Africa. But the third, M. nesiota, lives on the Comoros, which are volcanic islands. The spiders must have traveled across 340 kilometers of ocean to get there.
These types of spiders may be well-suited to ocean travel. If a large swatch of land washes into the sea, laden with arachnids, the spiders may be able to hide out in their nests for the journey. Plus, they don’t need a lot of food, can resist drowning and even “hold their breath” and survive on stored oxygen during periods of temporary flooding, the researchers note.

We’re going through a comic book phase at my house. Since lucking into the comics stash at the library, my 4-year-old refuses any other literary offering. Try as I might to rekindle her love of Rosie Revere, my daughter shuns that scrappy little engineer for Superman every single night.

I know that comic fans abound, but I’ll admit that I get a little lost reading the books. The multi-paneled illustrations, the jumpy story lines and the fact that my daughter skips way ahead make it hard for me to engage. And I imagine that for a preliterate preschooler, that confusion is worse.

There’s evidence to this idea (although it won’t help me force my daughter to choose girl-power science lit over Superman). A recent study found that kids better learn new vocabulary from books when there’s just one picture to see at a time.

Psychologist Jessica Horst and colleague Zoe Flack, both of the University of Sussex in England, read stories to 36 3½-year-olds. These were specially designed storybooks, with pages as big as printer paper. And sprinkled into the text and reflected in the illustrations were a few nonsense words: An inverted, orange and yellow slingshot that mixed things, called a tannin, and a metal wheel used like a rolling pin, called a sprock.

The researchers wanted to know under which reading conditions kids would best pick up the meaning of the nonsense words. In some tests, a researcher read the storybook that showed two distinct pictures at a time. In other tests, only one picture was shown at a time. Later, the kids were asked to point to the “sprock,” which was shown in a separate booklet among other unfamiliar objects.

Kids who saw just one picture at a time were more likely to point to the sprock when they saw it again, the researchers found. The results, published June 30 in Infant and Child Development, show how important pictures can be for preliterate kids, says Horst.

“As parents, it’s easy to forget that children do not look at the written text until they themselves are learning to read,” she says. (This study shows how infrequently preschoolers look at the words.) That means that kids might focus on pictures that aren’t relevant to the words they’re hearing, a mismatch that makes it harder for them to absorb new vocabulary.
Does this mean parents ought to trash all books with multiple pictures on a page? Of course not. Horst and Flack found that for such books, gesturing toward the relevant picture got the word-learning rate back up. That means that parents ought to point at Wonder Woman’s Lasso of Truth or wave at the poor varlet that Shrek steals a lunch from. (Shrek!, the book by William Steig, contains delightful vocabulary lessons for children and adults alike.)

Those simple gestures, Horst says, will help you and your child “literally be on the same page.”

If you could put Uranus’ moon Cressida in a gigantic tub of water, it would float.

Cressida is one of at least 27 moons that circle Uranus. Robert Chancia of the University of Idaho in Moscow and colleagues calculated Cressida’s density and mass using variations in an inner ring of the planet as Uranus passed in front of a distant star. The team found that the density of the moon is 0.86 grams per cubic centimeter and its mass is 2.5×1017 kilograms. The results, reported August 28 on arXiv.org, are the first to reveal details about the moon. Knowing its density and mass helps researchers determine if and when Cressida might collide with another of Uranus’ moons and what will become of both of them.

Voyager 2 discovered Cressida and several other moons when the spacecraft flew by Uranus in 1986. Those moons, and two discovered later, orbit within 20,000 kilometers of Uranus and are the most tightly packed in the solar system.

Such close quarters puts the moons on collision courses. Based on the newly calculated mass and density of Cressida, simulations suggest it will slam into another moon, Desdemona, in a million years.

Cressida’s density suggests it is made of water ice with some contamination by a dark material. If the other moons have similar compositions, the moon collisions may happen in the more distant future than researchers thought. Determining what the moons are made of will also reveal their ultimate fate after a collision: whether they merge, bounce off each other or shatter into millions of pieces.

