New experiments seem to bolster a recently retracted claim of room-temperature superconductivity in a blend of hydrogen, sulfur and a bit of carbon squeezed to enormous pressures in a diamond anvil like this one.
It may be too soon to mourn the demise of a room-temperature superconductivity claim.
On September 26, the journal Nature retracted a paper describing a material that seemed to turn into a superconductor at a cozy 15° Celsius ( SN: 10/14/20) . The notice rattled many people in the field. But a new experiment performed just days after the retraction supports the world-record temperature claim, say an eyewitness and others familiar with the experiment.
Superconductors carry electricity with no resistance, which means they’re useful for efficiently transmitting energy. They could save enormous amounts of energy that’s wasted in conventional metal wires. Currently they are used to create powerful magnetic fields for medical imaging and particle physics experiments, as well as serving as components in high-performance circuity and even levitating high-speed trains. But to work, superconducting materials generally must be cooled far below 0° C, and many to temperatures close to absolute zero, or -273° C.
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When researchers announced in 2020 that a sample made of hydrogen, sulfur and a bit of carbon became a superconductor at record-shattering temperatures , dreams of room-temperature superconducting seemed to be on the verge of coming true. One hitch was that the material had to be under enormous pressures, about 2.6 million times atmospheric pressures — roughly the pressure found in parts of Earth’s core. Still, the discovery hailed a potential scientific and technological revolution.
In the two years since, controversy has swirled around the report. The maelstrom is centered on the way the researchers prepared and processed data that showed changes in a magnetic property known as susceptibility. Ultimately, editors at Nature took the unusual step of retracting the paper despite the researchers’ objections. “We have now established that some key data processing steps … used a non-standard, user-defined procedure,” write the editors at Nature in the retraction. “The details of the procedure were not specified in the paper and the validity of the background subtraction has subsequently been called into question.”
The new experiment isn’t a duplicate of the one reported in the retracted paper, but the researchers replicated a portion of their research that raised red flags in the scientific community.
Ranga Dias, a physicist at the University of Rochester who headed the research on the now-retracted paper, led the new measurements at Argonne National Laboratory’s Advanced Photon Source in Lemont, Ill. “We have been working on this experiment for almost six months, building and reconfirming the correct methodology,” Dias says. “I would say the data we obtained at Argonne is more compelling, not just comparable,” to the data in the retracted Nature paper.
“The experiment took place over two days, September 27 and 28,” says physicist Nilesh Salke of the University of Illinois Chicago, who was not affiliated with the original research. Salke’s role at Argonne involved probing a sample of the material in question with X-rays while it was exhibiting magnetic susceptibility associated with high-temperature superconductivity. “We saw the first susceptibility signal on September 27, consistent with the claims reported in the retracted Nature paper.”
This latest twist is unlikely to put an end to the controversy that came with the initial claim, at least in the mind of physicist Jorge Hirsch of the University of California, San Diego. Hirsch has been one of the most vocal critics of the room-temperature superconductivity claim.
“I didn’t know it would be retracted, but was hoping it would be retracted,” says Hirsch, who was not affiliated with either the original or new experiment. He says he asked the authors for the raw data from the earlier study one month after it was published, but he was refused. “The authors said, ‘No we cannot give you the data because our lawyers said that it would affect our patent rights.’”
With intervention from Nature , Hirsch eventually got the numbers. What he saw disturbed him. Hirsch is skeptical that high-temperature superconductivity is possible in these sorts of hydrogen-based materials in general, but says he is objecting based on the way the data were handled.
“There were real problems between the raw data and the published data,” Hirsch says. He believes that Nature ’s retraction doesn’t go far enough. “It’s not that the data were not properly processed.” Along with physicist Dirk van der Marel of the University of Geneva, Hirsch delves into problems with the data in a paper published September 15 in the International Journal of Modern Physics B . “Our analysis proves mathematically that the raw data were not measured in the laboratory. They were fabricated.”
