Wind turbines could offer a double whammy in the fight against climate change.
Besides harnessing wind to generate clean energy, turbines may help to funnel carbon dioxide to systems that pull the greenhouse gas out of the air (SN: 8/10/21). Researchers say their simulations show that wind turbines can drag dirty air from above a city or a smokestack into the turbines’ wakes. That boosts the amount of CO2 that makes it to machines that can remove it from the atmosphere. The researchers plan to describe their simulations and a wind tunnel test of a scaled-down system at a meeting of the American Physical Society’s Division of Fluid Dynamics in Indianapolis on November 21. Addressing climate change will require dramatic reductions in the amount of carbon dioxide that humans put into the air — but that alone won’t be enough (SN: 3/10/22). One part of the solution could be direct air capture systems that remove some CO2 from the atmosphere (SN: 9/9/22).
But the large amounts of CO2 produced by factories, power plants and cities are often concentrated at heights that put it out of reach of machinery on the ground that can remove it. “We’re looking into the fluid dynamics benefits of utilizing the wake of the wind turbine to redirect higher concentrations” down to carbon capture systems, says mechanical engineer Clarice Nelson of Purdue University in West Lafayette, Ind.
As large, power-generating wind turbines rotate, they cause turbulence that pulls air down into the wakes behind them, says mechanical engineer Luciano Castillo, also of Purdue. It’s an effect that can concentrate carbon dioxide enough to make capture feasible, particularly near large cities like Chicago.
“The beauty is that [around Chicago], you have one of the best wind resources in the region, so you can use the wind turbine to take some of the dirty air in the city and capture it,” Castillo says. Wind turbines don’t require the cooling that nuclear and fossil fuel plants need. “So not only are you producing clean energy,” he says, “you are not using water.”
Running the capture systems from energy produced by the wind turbines can also address the financial burden that often goes along with removing CO2 from the air. “Even with tax credits and potentially selling the CO2, there’s a huge gap between the value that you can get from capturing it and the actual cost” that comes with powering capture with energy that comes from other sources, Nelson says. “Our method would be a no-cost added benefit” to wind turbine farms.
There are probably lots of factors that will impact CO2 transport by real-world turbines, including the interactions the turbine wakes have with water, plants and the ground, says Nicholas Hamilton, a mechanical engineer at the National Renewable Energy Laboratory in Golden, Colo., who was not involved with the new studies. “I’m interested to see how this group scaled their experiment for wind tunnel investigation.”
You might feel a spark when you talk to your crush, but living things don’t require romance to make electricity. A study published October 24 in iScience suggests that the electricity naturally produced by swarming insects like honeybees and locusts is an unappreciated contributor to the overall electric charge of the atmosphere.
“Particles in the atmosphere easily charge up,” says Joseph Dwyer, a physicist at the University of New Hampshire in Durham who was not involved with the study. “Insects are little particles moving around the atmosphere.” Despite this, the potential that insect-induced static electricity plays a role in the atmosphere’s electric field, which influences how water droplets form, dust particles move and lightning strikes brew, hasn’t been considered before, he says. Scientists have known about the minuscule electric charge carried by living things, such as insects, for a long time. However, the idea that an electric bug-aloo could alter the charge in the air on a large scale came to researchers through sheer chance.
“We were actually interested in understanding how atmospheric electricity influences biology,” says Ellard Hunting, a biologist at the University of Bristol in England. But when a swarm of honeybees passed over a sensor meant to pick up background atmospheric electricity at the team’s field station, the scientists began to suspect that the influence could flow the other way too.
Hunting and colleagues, including biologists and physicists, measured the change in the strength of electric charge when other honeybee swarms passed over the sensor, revealing an average voltage increase of 100 volts per meter. The denser the insect swarm, the greater the charge produced.
This inspired the team to think about even larger insect swarms, like the biblical hordes of locusts that plagued Egypt in antiquity (and, in 2021, Las Vegas (SN: 3/30/21)). Flying objects, from animals to airplanes, build up static electricity as they move through the air. The team measured the charges of individual desert locusts (Schistocerca gregaria) as they flew in a wind tunnel powered by a computer fan. Taking data on locust density from other studies, the team then used a computer simulation based on the honeybee swarm data to scale up these single locust measurements into electric charge estimates for an entire locust swarm. Clouds of locusts could produce electricity on a per-meter basis on par with that in storm clouds, the scientists report.