When you think about it, it shouldn’t be surprising that there’s more than one way to explain quantum mechanics. Quantum math is notorious for incorporating multiple possibilities for the outcomes of measurements. So you shouldn’t expect physicists to stick to only one explanation for what that math means. And in fact, sometimes it seems like researchers have proposed more “interpretations” of this math than Katy Perry has followers on Twitter.

So it would seem that the world needs more quantum interpretations like it needs more Category 5 hurricanes. But until some single interpretation comes along that makes everybody happy (and that’s about as likely as the Cleveland Browns winning the Super Bowl), yet more interpretations will emerge. One of the latest appeared recently (September 13) online at arXiv.org, the site where physicists send their papers to ripen before actual publication. You might say papers on the arXiv are like “potential publications,” which someday might become “actual” if a journal prints them.

And that, in a nutshell, is pretty much the same as the logic underlying the new interpretation of quantum physics. In the new paper, three scientists argue that including “potential” things on the list of “real” things can avoid the counterintuitive conundrums that quantum physics poses. It is perhaps less of a full-blown interpretation than a new philosophical framework for contemplating those quantum mysteries. At its root, the new idea holds that the common conception of “reality” is too limited. By expanding the definition of reality, the quantum’s mysteries disappear. In particular, “real” should not be restricted to “actual” objects or events in spacetime. Reality ought also be assigned to certain possibilities, or “potential” realities, that have not yet become “actual.” These potential realities do not exist in spacetime, but nevertheless are “ontological” — that is, real components of existence.

“This new ontological picture requires that we expand our concept of ‘what is real’ to include an extraspatiotemporal domain of quantum possibility,” write Ruth Kastner, Stuart Kauffman and Michael Epperson.

Considering potential things to be real is not exactly a new idea, as it was a central aspect of the philosophy of Aristotle, 24 centuries ago. An acorn has the potential to become a tree; a tree has the potential to become a wooden table. Even applying this idea to quantum physics isn’t new. Werner Heisenberg, the quantum pioneer famous for his uncertainty principle, considered his quantum math to describe potential outcomes of measurements of which one would become the actual result. The quantum concept of a “probability wave,” describing the likelihood of different possible outcomes of a measurement, was a quantitative version of Aristotle’s potential, Heisenberg wrote in his well-known 1958 book Physics and Philosophy. “It introduced something standing in the middle between the idea of an event and the actual event, a strange kind of physical reality just in the middle between possibility and reality.”

In their paper, titled “Taking Heisenberg’s Potentia Seriously,” Kastner and colleagues elaborate on this idea, drawing a parallel to the philosophy of René Descartes. Descartes, in the 17th century, proposed a strict division between material and mental “substance.” Material stuff (res extensa, or extended things) existed entirely independently of mental reality (res cogitans, things that think) except in the brain’s pineal gland. There res cogitans could influence the body. Modern science has, of course, rejected res cogitans: The material world is all that reality requires. Mental activity is the outcome of material processes, such as electrical impulses and biochemical interactions.

Kastner and colleagues also reject Descartes’ res cogitans. But they think reality should not be restricted to res extensa; rather it should be complemented by “res potentia” — in particular, quantum res potentia, not just any old list of possibilities. Quantum potentia can be quantitatively defined; a quantum measurement will, with certainty, always produce one of the possibilities it describes. In the large-scale world, all sorts of possibilities can be imagined (Browns win Super Bowl, Indians win 22 straight games) which may or may not ever come to pass.

If quantum potentia are in some sense real, Kastner and colleagues say, then the mysterious weirdness of quantum mechanics becomes instantly explicable. You just have to realize that changes in actual things reset the list of potential things.

Consider for instance that you and I agree to meet for lunch next Tuesday at the Mad Hatter restaurant (Kastner and colleagues use the example of a coffee shop, but I don’t like coffee). But then on Monday, a tornado blasts the Mad Hatter to Wonderland. Meeting there is no longer on the list of res potentia; it’s no longer possible for lunch there to become an actuality. In other words, even though an actuality can’t alter a distant actuality, it can change distant potential. We could have been a thousand miles away, yet the tornado changed our possibilities for places to eat.