Dias and colleagues deny any impropriety in their data or analysis and are moving forward with experiments like the one at Argonne. But that work awaits peer review. For now, Nature ’s retraction bolsters existing doubts around room-temperature superconductivity.
“In the end, all of this has to be validated by different groups getting the answer,” Hirsch says.
James Riordon is a freelance science writer who covers physics, math, astronomy and occasional lifestyle stories.
Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).
A kind of teenager mosquito can suddenly shoot its head forward from its body — stretching its neck into a skinny cord — to bite into another youngster. And that’s just one of the ways young mosquitoes kill other mosquitoes, a new study shows.
Over decades, scientist-cinematographer Robert Hancock and colleagues have filmed attacks by these Psorophora ciliata and two other kinds of predatory mosquito larvae in unusual detail. Launching heads evolved independently in two of the kinds, he and colleagues say in their new study.
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The most dramatic pounce on film may be the neck-stretching snatch by the Psorophora larva. It might power this lunge by squeezing a rush of fluid to the head. When Hancock watches the mosquito’s body, segmented a bit like a string of alphabet-block beads, he can see two segments scrunching inward “accordion-like,” as if squirting fluid forward as the head shoots out.
Launching the head to reach the prey is one thing, but catching hold is another problem. The newly released video gives a clear view of a pair of brushes, one on each side of the head, that help with the grasp. As the head nears its victim, the brushes fan out into what the researchers call a “flimsy basketlike arrangement” that folds around the doomed prey.
Such an attack may startle people thinking of mosquito bites just as stealthy hypodermic blood-sucks. That’s the adult bite from females craving a nutritional supplement for egg-laying. Mosquito eggs, however, hatch in water, and larvae don’t assume their dandelion-wisp flying form for weeks. During the aquatic phase, these larvae don’t look, or dine, like adult forms at all.
Larvae don’t bite people, and many just filter out edible crumbs afloat in water. The meat eaters, however, pounce so fast that the human brain can’t parse it. Hancock has been fascinated ever since he was in a class in the 1980s seeing only a blur through the microscope as he tried to describe the feeding behavior. The Toxorhynchites mosquitoes that frustrated him then have turned out to be one of the groups that evolved head-launching larvae.
“ If there’s any mosquito for all the mosquito haters to actually maybe not love but like, it’s Toxorhynchites ,” says Hancock, now at Metropolitan State University of Denver. As iridescent adults they’re vegans, feeding largely on flower nectar. For larvae, it’s all meat, mostly other mosquitoes. Plus, he says, “They’re large, and they’re gorgeous.”
The new study found that the launch doesn’t extend as far as a head length, but Toxorhynchites attacks the prey larva vigorously. In the videos, “by the time you would catch sight of it, there would be like a half of larva … as it shoved this thing in like it was a hot dog eating contest,” Hancock says.
He and colleagues also caught on film a third kind of meat-eating mosquito, Sabethes , which are more flexitarian than carnivore. They still eat their meat at their head end, but the danger of getting snagged comes from their rear, the researchers’ videos show. Like many mosquito larvae, they often dangle head down in the water, taking in oxygen through a flexible siphon. It turns out that the breathing tube doubles as a type of food hook, capable of snaring a target in only several milliseconds.
“The thing about Sabethes is that they’re probably more like murderers because they really don’t ingest and consume entire prey larvae like the other two,” Hancock says. Feeding tests show that the insects do gain at least some nutrition from the nibbling.
A human watching the larvae hunt may wonder why we put so much money and chemistry into trying to kill the pests when their own tiny relatives do it so brilliantly. For one thing, mosquito larvae stay underwater, says entomologist Don Yee of the University of Southern Mississippi in Hattiesburg, who wasn’t involved in the study. The two neck-stretcher groups can’t lift into the air and fly to the next water-filled tire or tree hole. There, a Toxorhynchites , for instance, “likely would consume all other larvae,” he says. “[H]owever, there may be hundreds of such containers in the area.”
