| 24 February 2026 |
| Today’s Visualized examines the “alien” whiskers of elephants. But first, catch up on the latest science news, including a stent that grows with a young heart and an almost invisible “dark galaxy.” |
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| Animals | News from Science |
| Whoa! When horses whinny, they whistle and sing at the same time |
| A horse’s whinny combines a piercing, high-pitched screech with a lower, guttural rumble. But the two components of the call differ not just in tone—they’re made in entirely different ways. The lower tone emerges when the horse vibrates its vocal folds, much as a human does to speak. To make the high note, the horse whistles . The observation makes the horse the only mammal known to whistle and produce a vocal fold vibration at the same time.
Mammals typically vocalize by exhaling air past vocal folds in the throat to make them vibrate. Generally, larger animals have heavier vocal folds that vibrate at lower frequencies. However, when a horse whinnies, the 500-kilogram animal emits a screech as high-pitched as that of a tea kettle. “It’s way too high for their body size,” noted behavioral ecologist Elodie Briefer.
To see how horses manage this impressive feat, Briefer called up her sister Sabrina Briefer Freymond, an equine ethologist, to organize tests with endoscopes on 10 stallions. The researchers found that a whinny starts with a high note associated with a squeeze in the larynx, which is later joined by vocal fold vibrations and a low note. Could that squeeze create a whistle?
To find out, Briefer and her colleagues pumped air and helium through dissected horse larynxes. When you blow helium through a whistle instead of air, its frequency rises. In contrast, vocal folds vibrate at the same fundamental frequency and multiples of it, known as overtones, regardless of the gas flowing by. In the experiment, the high-pitched noise emitted by the horse larynxes climbed higher with helium, confirming it’s a whistle. Meanwhile, the frequencies in the low-pitched noises remained steady, revealing they came from vibrating vocal folds. |
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| Medicine | Science Advances |
| A heart valve replacement that keeps up with kids |
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| The springlike stent in its expanded state (dime for scale). Ventura et al./Science Advances (2026) |
| When babies are born with certain heart defects, doctors have to perform valve replacements within their first months of life. But infants grow fast and their hearts double in diameter by age six, requiring multiple open-heart surgeries to upgrade the size of the implant. Now, scientists are proposing a heart valve replacement with a stent that expands on its own as a child grows.
The device, described in Science Advances, relies on a stent made from nitinol, a superelastic metal commonly used in cardiovascular implants. But instead of being stretched later with a balloon catheter, as many expandable valves are, this one is designed to act like a gentle spring. It is designed to be first implanted in a compressed state, around 7 millimeters wide. Then, as the heart grows and the surrounding tissue gradually relaxes its grip, the stent slowly pushes outward, expanding over time. In piglets, the implant widened from about 8 to 9 millimeters at surgery to roughly 13 millimeters after 6 weeks, without additional surgeries or procedures.
There was one complication. By week six, some piglets developed tissue overgrowth, or pannus, at the valve’s inflow region, narrowing the opening and increasing pressure across the valve. Imaging showed the metal stent itself kept expanding uniformly, as designed. The issue appeared to be the biological response to the valve graft material—a cryopreserved human femoral vein—rather than a failure of the spring mechanism. Future iterations may explore alternative materials.
The study is an early preclinical demonstration of the new device; longer-term durability, immunological responses, and other improvements will be further researched in the future. If the strategy ultimately works in humans, a growth-adaptive valve could spare young patients one or more major operations during early childhood. |
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| Astronomy | News from Science |
| Astronomers spot nearly invisible ‘dark galaxy’ |
| Over the past few decades, astronomers have found an increasing number of galaxies that don’t seem to shine brightly like our Milky Way, including some that are barely visible at all. Still, a team has found what they call a candidate “dark galaxy”—one made up of more than 99.9% dark matter, the mysterious stuff thought to provide the gravitational heft to hold galaxies together.
How do you find a galaxy that is almost invisible? Astronomers had noticed that many of these low surface brightness galaxies have clumps of stars called globular clusters grouped around them. Globular clusters are like mini-galaxies, spherical in shape with tens of thousands to millions of stars. They are thought to be the first stage of star formation in galaxies—the Milky Way has more than 150 around its disk. So, a team set out to find dark galaxies by scanning an archive of images taken by the Hubble Space Telescope. They searched for statistically unlikely clumps of globular clusters and found a close-knit group of four globular clusters which, on closer examination, had a very faint diffuse glow around them—the sign of a galaxy with only a sprinkling of other stars.
The discovery supports the theory that these are galaxies that were stopped in their tracks during star formation by other nearby galaxies creating a hostile environment for creating stars. “Their initial burst of star formation was just these globular clusters and then, because they’re in this really extreme environment, their hydrogen gas got stripped away so the … star formation just basically got quenched,” explained team leader Dayi Li. |
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| Mass timber is poised to reshape construction |
| A new wood product called mass timber could help meet the demand for environmentally conscious building materials. The University of Arkansas Fay Jones School of Architecture and Design is educating the next generation in mass-timber innovation. |
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| Visualized |
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| A zookeeper feeling the unusual whiskers that cover an Asian elephant’s trunk. © MPI-IS/A. Posada and Heidelberg Zoo |
| If you were to “hold hands” with an elephant, you’d feel that its trunk is ridged, wrinkled and thick-skinned. But you might also feel the roughly 1000 whiskers threaded across the trunk’s surface—fine, bristled filaments used to extend the elephant’s sense of touch.