Hunting says the results highlight the need to explore the unknown lives of airborne animals, which can sometimes reach much greater heights than honeybees or locusts. Spiders, for example, can soar kilometers above Earth when “ballooning” on silk threads to reach new habitats (SN: 7/5/18). “There’s a lot of biology in the sky,” he says, from insects and birds to microorganisms. “Everything adds up.”
Though some insect swarms can be immense, Dwyer says that electrically charged flying animals are unlikely to ever reach the density required to produce lightning like storm clouds do. But their presence could interfere with our efforts to watch for looming strikes that could hurt people or damage property.
“If you have something messing up our electric field measurements, that could cause a false alarm,” he says, “or it could make you miss something that’s actually important.” While the full effect that insects and other animals have on atmospheric electricity remains to be deduced, Dwyer says these results are “an interesting first look” into the phenomenon.
Hunting says this initial step into an exciting new area of research shows that working with scientists from different fields can spark shocking findings. “Being really interdisciplinary,” he says, “allows for these kinds of serendipitous moments.”
A new video offers the first evidence that these nocturnal lemurs of Madagascar stick their fingers up their noses and lick off the mucus. They don’t use just any finger for the job, either. The primates go spelunking for snot with the ultralong, witchy middle finger they typically use to find and fish grubs out of tree bark.
A reconstruction of the inside of an aye-aye’s head based on CT scans shows that this spindly digit probably pokes all the way through the animal’s nasal passages to reach its throat, researchers report online October 26 in the Journal of Zoology. “This is a brilliant example of how science can serve human curiosity,” says Michael Haslam, a primate archaeologist based in London who was not involved in the new work. “My first take was that it’s a cool — and a bit creepy — video, but [the researchers] have gone beyond that initial reaction of ‘What on Earth?’ to actually explore what’s happening inside the animal.”
The new footage stars Kali, a female aye-aye (Daubentonia madagascariensis) at the Duke Lemur Center in Durham, N.C. “The aye-aye stopped eating and started to pick its nose, and I was really surprised,” says evolutionary biologist Anne-Claire Fabre, who filmed the video. “I was wondering where the finger was going.” An aye-aye is about as big as a house cat, but its clawed middle finger is some 8 centimeters long. And Kali was plunging almost the entire digit up her snout to sample her own snot with dainty licks.
“There is one moment where the camera is [shaking], and I was giggling,” says Fabre, of the Natural History Museum of Bern in Switzerland. Afterward, she asked her colleagues if they had ever seen an aye-aye picking its nose. “The ones that were working a lot with aye-ayes would tell me, ‘Oh, yeah, it’s happening really often,’” says Fabre, who later witnessed the behavior in several other aye-ayes. This got Fabre and her colleagues curious about how many other primate species have been caught with their fingers in their nostrils. The researchers scoured the literature for past studies and the internet for other videos documenting the behavior.
Unfortunately, “most of the literature that we were finding were jokes,” Fabre says. “I was really surprised, because there is a lot of literature on other types of pretty gross behaviors, such as coprophagy,” or poo eating, among animals (SN: 7/19/21). But between all the bogus articles, the team did find some real reports of primate nose picking, including research done by Jane Goodall in the 1970s.
Aye-ayes are now the 12th known species of primate, including humans, to pick their noses and snack on the snot, the researchers found. Others include gorillas, chimpanzees, bonobos, orangutans and macaques. Nose pickers tend to be primates that have especially good dexterity and use tools.
“The team [has] given us the first map of nose picking across our primate family tree, which immediately raises questions about just how much of this behavior is happening out there, unseen or unreported,” Haslam says. He remembers once seeing a capuchin monkey using a twig or stem to pick its nose (SN: 9/6/15).
“I’m surprised that there aren’t more reports on nose picking, especially from zoos where animals are watched every day,” Haslam adds. “Perhaps our own social stigma around it means that scientists are less likely to want to report nose-picking animals, or it may even be seen as too common to be interesting.” The fact that so many primate species have been spotted picking their noses and eating the boogers makes Fabre’s team and Haslam wonder whether this seemingly nasty habit has some unknown advantage. Perhaps eating germ-laden boogers boosts the immune system.
For now, untangling the evolutionary origins and potential perks of nose picking will require a more complete census of what species — primate or otherwise — mine and munch on their own mucus.
Since Russia’s invasion of Ukraine in late February, people around the world have watched the war play out in jarring detail — at least, in countries with open access to social media platforms such as Twitter, Facebook, TikTok and the messaging app Telegram.