In contrast, the neck-stretching Psorophora mosquitoes live in larger bodies of water and could theoretically have more of an effect at knocking back mosquito numbers, Yee says. But under natural circumstances, the predators are unlikely to crash mosquito populations as humans would want. Yee compares it to the African savanna. In photos, “you can see how many wildebeest there are. The lions can’t really control them.” In nature, after all, predators that thrive don’t wipe out their own prey.
Susan Milius is the life sciences writer, covering organismal biology and evolution, and has a special passion for plants, fungi and invertebrates. She studied biology and English literature.
Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).
Experiments on a bizarre feature of quantum physics known as entanglement (illustrated here as two objects entangled into one) have netted the 2022 Nobel Prize in physics. When two particles are entangled, what happens to one determines what happens to the other — even if the particles are far apart.
Tests of quantum weirdness and its potential real-world applications have been recognized with the 2022 Nobel Prize in physics.
At some level we are all subject to quantum rules that even Albert Einstein struggled to come to terms with. For the most part, these rules play out behind the scenes in transistors that make up computer chips, lasers and even in the chemistry of atoms and molecules in materials all around us. Applications that stem from this year’s Nobel Prize take advantage of quantum features at larger scales. They include absolutely secure communications and quantum computers that may eventually solve problems that no conceivable conventional computer could complete in the lifetime of the universe.
This year’s prize is shared among three physicists. Alain Aspect and John Clauser confirmed that the rules of quantum mechanics, as weird and difficult to believe as they are, really do rule the world, while Anton Zeilinger has taken advantage of strange quantum behavior to develop rudimentary applications that no conventional technology can match. Each laureate will take home a third of the prize money, which totals 10 million Swedish kronor, worth roughly $915,000 as of October 4.
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“Today, we honor three physicists whose pioneering experiments showed us that the strange world of entanglement … is not just the micro-world of atoms, and certainly not the virtual world of science fiction or mysticism, but it’s the real world that we all live in,” said Thors Hans Hansson, a member of the Nobel Committee for Physics, at a press conference announcing the award on October 4 at the Royal Swedish Academy of Sciences ( SN: 11/5/10 ).
“It was certainly very exciting to learn about the three laureates,” says physicist Jerry Chow of IBM Quantum in Yorktown Heights, N.Y. “Aspect, Zeilinger and Clauser — they’re all very, very well known in our quantum community, and their work is something that’s really been a big part of many people’s research efforts over many years.”
Aspect, of the Université Paris-Saclay and École Polytechnique in France, and Clauser, who now runs a company in California, showed that there are no secret back channels of communication that explain how two particles can exist as a single entity, even though they are far apart ( SN: 12/29/14 ).
The experiments of Zeilinger, of the University of Vienna, that rely on that quantum behavior include demonstrations of communications, absolutely secure encryption and components crucial for quantum computers. He pioneered another, widely misunderstood, application — quantum teleportation. Unlike the teleportation of people and objects in science fiction, the effect involves the perfect transmission of information about a quantum object from one place to another.
“I was always interested in quantum mechanics from the very first moments when I read about it,” Zeilinger said via phone at the news conference announcing the award. “I was actually struck by some of the theoretical predictions, because they did not fit the usual intuitions which one might have.”
The discovery of quantum behavior that rules the world at small scales, like the motion of an electron around an atom, revolutionized physics at the beginning of the 20th century. Many leading scientists, most famously including Einstein, acknowledged that quantum theories worked, but argued that they couldn’t be the true description of the world because they involved, at best, calculating the probabilities that something would happen ( SN: 1/12/22 ). To Einstein, this meant that there was some hidden information that experiments were too crude to uncover.
Others believed that quantum behavior, derogatively called weirdness, though difficult to understand, had no secret ways of transmitting information. It was largely a matter of opinion and debate until physicist John Bell proposed a test in the 1960s to prove that there were no hidden channels of communication among quantum objects ( SN: 12/29/14 ). At the time it wasn’t clear that an experiment to perform the test was possible.