It’s an example of how the list of potentia can change without the spooky action at a distance that Einstein alleged about quantum entanglement. Measurements on entangled particles, such as two photons, seem baffling. You can set up an experiment so that before a measurement is made, either photon could be spinning clockwise or counterclockwise. Once one is measured, though (and found to be, say, clockwise), you know the other will have the opposite spin (counterclockwise), no matter how far away it is. But no secret signal is (or could possibly be) sent from one photon to the other after the first measurement. It’s simply the case that counterclockwise is no longer on the list of res potentia for the second photon. An “actuality” (the first measurement) changes the list of potentia that still exist in the universe. Potentia encompass the list of things that may become actual; what becomes actual then changes what’s on the list of potentia.

Similar arguments apply to other quantum mysteries. Observations of a “pure” quantum state, containing many possibilities, turns one of those possibilities into an actual one. And the new actual event constrains the list of future possibilities, without any need for physical causation. “We simply allow that actual events can instantaneously and acausally affect what is next possible … which, in turn, influences what can next become actual, and so on,” Kastner and colleagues write.

Measurement, they say, is simply a real physical process that transforms quantum potentia into elements of res extensa — actual, real stuff in the ordinary sense. Space and time, or spacetime, is something that “emerges from a quantum substratum,” as actual stuff crystalizes out “of a more fluid domain of possibles.” Spacetime, therefore, is not all there is to reality.

It’s unlikely that physicists everywhere will instantly cease debating quantum mysteries and start driving cars with “res potentia!” bumper stickers. But whether this new proposal triumphs in the quantum debates or not, it raises a key point in the scientific quest to understand reality. Reality is not necessarily what humans think it is or would like it to be. Many quantum interpretations have been motivated by a desire to return to Newtonian determinism, for instance, where cause and effect is mechanical and predictable, like a clock’s tick preceding each tock.

But the universe is not required to conform to Newtonian nostalgia. And more generally, scientists often presume that the phenomena nature offers to human senses reflect all there is to reality. “It is difficult for us to imagine or conceptualize any other categories of reality beyond the level of actual — i.e., what is immediately available to us in perceptual terms,” Kastner and colleagues note. Yet quantum physics hints at a deeper foundation underlying the reality of phenomena — in other words, that “ontology” encompasses more than just events and objects in spacetime.
This proposition sounds a little bit like advocating for the existence of ghosts. But it is actually more of an acknowledgment that things may seem ghostlike only because reality has been improperly conceived in the first place. Kastner and colleagues point out that the motions of the planets in the sky baffled ancient philosophers because supposedly in the heavens, reality permitted only uniform circular motion (accomplished by attachment to huge crystalline spheres). Expanding the boundaries of reality allowed those motions to be explained naturally.

Similarly, restricting reality to events in spacetime may turn out to be like restricting the heavens to rotating spheres. Spacetime itself, many physicists are convinced, is not a primary element of reality but a structure that emerges from processes more fundamental. Because these processes appear to be quantum in nature, it makes sense to suspect that something more than just spacetime events has a role to play in explaining quantum physics.

True, it’s hard to imagine the “reality” of something that doesn’t exist “actually” as an object or event in spacetime. But Kastner and colleagues cite the warning issued by the late philosopher Ernan McMullin, who pointed out that “imaginability must not be made the test for ontology.” Science attempts to discover the real world’s structures; it’s unwarranted, McMullin said, to require that those structures be “imaginable in the categories” known from large-scale ordinary experience. Sometimes things not imaginable do, after all, turn out to be real. No fan of the team ever imagined the Indians would win 22 games in a row.

A newly fabricated material does more than just hold up under pressure. Unlike many ordinary objects that shrink when squeezed, the metamaterial — a synthetic structure designed to exhibit properties not typically found in natural materials — expands at higher pressures.