Unlike rats or mice, elephants lack the tiny muscles required for “whisking” or moving these structures around. So, scientists hypothesized that whatever sensing happens must be built directly into the material of the hair itself. By analyzing the whiskers, from the scale of whole hairs down to the nanostructure of their walls, researchers characterized how their porosity and stiffness contribute to the elephant’s great tactile acuity.
The study found that the whiskers transition from a stiff base to a soft, rubberlike tip in a functional gradient that differs from the uniformly stiff whiskers of rats and mice. |
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| Functional gradients give elephant whiskers physical intelligence. Schulz et al./Science (2026) |
| Microcomputed tomography revealed thick, bladelike whiskers with flattened cross-sections, hollow bases and long internal channels resembling the porous architecture of sheep horns and horse hooves. That porous base reduces mass and helps absorb impact, which is crucial for animals that forage for hours each day and cannot regrow lost whiskers.
By giving the whisker microscopic pokes, the team showed that at the nanoscale the whisker wall behaves like two different materials along its length. Near the root, it acts like a stiff, plastic-like polymer, but near the tip, it’s more like a resilient elastomer that springs back without permanent deformation. |
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| Katherine Kuchenbecker (left) and Andrew Schulz holding the “whisker wand”: a 3D-printed replica of an elephant’s trunk hair. © MPI-IS/W. Scheible |
| In adults, stiffness shifts dramatically from base to tip, creating what engineers call a functional gradient. To understand what that meant physically, the researchers 3D-printed an enlarged “whisker wand” with a rigid dark base and a soft transparent tip. Co-author Katherine Kuchenbecker carried it through the halls of the Institute, gently tapping columns and railings. “I didn’t need to look to know where the contact was happening; I could just feel it,” she said.
By running computer simulations, the team confirmed that the stiff-to-soft transition amplifies differences in vibration depending on where along the whisker contact occurs, effectively creating a built-in map of touch. Engineers call this phenomenon “embodied intelligence.” For elephants, it means that even without whisking, each hair can already tell where the world touches back.
“Elephant whiskers are aliens,” Andrew Schulz, a mechanical engineer and first author on the paper, told The New York Times. |
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| Unconforming mystery |
| The Great Unconformity—where the swath of history between more than a billion years ago and 500 million years ago is just missing from the geological record—has puzzled earth scientists for more than a century. Now, a team proposes that the slate was set up to be wiped clean two billion years or so ago by the formation and breakup of an older supercontinent known as Columbia. Though other experts remain unconvinced. |
| PNAS Paper | Read more at News from Science |
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| Ancient mass grave a power play |
| The 77 bodies of women and children unearthed in Serbia in the 1970s, at a site dubbed the Gomolava grave, have long been considered a sign of a catastrophe—a terrible disease, for instance. But several signs of foul play, and the fact that the people are largely unrelated to one another, point to another explanation: a grisly show of power. “It’s a bunch of people from different villages, all killed in the same place, at the same time,” explained one archaeologist. Whoever perpetrated the killings “[was] trying to show they have the power to dispose of things that would be valuable to keep.” |
| Nature Human Behavior Paper | Read more at News from Science |
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| NIH funding plummeted last year |
| Funding rates for those seeking research grants from the U.S. National Institutes of Health dropped sharply last year—in part because of a new policy that requires NIH to fund multiyear grants up front in a single lump sum, which likely is making it harder for early-career researchers to win a grant, the agency acknowledged in a recent blog post. “Gotta admit, I’m somewhat heartened by this recent post,” one cell biologist wrote; “not WHAT it is reporting but that it IS reporting.” |
| NIH BLOG POST | Read more at ScienceInsider |
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I think it is unfair to ask him to do the job … I don’t see why the White House would put him in a position with such a high risk of failure.
—Neal Lane, Rice University |
| ScienceInsider | 20 February 2026 | Jeffrey Mervis |
| U.S. President Donald Trump’s choice to lead the National Science Foundation (NSF), financier Jim O’Neill, lacks an advanced science degree and any experience managing a large basic research enterprise. That could lead to problems for an agency that traditionally relies heavily on that community to shape its scientific agenda and choose the best ideas to fund. |
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| Last but not least |
| When I tell my 8-year-old daughter I love her, she confidently states that she loves me more. After a back and forth of increasing volumes, I say that my love for her is infinite, and she proudly ends the argument by saying she loves me “infinity times infinity times infinity times infinity times infinity plus infinite love.” I have been claiming that you can’t have an infinity bigger than infinity… but I guess I’m going to have to admit defeat. |
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| Christie Wilcox, Editor, ScienceAdviser
With contributions from Christa Lesté-Lasserre, Ana Georgescu, and Daniel Clery
Do you have a burning science question you can’t seem to find a good answer for? Submit it to Ask Science! Selected questions will receive responses from Science editors right here in ScienceAdviser. |
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