Clauser was the first to develop a practical experiment to confirm Bell’s test, although there remained loopholes his experiment couldn’t check that left room for doubt. (His interest in science developed early. In 1959 and 1960, Clauser competed in the National Science Fair , now known as the International Science and Engineering Fair ( SN: 5/23/59 ). The fair is run by the Society for Science, which publishes Science News .)
Aspect took the idea further to eliminate any chance that quantum mechanics had some hidden underpinnings of classical physics ( SN: 1/11/86 ). The experiments of Clauser and Aspect involved creating pairs of photons that were entangled, meaning that they were essentially a single object. As the photons moved in different directions, they remained entangled. That is, they continue to exist as a single, extended object. Measuring the characteristics of one instantly reveals characteristics of the other, no matter how far apart they may be.
Entanglement is a delicate state of affairs and is difficult to maintain, but the results of the experiments of Clauser and Aspect show that quantum effects cannot be explained with any hidden variables that would be signs of non-quantum underpinnings.
To Chow, the significance of this research is twofold. “There’s really an element of showing, from a philosophical point, that quantum mechanics is real,” he says. “But then, from the more practical standpoint … this same beautiful theory of quantum mechanics gives a different set of rules by which information is processed.” That, in turn, opens up new avenues for next-generation technologies like quantum computers and communications ( SN: 12/3/20 ).
Zeilinger’s experiments take advantage of entanglement to achieve feats that would not be possible without the effects that Clauser and Aspect confirmed. He has extended the experiments from the lab to intercontinental distances , opening up the possibility that entanglement can be put to practical use ( SN: 5/31/12 ). Because interacting with one of a pair of entangled particles affects the other, they can become key components in secure communications and encryption. An outsider trying to listen in on a quantum communique would be revealed because they would break the entanglement as they snooped.
Quantum computers that rely on entangled particles have also become a topic of active research. Instead of the ones and zeros of conventional computers, quantum computers encode information and perform calculations that are blends of both one and zero. In theory, they can perform some calculations that no digital computer could ever match. Zeilinger’s quantum teleportation experiments offer a route to transfer the information that such quantum computers rely on ( SN: 1/17/98 ).
“This [award] is a very nice and positive surprise to me,” says Nicolas Gisin, a physicist at the University of Geneva in Switzerland. “This prize is very well-deserved, but comes a bit late. Most of that work was done in the [1970s and 1980s], but the Nobel Committee was very slow, and now is rushing after the boom of quantum technologies.”
That boom is happening on a global scale, Gisin says. “In the U.S. and in Europe and in China, billions — literally billions of dollars are poured into this field. So, it’s changing completely,” he says. “Instead of having a few individuals pioneering the field, now we have really huge crowds of physicists and engineers that work together.”
Although some of the most esoteric quantum applications are in their infancy, the experiments of Clauser, Aspect and Zeilinger bring quantum mechanics, and its strange implications, to the macroscopic world. Their contributions validate some of the key, once controversial ideas of quantum mechanics and promise novel applications that may someday be commonplace in daily life, in ways that even Einstein couldn’t deny.
Maria Temming contributed reporting to this story.
James Riordon is a freelance science writer who covers physics, math, astronomy and occasional lifestyle stories.
Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).
When COVID-19 burst onto the global stage in 2020, it was deadly and disruptive. In the first weeks of January, researchers identified the cause: A coronavirus was to blame, a relative of the virus that caused the 2003 SARS outbreak. Echoes of what had happened nearly 20 years earlier — thousands were infected and at least 774 people died before the SARS outbreak was brought under control — sent ripples of anxiety throughout the virology world.