This counterintuitive material is made up of a grid of hollow 3-D crosses — shaped like six-way pipe fittings — mere micrometers across. When surrounding pressure of air, water or some other substance increases, the crosses’ circular surfaces bow inward. Because of the way these crosses are connected with levers, that warping forces the crosses to rotate and push away from each other, causing the whole structure to expand, says study coauthor Jingyuan Qu, a physicist at Karlsruhe Institute of Technology in Germany.
The researchers were “very clever about how they connected this quite complex set of structural elements,” says Michael Haberman, a mechanical engineer at the University of Texas at Austin, who wasn’t involved in the work.

Qu and colleagues fashioned a microcube of their metamaterial, described in a paper accepted to Physical Review X, from a plasticlike substance, using a microversion of 3-D printing. When the researchers placed the material inside a gas chamber and cranked up the air pressure from one bar (about the atmospheric pressure at sea level) to five bars, the cube’s volume increased by about 3 percent.
Until now, researchers have only described such pressure-expanding metamaterials in mathematical models or computer simulations, says Joseph Grima, a materials scientist at the University of Malta in Msida not involved in the work. The new metamaterial provides “much-needed proof” that this type of stuff can actually be fabricated, he says.

Adjusting the thickness of the crosses’ surfaces could make this new metamaterial more or less expandable: The thicker it is, the less the structure expands. A metamaterial fine-tuned to stay the same size under a wide range of pressures could be used to build equipment that withstands the crushing pressures of the deep sea or the vacuum of outer space.

When you lock eyes with a baby, it’s hard to look away. For one thing, babies are fun to look at. They’re so tiny and cute and interesting. For another, babies love to stare back. I remember my babies staring at me so hard, with their eyebrows raised and unblinking eyes wide open. They would have killed in a staring contest.

This mutual adoration of staring may be for a good reason. When a baby and an adult make eye contact, their brain waves fall in sync, too, a new study finds. And those shared patterns of brain activity may actually pave the way for better communication between baby and adult: Babies make more sweet, little sounds when their eyes are locked onto an adult who is looking back. The scientists report the results online November 28 in the Proceedings of the National Academy of Sciences.

Psychologist Victoria Leong of the University of Cambridge and Nanyang Technological University in Singapore and colleagues invited infants into the lab for two experiments. In the first, the team outfitted 17 8-month-old babies with EEG caps, headwear covered with electrodes that measure the collective behavior of nerve cells across the brain. The infants watched a video in which an experimenter, also outfitted in an EEG cap, sung a nursery rhyme while looking either straight ahead at the baby, at the baby but with her head turned at a 20-degree angle, or away from the baby and with her head turned at a 20-degree angle.
When the researcher looked at the baby (either facing the baby or with her head slightly turned), the babies’ brains responded, showing activity patterns that started to closely resemble those of the researcher.

The second experiment moved the test into real life. The same researcher from the video sat near 19 different babies. Again, both the babies and the researcher wore EEG caps to record their brain activity. The real-life eye contact prompted brain patterns similar to those seen in the video experiment: When eyes met, brain activity fell in sync; when eyes wandered, brain activity didn’t match as closely.

The baby’s and the adult’s brain activity appeared to get in sync by meeting in the middle. When gazes were shared, a baby’s brain waves became more like the researcher’s, and the researcher’s more like the baby’s. That finding is “giving new insights into infants’ amazing abilities to connect to, and tune in with, their adult caregivers,” Leong says.

What are simpatico brain waves actually good for, you might ask? Well, researchers don’t know exactly, but they have some ideas. When high school students’ brain waves were in sync with one another, the kids reported being more engaged in the classroom, a recent study found. And when two adults reach a mutual understanding, their brains synchronize, too, says another study. These findings hint that such synchronization lets signals flow easily between two brains, though Leong says that much more research needs to be done before scientists understand synchronization’s relevance to babies’ communication and learning.
That easy signal sending is something that happened between the babies and the adult, too. When the experimenter was looking at the babies, the babies made more vocalizations. And in turn, these sweet sounds seemed to have made the experimenter’s brain waves even more similar to those of the babies.