“The way that social media has brought the war into the living rooms of people is quite astounding,” says Joan Donovan, the research director of the Shorenstein Center on Media, Politics and Public Policy at Harvard University. Fighting and explosions play out nearly in real time, and video messages from embattled Ukrainian president Volodymyr Zelenskyy have stirred support across the West.
But that’s not all. Social media is actually changing the way wars are fought today, says political scientist Thomas Zeitzoff of American University in Washington, D.C., who is an expert on political violence. The platforms have become important places to recruit fighters, organize action, spread news and propaganda and — for social scientists — to gather data on conflicts as they unfold.
As social platforms have become more powerful, governments and politicians have stepped up efforts to use them — or ban them, as in Russia’s recent blocking of Facebook, Twitter and Instagram. And in a first, the White House held a special briefing on the Ukraine war with TikTok stars such as 18-year-old Ellie Zeiler, who has more than 10 million followers. The administration hopes to shape the messages of young influencers who are already important sources of news and information for their audiences.
The Ukraine war is shining a spotlight on social media’s role as a political tool, says Donovan, whose Technology and Social Change Project team has been following the spread of disinformation in the conflict. “This is a huge moment in internet history where we’re starting to see the power of these tech companies play out against the power of the state.” And that, she says, “is actually going to change the internet forever.”
Science News interviewed Donovan and Zeitzoff about social media’s influence on the conflict and vice versa. The following conversations have been edited for length and clarity.
SN: When did social media start to play a role in conflicts?
Zeitzoff: Some people would say the Zapatista uprising in Mexico, way back in the 1990s, because the Zapatistas used the internet [to spread their political message]. But I think the failed Green Revolution in Iran in 2007 and 2008 was one of the first, and especially the Arab Spring in the early 2010s. There was this idea that social media would be a “liberation technology” that allows people to hold truth to power.
But as the Arab Spring gave way to the Arab Winter [and its resurgence of authoritarianism], people started challenging that notion. Yes, it makes it easy to get a bunch of people out on the street [to protest], but it also makes it easier for governments to track these folks. SN: How do you see social media being used in the Ukrainian conflict, and what’s different now? Donovan: Some of the platforms that are more well-known, like Facebook and Twitter, are not as consequential as newer platforms like Telegram and TikTok. For instance, Ukrainian groups on Facebook started to build other channels for communication right before the Russian invasion because they felt that Facebook might get compromised. So Telegram has been a very important space for getting information and sharing news.
Telegram has also become a hot zone for propaganda and misinformation, where newer tactics are emerging such as fake debunked videos. These are videos that look like they’re news debunks showing that Ukraine is participating in media manipulation efforts, but they’re actually manufactured by Russia to make Ukraine look bad.
Zeitzoff: I think social media has probably afforded the Ukrainians an easier ability to communicate to their diaspora communities, whether in Canada, the United States or across Europe. It’s also increasingly affording unprecedented battlefield views.
But I think the bigger thing is to think about what these new suites of technology allow, like Volodymyr Zelenskyy holding live videos that basically allow him to show proof of life, and also put pressure on European leaders.
SN: Despite Russia’s big investments in disinformation, is Ukraine winning the social media war?
Zeitzoff: Up to the beginning of the conflict, many Ukrainians were skeptical of Zelenskyy’s ability to lead. But you look back at his presidential campaign, and he was doing Facebook videos where he would talk into the camera, in a very sort of intimate style of campaigning. So he knew how to use social media beforehand. And I think that has allowed Ukraine to communicate to Western audiences, basically, ‘give me money, give me weapons,’ and that has helped. There is an alternative scenario where perhaps if Russia’s military were slightly better organized and had a better social media campaign, it would become very difficult for Ukraine to hold.
And I would say that Russia’s propaganda has been sloppier. It’s not as good of a story. Ukraine already has the underdog sympathy, and they’ve been very good at capitalizing on it. They show their battlefield successes and highlight atrocities committed by Russians.
And the other thing is that social media has helped to organize foreign fighters and folks who have volunteered to go to Ukraine.
SN: Social media is also an enormous source of misinformation and disinformation. How is that playing out?
Donovan: We’re seeing recontextualized media [on TikTok and elsewhere], which is the reuse of content in a new context. And it usually also misrepresents the time and place of the content.
For instance, we’ve seen repurposed video game footage as if it was the war in Ukraine. While we [in the United States] don’t need real-time information to understand what’s happening in Ukraine, we do need access to the truth. Recontextualized media gets in the way of our right to truth.
And we want to make sure the information getting to people in Ukraine is as true and correct and vetted as possible, because they’re going to make a life-or-death decision that day about going out in search of food or trying to flee a certain area. So those people do need real-time accurate information.