Scientists of all backgrounds rushed to understand the new scourge, dubbed SARS-CoV-2. Hospitals around the world were soon overwhelmed, and daily life for billions of people was thrown into disarray. Quarantine, isolation, N95 masks and social distancing entered our collective lexicon. Breathless , by science writer David Quammen, takes readers along on the ensuing two-year scientific roller coaster.
The book is a portrait of the virus — SARS-CoV-2’s early days in China, how decades of science helped researchers craft effective vaccines within a year, the arrival of highly mutated variants. It’s not about the societal upheaval or the public health failures (and successes). While Quammen acknowledges the importance of those aspects of the pandemic, he chooses to focus on the “firehose” of scientific studies — both good and bad — that drove our understanding of COVID-19.
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He dives deep into one of the pandemic’s most controversial questions: Where did SARS-CoV-2 come from? Nature or the lab? Quammen describes the saga in elaborate detail. First there were worries that some of the virus’s features appeared engineered. Those concerns were quickly dispelled when researchers found those features in viruses from wild bats and pangolins. Then there was the thought that workers in a lab studying bat viruses could have become accidentally infected and unknowingly spread the virus to others.
Rather than dismiss that accidental lab leak hypothesis, Quammen takes readers step by step through the genetic and epidemiological data. That includes recent evidence supporting the scenario that the virus emerged — perhaps in two separate jumps — from an unknown animal at the Huanan Seafood Wholesale Market in Wuhan, China. Through his conversations with experts in virus ecology and evolution, readers learn the nuances of how virologists do research and the controversies of gain-of-function studies that test what happens when viruses acquire new traits. Quammen’s conclusion: An accidental lab leak is not impossible. “But it seems unlikely.”
To understand the pandemic, Quammen draws on lessons learned from our previous run-ins with coronaviruses, including the SARS outbreak and the 2012 MERS outbreak in the Middle East ( SN: 12/28/13, p. 23 ). Part of his 2012 book Spillover focused on the bat origin of the SARS outbreak ( SN: 10/20/12, p. 30 ). That tome is unnervingly prescient. If the original SARS coronavirus had been most contagious before symptoms began, Quammen wrote in Spillover , officials would have had a much harder time ending the outbreak. “It would be a much darker story,” he wrote. But that’s exactly what happened with SARS-CoV-2. People can pass the virus to others before knowing they are sick, a trait that helped COVID-19 spiral out of control.
As a science journalist who has followed SARS-CoV-2 since its discovery, I found Breathless to be surprisingly cathartic. My memories of the last few years have blurred together. Breathless presents the sweeping scientific story of the pandemic, connecting puzzle pieces that at the time had felt so out of place.
Some readers may feel it’s too soon to scrutinize a pandemic that isn’t even over. But SARS-CoV-2 certainly won’t be the last harmful virus to emerge. Quammen puts the pandemic in the context of the coronavirus scares that came before to highlight how science builds on itself. And one thing is certain: There will be another. “There are many more fearsome viruses where SARS-CoV-2 came from,” he writes, “wherever that was.”
Buy Breathless from Bookshop.org. Science News is a Bookshop.org affiliate and will earn a commission on purchases made from links in this article.
Erin I. Garcia de Jesus is a staff writer at Science News . She holds a Ph.D. in microbiology from the University of Washington and a master’s in science communication from the University of California, Santa Cruz.
Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).
By incorporating Lego-like chemicals into sugars on the cell surface, scientists can snap on green-glowing or other molecules to track specific cells. Here, large surface proteins with chains of sugars (illustrated, yellow) are shown on the outside of a cancer cell.
Chemists Carolyn Bertozzi of Stanford University, Morten Meldal of the University of Copenhagen and Barry Sharpless of the Scripps Research Institute in La Jolla, Calif., will evenly split the prize for developing click chemistry and bioorthogonal chemistry, the Royal Swedish Academy of Sciences announced October 5 in a news conference in Stockholm. These tools allow scientists to easily construct complex molecules in the lab and inside living organisms.