It’s a beautiful cycle, it seems, when eyes and brains meet. And that meeting spot is probably where some interesting learning happens, for both adult and baby.

NEW ORLEANS — Jupiter’s Great Red Spot has deep roots. Data from the first pass of NASA’s Juno spacecraft over the incessant storm show that its clouds stretch at least 350 kilometers down into the planet’s atmosphere. That means the storm is about as deep as the International Space Station is high above the Earth.

Juno has been orbiting Jupiter since July 4, 2016, and it made its first close flyby of the red spot about a year later (SN Online: 7/7/17). As the spacecraft swooped 9,000 kilometers above the giant storm, Juno’s microwave radiometer peered through the deep layers of cloud, measuring the atmosphere’s temperature down hundreds of kilometers.
“Juno is probing beneath these clouds, and finding the roots of the red spot,” Juno co-investigator Andrew Ingersoll of Caltech said December 11 at a news conference at the American Geophysical Union’s fall meeting. Cheng Li of Caltech presented the research at AGU on December 12.
The radiometer probes different layers of the atmosphere by measuring the gas in six different microwave wavelengths. Ingersoll and his colleagues found that the gas beneath the red spot’s surface gets warmer with depth, and a warm zone at the same location as the spot was visible down to 350 kilometers
The fact that the 16,000-kilometer-wide spot is warmer at the bottom than at the top could help explain the storm’s screaming wind speeds of about 120 meters per second. Warm air rises, so the internal heat could provide energy to churn the storm.

Juno principal investigator Scott Bolton of the Southwest Research Institute in San Antonio notes that the spot “goes as deep as we can see,” but it could go deeper. “I’m not sure we’ve established the true foot,” he says. On a future flyby, Juno will try to use gravity data to detect the storm at depths of thousands of kilometers. If the spot does go down that deep, theorists will struggle to explain why, Bolton says.

The only previous data on Jupiter’s interior came from the Galileo spacecraft, which ended its mission by entering Jupiter’s atmosphere at a single point in 1995. “I like to say that if aliens sent a probe to Earth and it landed in the Sahara, they would conclude the Earth is all desert,” says planetary scientist Michael Wong of Caltech, who was not involved in the new study. “Juno getting this global view gives us a new understanding of the inner workings … We have never really seen the interior of a giant planet in this way before.”

NEW ORLEANS — For the first time, scientists have definitively linked human-caused climate change to extreme weather events.

A handful of extreme events that occurred in 2016 — including a deadly heat wave that swept across Asia — simply could not have happened due to natural climate variability alone, three new studies find. The studies were part of a special issue of the Bulletin of the American Meteorological Society, also known as BAMS, released December 13.
These findings are a game changer — or should at least be a conversation changer, Jeff Rosenfeld, editor in chief of BAMS, said at a news conference that coincided with the studies’ release at the American Geophysical Union’s annual meeting. “We can no longer be shy about talking about the connection between human causes of climate change and weather,” he said.

For the last six years, BAMS has published a December issue containing research on extreme weather events from the previous year that seeks to disentangle the role of anthropogenic climate change from natural variability. The goal from the start has been to find ways to improve the science of such attribution, said Stephanie Herring of the National Oceanic and Atmospheric Administration’s National Centers for Environmental Information in Boulder, Colo., who was lead editor of the latest issue.

To date, BAMS has published 137 attribution studies. But this is the first time that any study has found that a weather event was so extreme that it was outside the bounds of natural variability — let alone three such events, Herring said.

Story continues below map
In addition to the Asia heat wave, those events were the record global heat in 2016 and the growth and persistence of a large swath of high ocean temperatures, nicknamed “the Blob,” in the Bering Sea off the coast of Alaska. The unusually warm waters, which lingered for about a year and a half, have been linked to mass die-offs of birds, collapsed codfish populations in the Gulf of Alaska and altered weather patterns that brought drought to California.