There’s one other story about the way in which hope and morale can be decimated by disinformation. Among Ukrainians, there’s a lot of talk about when or if the United States or NATO will send planes. And there were these videos going around suggesting that the United States had already sent planes, and showing paratroopers jumping out. People were sharing these until they got to a reputable news source and heard the news that NATO was still not sending planes. So it can be something as innocent as a video that provides a massive amount of hope to people who share it, and then it’s all snatched away.
SN: What aren’t we seeing on social media?
Donovan: There’s a missing piece, which is that many social media algorithms are set to remove things that are torturous or gory. And so the very violent and vicious aftermath of war is something that the platforms are suppressing, just by virtue of their design.
So in order to get a complete picture of what has happened in Ukraine, people are going to have to see those videos [from other news sources] and be a global witness to the atrocity.
SN: Where is this all heading?
Zeitzoff: I think the biggest thing that’s changing is this decoupling of social media networks across great powers. So you have the Great Firewall [that censors the internet] in China, and I think Russia will be doing something very similar. And how does that influence the free flow of information?
Donovan: We try to understand how information warfare plays out as kind of a chess match between different actors. And what’s been incredible about the situation in Russia is you have this immense titan, the tech industry, pushing back on Russia by removing state media from their platforms. And then Russia counters by removing Facebook and Instagram in Russia.
This is the first time that we’ve seen these companies take action based on the request of other governments. In particular, Nick Clegg [the president of global affairs at Meta, the parent company of Facebook, Instagram and the messaging service WhatsApp] said that they were complying with Ukrainian asks. That means that they are taking some responsibility for the content that is being aired on their platforms. Whatever outcome happens over the next month, I don’t think the internet is going to be as global as it once was.
A few weeks ago, I was obsessed with my nose and throat. I was on a trip to Seattle to speak at a small, masks-required virology meeting about being a journalist during a pandemic. I went to graduate school there, so I was thrilled to see old friends and colleagues. But the irony that I was risking getting infected amid rising COVID-19 cases to get on a plane to talk with virologists about the pandemic didn’t escape me. I spent the whole week on high alert for the slightest hint of a sore throat or a runny nose. Despite masking, I worried that I’d get sick and be stuck thousands of miles from home or that I’d unknowingly pass the virus on to someone else.
Luckily, this story has a happy ending. I didn’t catch the coronavirus. None of my friends or former colleagues got sick. Although I didn’t escape completely unscathed; I did come down with a mystery, non-COVID cold that I suspect I caught from a friend’s baby. Still, the experience made me wonder — what if I didn’t have to worry so much about becoming a disease spreader because there were COVID-19 vaccines that helped my body control the virus in my nose? Researchers are working on vaccines that would hopefully do just that. You squirt these vaccines into your nostrils, rather than inject them into your arm muscle like the current COVID-19 shots. Sprayed up the nose, the vaccines teach our immune systems to fortify our nostrils against coronavirus, perhaps meaning we get less sick or making us less likely to transmit the virus to other people.
Jabs in the arm may not be as good at preventing transmission as nasal spray vaccines, some scientists suspect. The shots are better at building defenses that circulate in the blood or fluid that surrounds cells, which makes them great at protecting the lungs. And they have done what they are designed to do: curb severe disease and death (SN: 8/31/21). Booster doses help fend off severe COVID-19 better than the first two shots — especially for older people, studies show (SN: 4/29/22). But even with death rates down, that doesn’t mean our fight with coronavirus is over. Waning immune defenses combined with slippery versions of the coronavirus that can evade parts of our immune systems leave vaccinated people susceptible to infection. So we still need additional protection.
A panel of experts advising the U.S. Food and Drug Administration will meet later this month to weigh in on whether we might need a vaccine update for the fall. Updated shots may indeed be on the horizon: Preliminary data from vaccine developer Moderna show that its latest vaccine, which includes both omicron and the original virus, boosts the immune response against omicron as well as other variants such as delta, the company announced on June 8.
And on June 7 the FDA advisory committee recommended that the agency authorize a new COVID-19 vaccine for emergency use. This one, developed by the company Novavax, is based on a traditional method — showing the immune system purified viral proteins — which may be appealing to still unvaccinated people who are hesitant about the novel mRNA technology in Moderna’s and Pfizer’s shots (SN: 1/28/21). Other experts are working on vaccines that might hold up against an onslaught of variants, both present and future. And then, there are the nasal spray vaccines. They could not only protect our lungs, but also the mucous membranes that line the upper regions of our respiratory tracts such as the nose. Such sprays would give us not only a motion detector ready to sense an intruder in an inner room of a building but also an alarm system that goes off the second the front door opens.