“The good thing with this discovery is that it can be used for almost everything,” said Olof Ramström, a chemist at the University of Massachusetts Lowell and a member of the Nobel committee for chemistry. Applications include building drug molecules, polymers, new materials and tracking biomolecules among cells.
“We’re kind of at the tip of the iceberg already in terms of applications,” says Angela Wilson, president of the American Chemical Society. “I think this chemistry is going to revolutionize medicine in so many areas.”
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Around 20 years ago, Sharpless introduced “click chemistry” — a way to simply and quickly attach two compounds using certain connector molecules. But finding these Lego-like connector molecules that can bond together in a chemical reaction wasn’t easy. Working independently, Sharpless and Meldal discovered a solution.
By adding a smidge of copper to a mixture containing two other small molecules — called an azide and an alkyne — the scientists could rapidly snap the two molecules together into a ring-shaped chemical. Without the copper, the molecules would eventually combine, but sluggishly, Ramström said.
The reaction quickly “gained enormous interest across chemistry and related fields,” he added. Even though scientists would later discover a handful of other molecules that could snap together in the same fashion, that first reaction is considered the “crown jewel of click reactions.”
But while catalyzing reactions with copper may work fine in a glass beaker, the metal can harm living cells. Bertozzi discovered a way to do copper-free click chemistry, so scientists can now design chemical reactions inside of organisms without mucking up their normal cellular functions.
Bertozzi tricked cells into incorporating a click chemical into sugars decorating the cell’s surface. When scientists expose these cells to a different click chemical, a type of alkyne, the two can snap together, just like the molecules in Sharpless’ and Meldal’s reactions. By linking the alkyne to green-glowing molecules, scientists can illuminate the surfaces of cells.
“Imagine you could attach shining molecules to biomolecules in a living cell. Then you could follow them in a microscope and see where they are and how they move. This is what Carolyn Bertozzi did,” said Johan Åqvist, a theoretical chemist at Uppsala University in Sweden and chair of the Nobel committee for chemistry.
Bertozzi’s specialty has been studying sugar molecules, which “are incredibly difficult to work with,” says Leslie Vosshall, a neuroscientist at the Rockefeller University in New York City, who is the vice president and chief scientific officer at the Howard Hughes Medical Institute. Straightforward methods exist for looking at DNA, RNA and proteins, but not so much for sugars, she says. “Sugars are the dark matter of the cell.”
By targeting specific sugars on cell surfaces, scientists can develop new treatments. For instance, Bertozzi and her colleagues were able to target and deactivate sugars that were helping tumor cells hide from T cells in the body ( SN: 3/21/17 ).
“Carolyn is… one of the astonishingly few women in chemical biology,” Vosshall says. “Her lab has been a generative place that has inspired women chemists and put them out into the world.”
When awakened by the news around 3 a.m. Pacific Time, Bertozzi said, “I’m absolutely stunned. I’m sitting here and can hardly breathe.” Calling the middle-of-the-night phone call a shock is an understatement, she added. “I’m still not entirely positive that it’s real, but it’s getting realer by the minute.”
Bertozzi, Meldal and Sharpless will share the prize — 10 million Swedish kronor, roughly $917,000. The award is the second Nobel for Sharpless, who shared the prize in 2001 for his work on developing catalysts for oxidation reactions .
Meghan Rosen is a staff writer who reports on the life sciences for Science News . She earned a Ph.D. in biochemistry and molecular biology with an emphasis in biotechnology from the University of California, Davis, and later graduated from the science communication program at UC Santa Cruz.
Nikk Ogasa is a staff writer who focuses on the physical sciences for Science News . He has a master’s degree in geology from McGill University, and a master’s degree in science communication from the University of California, Santa Cruz.
Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).
Tiny Scleromochlus taylori , shown here in an artist’s rendition, was a bipedal, ground-dwelling reptile, and a close relative of pterosaurs, the iconic winged vertebrates of the Age of Dinosaurs.