Many of the other 24 studies in the new issue found a strong likelihood of human influence on extreme weather events, but stopped short of saying they were completely out of the realm of natural variability. One study found that an already strong El Niño in 2016 was probably enhanced by human influence, contributing to drought and famine conditions in southern Africa. Another reported that greenhouse gas–driven warming of sea surface temperatures in the Coral Sea was the main factor driving an increase in coral bleaching risk along the Great Barrier Reef. But not all of the studies linked 2016’s extreme events to human activity. Record-breaking rainfall in southeastern Australia between July and September, for example, was due to natural variability, one study found.

With hurricanes, wildfires and drought, 2017 is chock-full of extreme event candidates for next year’s crop of BAMS attribution studies. Already, the likelihood of human influence on the extreme rainfall from Hurricane Harvey is the subject of three independent studies, two of which were also presented at the American Geophysical Union meeting. The storm dropped about 1.3 meters of water on Houston and its surrounding areas in August. The three studies, discussed in a separate news conference December 13, found that human influence probably increased the hurricane’s total rainfall, by anywhere from at least 15 percent to at least 19 percent.

Story continues below image
“I think [the BAMS studies] speak to the profound nature of the impacts we’re now seeing,” says Michael Mann, a climate scientist at Penn State who was not involved in any of the studies. But Mann says he’s concerned that many researchers are too focused on quantifying how much human influence was responsible for a particular event, rather than how human influence affects various processes on the planet. One example, he notes, is the established link between rising temperatures and increased moisture in the atmosphere that is also implicated in Hurricane Harvey’s extreme rainfall.

Another possible issue with attribution science, he says, is that the current generation of simulations simply may not be capable of capturing some of the subtle changes in the climate and oceans — a particular danger when it comes to studies that find no link to human activities. It’s a point that climate scientist Andrew King of the University of Melbourne in Australia, who authored the paper on Australia’s rainfall, also noted at the news conference.

“When we find no clear signal for climate change, there might not have been a human influence on the event, or [it might be that] the particular factors of the event that were investigated were not influenced by climate change,” he said. “It’s also possible that the given tools we have today can’t find this climate change signal.”

Rosenfeld noted that people tend to talk about the long odds of an extreme weather event happening. But with studies now saying that climate change was a necessary condition for some extreme events, discussions about long odds no longer apply, he said. “These are new weather extremes made possible by a new climate.”

The neutron star collision heard and seen around the world has failed to fade. That lingering glow could mean that a jet of bright matter created in the crash has diffused into a glowing, billowy cocoon that surrounds the merged star, researchers report online December 20 in Nature.

Gravitational waves from the collision between two ultradense stellar corpses was picked up in August by the Advanced Laser Interferometer Gravitational-Wave Observatory, LIGO, and its sister experiment in Italy, Advanced Virgo (SN: 11/11/17, p. 6). Using telescopes on the ground and in space, physicists raced to conduct follow-up observations, and found that the collision released light across the electromagnetic spectrum.
Right away, the event looked unusual, says astrophysicist Kunal Mooley, who conducted the research while at the University of Oxford. Physicists think that a jet of fast-moving, bright material blasts out of the center of neutron star collisions. If that jet is aimed directly at Earth, telescopes can see it as an ephemeral flash of light called a short gamma-ray burst, or GRB.
But the gamma-ray signals produced by the August collision were 10,000 times less bright than those seen in other detected short gamma-ray bursts. Even stranger, X-rays and radio waves from the event didn’t appear until about 16 days after the collision. Most short gamma-ray bursts are visible in X-rays and radio waves right away and fade over time.
Astronomers thought those oddities meant the jet was facing slightly away from Earth and expected the light to fade quickly. But Mooley and colleagues continued tracking the glow with three radio telescope arrays on three continents for more than 100 days after the collision. Radio wave emissions continued to brighten for at least 93 days, and are still visible now, the team found. (X-rays were temporarily blocked when the neutron star moved behind the sun from Earth’s perspective.)

“This thing continues to rise, instead of fading into oblivion as we expected,” says astrophysicist Wen-fai Fong of Northwestern University in Evanston, Ill., who was not involved in the new study.