That type of alarm system isn’t a brand-new tool. For example, there is a nasal influenza vaccine available in the United States called FluMist, which teaches the body to recognize four different strains. And there is a similar one in Europe called Fluenz Tetra. Each flu virus included in these vaccines is weakened but can replicate in the body. The attenuated viruses grow best at cooler temperatures found in our noses, not the warm environment of our lungs, a barrier that keeps them from making it to the lungs and causing influenza. But by taking off in the nose, replicating viruses kick off an immune response, so our bodies learn to set up reinforcements there.
Already roughly a dozen potential COVID-19 nasal vaccines have made it to clinical trials around the world. One developed by a company called Altimmune was abandoned after early results showed the vaccine didn’t prompt a good immune response in healthy participants. Others have shown promise when tested in animals.
The prospect of having nasal vaccines that may be able to curb transmission better than existing shots is understandably exciting. But these types of vaccines still have a way to go before hitting local pharmacies or doctors’ offices.
First, it’s crucial for the nasal vaccines to strike the right balance. Their sprays must be strong enough to provoke our immune systems, but still weak enough that there aren’t unwelcome symptoms or side effects. It’s also of course important to ensure the safety of vaccine candidates that include live, weakened viruses. Some nasal vaccine candidates are similar to the influenza vaccine and include live, weakened viruses. Most of these viruses aren’t the coronavirus itself, but rather harmless-to-human viruses that sport one coronavirus protein for our bodies to recognize. Others may not need a virus to grow in the body to work. One team is developing a nasal spray that includes only the coronavirus spike protein, which helps the virus break into cells. That spike spray could serve as a boost for people who received one of the mRNA vaccines, coaxing important immune cells to come live in the nose and other parts of the respiratory tract. Once there, those immune cells would be poised to kick into high gear if the coronavirus invades.
Second, nasal sprays face the same problem as current COVID-19 vaccines. What happens when the virus evolves in ways that help it hide from our immune system? We’ve already seen the consequences of that thanks to the delta and omicron waves that raced around the globe. And from 2016 to 2018, FluMist stumbled in the face of tweaked versions of some influenza viruses. Experts recommended that people get a different type of flu shot in those seasons. Just as researchers are considering updating existing COVID-19 shots to better mimic the viral variants currently wreaking havoc, nasal vaccines may also need regular updating.
If I had a choice, I would never catch coronavirus. But in the grand scheme of things, it’d be nice if a spray up my nose could drastically lower my chances of passing it on to someone else if I did get infected. If they make it to consumers, the nasal vaccines could make future COVID-19 waves much smaller than they are now. And after more than two years of navigating ever-larger waves, wouldn’t that be nice?
For the last two years, a person acting erratically in downtown Denver has likely first encountered unarmed health care workers rather than police. That shift stems from the rollout of a program known as Support Team Assisted Response, or STAR, which sends a mental health clinician and paramedic to respond to certain 911 calls about nonviolent behavior.
The program, and others like it, aim to defuse the tensions that can arise when police officers confront civilians in distress. Critics of these experimental programs have suggested that such reduced police involvement could allow crime to flourish. Now, researchers have found that during its pilot phase, the STAR program did not appear to lead to more violent crime. And reports of minor crimes substantially decreased, the researchers conclude June 8 in Science Advances. Much of that reduction occurred because the health responders do not issue citations or make arrests (SN: 12/18/21). But even that reduction in reported crime is beneficial, says economist Thomas Dee of Stanford University. “That person is getting health care instead of being arrested.”
Following the death of George Floyd at the hands of a white police officer and the subsequent rise of the Black Lives Matter movement in the summer of 2020, cities throughout the country have been rolling out programs like STAR. “We cannot police our way out of every social problem,” says Temitope Oriola, a sociologist at the University of Alberta in Edmonton, Canada. But so far there have been few studies of these programs’ effects on crime, let alone on the reduction of violence between police and the public (SN: 7/9/20).
Dee and Jayme Pyne, a sociologist also at Stanford, looked at the STAR program’s impact on crime reports. The duo investigated the program’s pilot phase, which ran from June to November 2020 and encompassed eight of the city’s 36 police precincts. Police officers and 911 operators in those eight precincts redirected calls for minor and non-dangerous complaints to STAR providers. These calls included concerns about trespassing, indecent exposure, intoxication and similar low-level offenses. During the six-month pilot, STAR providers responded to 748 calls, averaging roughly six incidents per eight-hour shift.