A mysterious ground-dwelling reptile unearthed in a Scottish sandstone over 100 years ago turns out to be part of a famous flying family. Tiny Scleromochlus taylori was a close relative of pterosaurs , the winged reptiles that lived alongside the dinosaurs, researchers report online October 5 in Nature .
The finding lends support to the idea that pterosaurs — the first vertebrates to master powered flight — evolved from small, two-legged, speedy ancestors.
The study also offers an answer to a long-standing mystery: What, exactly, was S. taylori ? “It all boils down to the preservation of this animal,” says Davide Foffa, a paleontologist at National Museums Scotland in Edinburgh.
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S. taylori is known entirely from seven individuals preserved in rocks discovered in 1907, fossils that have been difficult to interpret. For one thing, there aren’t any actual bones, just impressions on the surrounding rock; the bones have long since winnowed away. Numerous studies have described and redescribed the creature based on these fossils. And those analyses have in turn suggested that S. taylori was most closely related to dinosaurs, or to pterosaurs, or even to crocodilian ancestors.
What was clear was that the little reptile, which lived about 230 million years ago, had a set of very odd body proportions, Foffa says. At less than 20 centimeters long, “it would fit on the palm of your hand,” but its head was very large for its body. It also had a short neck and long hind limbs. But that rough outline isn’t enough to identify the creature’s closest relatives; that requires finer details of skull, jaw, body proportions and more.
So Foffa and his colleagues used a noninvasive scanning technology called microcomputed tomography to collect previously inaccessible data from the fossils, from the length of its tail to the size of its foot bones to the shape of its jawline.
Some of the creature’s features — like its giant head — are similar to pterosaurs. Others, like the orientation of its lower jaw, aren’t much like pterosaurs at all, the team found. S. taylori didn’t have any identifiable adaptations for flying, jumping or living in trees, the team says. Instead, it was probably a runner.
One of the most important new insights is about the structure of the creature’s femur. It bore strong similarities to both pterosaurs and a group of small, ground-dwelling reptiles called lagerpetids. In particular, the bottom of the femur bone, where it would connect to the lower leg, bears a structure that is a hallmark of lagerpetids, Foffa says.
Taken together, the new data suggest that the creature was almost certainly a lagerpetid. Though lagerpetids didn’t fly, they and pterosaurs have recently been recognized as being very closely related , part of a group collectively called pterosauromorphs. The common ancestor of pterosauromorphs was likely a small, fast-running reptile.
S. taylori , which has features of both, may be a very early lagerpetid, evolving soon after those two pterosauromorph lineages split. That it turned out to have so many features present in both was “kind of a surprise,” says Martín Ezcurra, a paleontologist at the Argentine Museum of Natural Sciences in Buenos Aires who was not involved in the new study. But based on the reanalysis of the fossils, the conclusion that S. taylori was an early lagerpetid makes a lot of sense, he says.
Pterosaurs first appear in the fossil record about 220 million years ago, and their anatomy is distinct, including massive heads for their body sizes and super-elongated fourth digits which were part of their wings ( SN: 10/12/10 ). S. taylori has the big head, but its hands are still small, Ezcurra notes. “We’re missing several intermediate forms in between that bear features related to active flight,” he says. But this new analysis of old fossils does bring scientists just a little bit closer to the time when pterosaurs’ unique and highly flight-adapted bodies began to evolve ( SN: 7/22/21 ).
It’s difficult to say what such a proto-pterosaur might look like, says Hans Sues, a paleontologist at the Smithsonian Institution in Washington, D.C., who was not involved in the new study. “ Scleromochlus is a tiny animal, and it is conceivable that a related small-bodied form climbed around in trees and eventually gave rise to a proto-pterosaur — perhaps through an intermediate gliding stage.”
Carolyn Gramling is the earth & climate writer. She has bachelor’s degrees in geology and European history and a Ph.D. in marine geochemistry from MIT and the Woods Hole Oceanographic Institution.
Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).