The finding may mean that astronomers are seeing a new kind of gamma-ray burst. Mooley and colleagues suggest that the rise in radio wave emissions could be explained if the jet slammed into a shell of neutron-rich material kicked out in the neutron star crash, transferring most of its energy to that debris and smothering the jet. That extra energy could create a glowing cocoon that keeps radiating far longer than the original blast.

The new result is “really challenging our understanding of what physics is happening from this merger,” Fong says. But, she adds, “the jury is still out on whether this is the same as the short GRBs we’ve seen over the past decade, or whether it’s something completely different,” such as a luminescent cocoon. She and her colleagues also took radio wave observations of the merged stars in the first 100 days after the collision. The team is preparing a paper with a different interpretation that includes a jet emerging from the wreckage later, she says.

Other explanations for the lingering light are possible, Mooley acknowledges. Future detections “will give us an opportunity to really study … what fraction of neutron star mergers give rise to [short] GRBs and what fraction give rise to other phenomena and explosions that we haven’t seen so far in our universe,” he says.

2017 revealed some surprising biology of organisms large and small, from quick-dozing elephants to sex-changing lizards and carbon-dumping sea creatures.

Switch it up
Toasty temperatures trump genetics when it comes to the sex of a bearded dragon lizard. Now researchers have found how RNA editing helps turn overheated male embryos into females (SN Online: 6/14/17).

Homegrown
Giant larvaceans don’t have noses, but they sure know how to blow snot bubbles. The sea invertebrates live in disposable “mucus houses” that, based on recent observations, collect food fast. When these larvaceans ditch a dirty house and “sneeze” themselves a new one, they might send a lot of carbon to the deep sea (SN: 6/10/17, p. 13).

Blood and guts
Antarctic-dwelling sea spiders use their long legs for more than creepy-crawling below the ice. Stretches of digestive tract in the creatures’ legs do double duty — not only digesting meals, but also pumping an arthropod version of blood and oxygen through the rest of the body (SN: 2/4/17, p. 13).

Fluorescent fashion
South American polka dot tree frogs are the first amphibians known to naturally fluoresce. The frogs’ intense blue-green glow might play a role in complex courtship and fighting behaviors, biologists propose (SN: 4/15/17, p. 4).

Brainless beauty sleep
Upside-down jellyfish are the first brainless animals known to catch some z’s, lab experiments suggest (SN: 10/28/17, p. 10). The finding raises new questions about when and why sleep evolved.

Pachyderm power nap
For some wild elephants, a good night’s sleep ends soon after it starts. Electronic monitoring of two African elephants found that the animals snooze about two hours per day — the shortest sleep requirement recorded for mammals (SN: 4/1/17, p. 10).

Heads up
Chop off a hydra’s head, and two more grow in its place — or so the ancient Greek myth goes. By fiddling with the cytoskeletons of real-life hydras, researchers found that the pond polyps rely on mechanical forces as well as molecular cues to regenerate head and tentacles in the right places (SN: 3/4/17, p. 19).

Balancing act
Flamingos may be more stable standing on one leg than two, especially when asleep, researchers reported (SN: 6/24/17, p. 15). The blushing bird’s center of gravity is located near its tucked-in knee, which helps with stability. A one-legged stance requires little muscular effort, the scientists say, but others caution that it may not be an energy saver.

Ultimate survivor
Tardigrades are known for withstanding extreme temperatures, intense radiation and even the vacuum of space. Those adaptations could help this hardy lineage survive until Earth is engulfed by the sun in several billion years, researchers estimate (SN Online: 7/14/17). An analysis of the microscopic water bears’ genetic blueprints offers clues to their survival strategies, and challenges claims that tardigrades are extreme gene swappers (SN: 8/19/17, p. 13).

Paint it blue
Scientists borrowed a gene each from Canterbury bells and butterfly peas to breed the world’s first true blue chrysanthemums. The method could be used to give other flower species the blues (SN: 8/19/17, p. 12).