Dee and Pyne analyzed criminal offenses in all 36 precincts from December 2019 to November 2020. They then compared the change in crime rates in the eight precincts receiving STAR services with the change in crime rates in the other 28 precincts. The rate of violent crime remained unchanged across the board, including in the precincts where the STAR program was active, the researchers found. But there was a 34 percent drop in reports of minor offenses in the STAR precincts, from an average of about 84 offenses per month in each district to an average of about 56 citations.
The data also suggest that the actual level of minor crimes and complaints dropped too — that is, the drop wasn’t just due to a lack of reporting, the researchers say. Prior to the pilot, minor offenses in the eight precincts receiving STAR services resulted in an average of 1.4 citations per incident. So having health care workers rather than police respond to 748 such calls should generate roughly 1,000 fewer citations, the authors calculate. Instead, citations dropped by almost 1,400. Providing people in crisis with access to health services may be preventing them from reoffending, Dee says.
Research into these sorts of programs is crucial, says Michael Vermeer, a justice policy researcher with the RAND Corporation, a public policy research organization headquartered in Santa Monica, Calif. But he cautions against drawing firm conclusions from a single study launched at the onset of the COVID-19 crisis, which dramatically changed crime rates and patterns across the country. “They just got confounded by the pandemic,” Vermeer says.
Dee agrees that he and other researchers now need to replicate this study across more cities, and also scale up in Denver. The city has since expanded the STAR program beyond the initial pilot.
Even if researchers eventually find that STAR and similar programs don’t budge crime rates much, that doesn’t mean that the programs are unsuccessful, says sociologist Brenden Beck of the University of Colorado Denver. He points to the potential to save taxpayer dollars. Dee and Pyne estimate that a single offense processed through STAR costs about $150, compared with the roughly $600 it costs to process one through the criminal justice system.
What’s more, helping people having nonviolent mental health crises get help and stay out of jail lets these individuals hold onto their jobs and stay present in their family members’ lives, Beck says. “I would hope we as a research community move on to study the benefit of these programs not just in terms of crime but also in terms of human welfare.”
Astronomers have added a new species to the neutron star zoo, showcasing the wide diversity among the compact magnetic remains of dead, once-massive stars.
The newfound highly magnetic pulsar has a surprisingly long rotation period, which is challenging the theoretical understanding of these objects, researchers report May 30 in Nature Astronomy. Dubbed PSR J0901-4046, this pulsar sweeps its lighthouse-like radio beam past Earth about every 76 seconds — three times slower than the previous record holder. While it’s an oddball, some of this newfound pulsar’s characteristics are common among its relatives. That means this object may help astronomers better connect the evolutionary phases among mysterious species in the neutron star menagerie.
Astronomers know of many types of neutron stars. Each one is the compact object left over after a massive star’s explosive death, but their characteristics can vary. A pulsar is a neutron star that astronomers detect at a regular interval thanks to its cosmic alignment: The star’s strong magnetic field produces beams of radio waves emanating from near the star’s poles, and every time one of those beams sweeps across Earth, astronomers can see a radio pulse.
The newfound, slowpoke pulsar sits in our galaxy, roughly 1,300 light-years away. Astrophysicist Manisha Caleb of the University of Sydney in Australia and her colleagues found it in data from the MeerKAT radio telescope outside Carnarvon, South Africa.
Further observations with MeerKAT revealed not only the pulsar’s slow, steady radio beat — a measure of how fast it spins — but also another important detail: The rate at which the spin slows as the pulsar ages. And those two bits of info revealed something odd about this pulsar. According to theory, it should not be emitting radio waves. And yet, it is.
As neutron stars age, they lose energy and spin more slowly. According to calculations, “at some point, they’ve exhausted all their energy, and they cease to emit any sort of emission,” Caleb says. They’ve become dead to detectors.
A pulsar’s rotation period and the slowdown of its spin relates to the strength of its magnetic field, which accelerates subatomic particles streaming from the star and, in turn, generates radio waves. Any neutron stars spinning as slowly as PSR J0901-4046 are in this stellar “graveyard” and shouldn’t produce radio signals.
But “we just keep finding weirder and weirder pulsars that chip away at that understanding,” says astrophysicist Maura McLaughlin of West Virginia University in Morgantown, who wasn’t involved with this work.
The newfound pulsar could be its own unique species of neutron star. But in some ways, it also looks a bit familiar, Caleb says. She and her colleagues calculated the pulsar’s magnetic field from the rate its spin is slowing, and it’s incredibly strong, similar to magnetars (SN: 9/17/02). This hints that PSR J0901-4046 could be what’s known as a “quiescent magnetar,” which is a pulsar with very strong magnetic fields that occasionally emits brilliantly energetic bursts of X-rays or other radiation. “We’re going to need either X-ray emission or [ultraviolet] observations to confirm whether it is indeed a magnetar or a pulsar,” she says.
The discovery team still has additional observations to analyze. “We do have a truckload more data on it,” says astrophysicist Ian Heywood of the University of Oxford. The researchers are looking at how the object’s brightness is changing over time and whether its spin abruptly changes, or “glitches.”
The astronomers also are altering their automated computer programs, which scan the radio data and flag intriguing signals, to look for these longer-duration spin periods — or even weirder and more mysterious neutron star phenomena. “The sweet thing about astronomy, for me, is what’s out there waiting for us to find,” Heywood says.
Surviving on blood alone is no picnic. But a handful of genetic tweaks may have helped vampire bats evolve to become the only mammal known to feed exclusively on the stuff.
These bats have developed a range of physiological and behavioral strategies to exist on a blood-only diet. The genetic picture behind this sanguivorous behavior, however, is still blurry. But 13 genes that the bats appear to have lost over time could underpin some of the behavior, researchers report March 25 in Science Advances.
“Sometimes losing genes in evolutionary time frames can actually be adaptive or beneficial,” says Michael Hiller, a genomicist now at the Senckenberg Society for Nature Research in Frankfurt. Hiller and his colleagues pieced together the genetic instruction book of the common vampire bat (Desmodus rotundus) and compared it with the genomes of 26 other bat species, including six from the same family as vampire bats. The team then searched for genes in D. rotundus that had either been lost entirely or inactivated through mutations.
Of the 13 missing genes, three had been previously reported in vampire bats. These genes are associated with sweet and bitter taste receptors in other animals, meaning vampire bats probably have a diminished sense of taste — all the better for drinking blood. The other 10 lost genes are newly identified in the bats, and the researchers propose several ideas about how the absence of these genes could support a blood-rich diet.
Some of the genes help to raise levels of insulin in the body and convert ingested sugar into a form that can be stored. Given the low sugar content of blood, this processing and storage system may be less active in vampire bats and the genes probably aren’t that useful anymore. Another gene is linked in other mammals to gastric acid production, which helps break down solid food. That gene may have been lost as the vampire bat stomach evolved to mostly store and absorb fluid.
One of the other lost genes inhibits the uptake of iron in gastrointestinal cells. Blood is low in calories yet rich in iron. Vampire bats must drink up to 1.4 times their own weight during each feed, and, in doing so, ingest a potentially harmful amount of iron. Gastrointestinal cells are regularly shed in the vampire bat gut, so by losing that gene, the bats may be absorbing huge amounts of iron and quickly excreting it to avoid an overload — an idea supported by previous research.
One lost gene could even be linked to vampire bats’ remarkable cognitive abilities, the researchers suggest. Because the bats are susceptible to starvation, they share regurgitated blood and are more likely to do so with bats that previously donated to themselves (SN: 11/19/15). Vampire bats also form long-term bonds and even feed with their friends in the wild (SN: 10/31/19; SN: 9/23/21). In other animals, this gene is involved in breaking down a compound produced by nerve cells that is linked to learning and memory — traits thought to be necessary for the vampire bats’ social abilities.
“I think there are some compelling hypotheses there,” says David Liberles, an evolutionary genomicist at Temple University in Philadelphia who wasn’t involved in the study. It would be interesting to see if these genes were also lost in the other two species of vampire bats, he says, as they feed more on the blood of birds, while D. rotundus prefers to imbibe from mammals.
Whether the diet caused these changes, or vice versa, isn’t known. Either way, it was probably a gradual process over millions of years, Hiller says. “Maybe they started drinking more and more blood, and then you have time to better adapt to this very challenging diet.”
Julius Nziza still remembers the moment vividly. Just before dawn on a chilly January morning in 2019, he and his team gently extracted a tiny brown bat from a net purposely strung to catch the nocturnal fliers. A moment later, the researchers’ whoops and hollers pierced the heavy mist blanketing Rwanda’s Nyungwe National Park. The team had just laid eyes on a Hill’s horseshoe bat (Rhinolophus hilli), which scientists hadn’t seen for nearly four decades.
Nziza, a wildlife veterinarian at Gorilla Doctors in Musanze, Rwanda, and a self-described “bat champion,” had been looking for the critically endangered R. hilli since 2013. For several years, Nziza and Paul Webala from Maasai Mara University in Narok, Kenya, with the help of Nyungwe park rangers, surveyed the forest for spots where the bats might frequent. They didn’t find R. hilli, but it helped them narrow where to keep looking.
In 2019, the team decided to concentrate on roughly four square kilometers in a high-elevation region of the forest where R. hilli had last been spotted in 1981. Accompanied by an international team of researchers, Nziza and Webala set out for a 10-day expedition in search of the elusive bat. It wasn’t rainy season yet, but the weather was already starting to turn. “It was very, very, very cold,” Nziza recalls. Every night, from sunset until close to midnight, the researchers stretched nets across trails, where bats are most likely to fly, and kept watch. Then, after a few hours of rest, they woke early to check the traps again. It was cold enough that the bats could die if stuck too long.
At 4 a.m. on the fourth day, the researchers caught a bat with the distinctive horseshoe-shaped nose of all horseshoe bat species. But it looked slightly different from others they had captured. This one had darker fur and a pointed tip on its nose.
Everyone began shouting: “This is it!” The researchers felt “almost 99 percent sure” they had found the lost bat. “We had a couple beers in the evening,” Nziza says. “It was worth celebration.” To be 100 percent sure, though, the team needed to compare its specimen to past ones of R. hilli. Fortunately, there were two in museums in Europe.
That’s because this isn’t the first time that R. hilli was lost, then found, to science. Victor van Cakenberghe, a retired taxonomist at the University of Antwerp in Belgium, rediscovered R. hilli 17 years after it was first seen in 1964. He says he still remembers finding the bat tangled in a mist net strung across a river. He kept the specimen and brought it back to a Belgian museum.
Nearly 40 years later, Nziza and colleagues compared the measurements of their bat, which was released into the wild, to the preserved bat. At long last, it can be confidently said that R. hilli was rediscovered again, researchers report March 11 in a preprint submitted to Biodiversity Data Journal.
And, for the first time ever, the scientists recorded R. hilli’s echolocation call. Now, the rangers can use acoustic detectors to keep an eye — or rather, an ear — on the bat (SN: 10/23/20). In nine months, they’ve already captured R. hilli calls from eight different locations in the same small area. The team published its data to the open-access Global Biodiversity Information Facility in hopes of speeding up conservation efforts for the bat. Africa is home to over 20 percent of the world’s bats, but with a longstanding research focus on bats in Europe and the Americas, little is known about African bat species.
“It’s a whole new thing,” Nziza says. “That’s why everybody’s excited.”
You can never have too much ice cream, but you can have too much ice in your ice cream. Adding plant-based nanocrystals to the frozen treat could help solve that problem, researchers reported March 20 at the American Chemical Society spring meeting in San Diego.
Ice cream contains tiny ice crystals that grow bigger when natural temperature fluctuations in the freezer cause them to melt and recrystallize. Stabilizers in ice cream — typically guar gum or locust bean gum — help inhibit crystal growth, but don’t completely stop it. And once ice crystals hit 50 micrometers in diameter, ice cream takes on an unpleasant, coarse, grainy texture.
Cellulose nanocrystals, or CNCs, which are derived from wood pulp, have properties similar to the gums, says Tao Wu, a food scientist at the University of Tennessee in Knoxville. They also share similarities with antifreeze proteins, produced by some animals to help them survive subzero temperatures. Antifreeze proteins work by binding to the surface of ice crystals, inhibiting growth more effectively than gums — but they are also extremely expensive. CNCs might work similarly to antifreeze proteins but at a fraction of the cost, Wu and his colleagues thought.
An experiment with a sucrose solution — a simplified ice cream proxy — and CNCs showed that after 24 hours, the ice crystals completely stopped growing. A week later, the ice crystals remained at 25 micrometers, well beneath the threshold of ice crystal crunchiness. In a similar experiment with guar gum, ice crystals grew to 50 micrometers in just three days. “That by itself suggests that nanocrystals are a lot more potent than the gums,” says Richard Hartel, a food engineer at the University of Wisconsin–Madison, who was not involved in the research. If CNCs do function the same way as antifreeze proteins, they’re a promising alternative to current stabilizers, he says. But that still needs to be proven.
Until that happens, you continue to have a good excuse to eat your ice cream quickly: You wouldn’t want large ice crystals to form, after all.
