| 1 April 2026 |
| In today’s Visualized, the world’s most dangerous birds get their glow on. But first, catch up on the latest science news, including doubts about the supposed connection between oxygen and giant insects, and how satellite data revealed hidden details of a tsunami. |
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| Paleobiology | News from Science |
| When bugs were big |
| Back 300 million years ago, some bugs would have swatted you rather than the other way around. Gargantuan insects roamed and flew through primal swamps and forests, including the biggest insect ever documented: Meganeuropsis permiana, a dragonflylike critter with a 60-centimeter wingspan.
How did these ancient insects grow so big? The textbook answer is that they took advantage of abundant available oxygen—about 30% of Earth’s atmospheric air, compared with 21% today. By developing more respiratory tubes, called tracheoles, to deliver that gas to their muscles, they just grew and grew. To get bigger insects, the idea goes, you need more oxygen in the air and more tracheoles to effectively get it to the muscles.
But a study out last week in Nature undercuts that popular hypothesis. Researchers analyzed the respiratory anatomy of 44 species of modern flying insects of various sizes, scanning and plotting the relationship between body size and the number of oxygen-carrying tracheoles. They found that regardless of size, tracheoles made up less than 1% of the insects’ muscle volume.
Then, they looked at that same relationship in fossils from the colossal M. permiana and found that, just as in modern insects, its tracheoles would have constituted less than 1% of its muscles. That suggests that relative to their size, these ancient behemoths didn’t incorporate much more oxygen into their muscles than their more diminutive, modern relatives.
“This study places what may be the final nail in the coffin for the prevailing view that more oxygen made ancient insects bigger,” says paleontologist Caleb Gordon, who wasn’t involved in the new study. |
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| seismology | Science |
| Seeing a tsunami from the sky |
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| Using observations from the SWOT satellite, scientists were able to reconstruct a tsunami triggered by the 2025 Kamchatka earthquake. The path of the satellite is indicated by two parallel lines. bjarke nilsson |
| When a magnitude 8.8 earthquake struck off Russia’s Kamchatka Peninsula in July 2025, it generated a Pacific-spanning tsunami tracked by coastal gauges and deep-ocean sensors. But about 70 minutes after the quake began, a satellite passing roughly 600 kilometers from the epicenter captured something other instruments could not. In a study published in Science, researchers reconstructed a full, two-dimensional snapshot of the wave as it moved across the open ocean.
Although tsunamis are often associated with towering waves crashing onto shore, they pass almost unnoticed in the deep ocean; as slow-moving undulations they can span hundreds of kilometers but rise only timidly above the surrounding water. In this case, the tsunami measured only 20 to 50 centimeters in height. The data, collected by the Surface Water and Ocean Topography (SWOT) satellite, showed that the leading wave was followed by a series of shorter, trailing waves, with tens of kilometers in wavelength and slower speeds, lagging behind the main front and forming a dispersive wave train. This phenomenon has long been predicted but rarely observed. After filtering out longer background ocean waves, SWOT resolved this structure down to a few centimeters, revealing fine-scale patterns that conventional sensors either miss or capture only along a single line.
Short-wavelength waves are generated when an earthquake rupture reaches very shallow depths near the seafloor trench. By capturing this trailing signal across the entire wavefield, the satellite data pinpointed the tsunami’s origin within roughly 10 kilometers of the trench, reaching a level of precision not possible with land-based seismic data or sparse deep-water sensors. |
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| physics | Science |
| A supercool discovery |
| Most liquids behave similarly when cooled, becoming denser, harder to compress, and easier to heat up. Water, however, does the complete opposite.
When water is cooled below freezing to a “supercooled” state, there must be a “hidden reorganization of water molecules,” to account for this strange behavior, physical chemist Francesco Paesani wrote in a recent Science Perspective. This rearrangement should occur at a critical point, where one phase of water transitions to another.
To search for this elusive phase transition, scientists typically study temperatures between −42°C and −172°C, the “no man’s land” zone where water has a tendency to crystallize to ice within microseconds and evade observational techniques. Instead, the authors of a new study chose to begin with two phases of amorphous ice, one high-density and one low-density, that mirrored the liquid states they were trying to catch. They quickly heated the ice using nanosecond pulses of infrared light. When it melted to a liquid state for just a nanosecond, they probed its structure using an x-ray laser.
The team repeated the process at conditions below, near, and above the predicted critical point. Around −63°C and 1000 times the pressure of Earth’s atmosphere at sea level, they found success: a quick change in water’s density that indicated it was switching between high-density and low-density liquid states.
“For 20 years or more, many people were waiting to see direct evidence” of this elusive critical point, physicist Nicolas Giovambattista, who wasn’t involved in the new study, told Science News. “It’s amazing that it finally came.” |
| Read the Science Paper |
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| 2026 Canada Gairdner Awards Honour Breakthrough Science |
| Meet the 2026 laureates recognized for groundbreaking discoveries advancing human health, from fundamental biology to global health research, with advances that are transforming our understanding of disease and shaping the future of medicine. |
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| Visualized |
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| This cassowary would be right at home at a rave. Todd l. green |
| Often labeled “the world’s most dangerous birds,” cassowaries just got even more intriguing. These aggressive flightless birds have structures on top of their heads called casques, the purpose of which has long confused scientists. To the human eye, casques look fairly plain; new research published last month in Scientific Reports finds that this headgear fluoresces under ultraviolet light, possibly aiding the birds’ visual displays.
When researchers examined casques under UV light, they discovered that the structures’ outermost sheath of keratin—the same protein that makes our fingernails and hair—glowed, with different species of cassowaries each giving off a distinct pattern. Some fluoresced towards the front of their casques, some towards the back, and others throughout the entire structure. No matter the species, the glow theoretically fell in the range of wavelengths of light that cassowaries can see. |
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| There’s more to this bird than meets the eye. Todd l. green |
| Researchers note that biofluorescence like this typically requires specific lighting conditions—such as sunlight filtered through dense forest canopies—to be visible, meaning the effect may be most relevant in the cassowaries’ rainforest habitat.
Still, study co-author Todd Green says it’s not yet clear whether the birds can actually perceive differences in the patterns, and further behavioral studies are needed to determine whether cassowaries use the glowing casques to communicate. |
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| Most dangerous, or most iconic? todd l. green |
| While the casques’ exact function remains uncertain, Green says the height they add might help birds intimidate any intruders on their territories. He adds that this work may apply to all animals with mysterious head ornaments, not just cassowaries. “If we can come to understand what modern animals are using this strange headgear for,” he says, “we can take it back into the fossil record to better understand extinct dinosaurs.”
Green also hopes that this discovery will serve as a sort of fingerprinting of individual wild cassowaries for researchers. “With the biofluorescence alone, we may be able to have better contrasted patterns which we can use to identify individuals within a species at a field site,” he says. |
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| Turtle tracking |
| Earlier this month, scientists deployed the first satellite tag on an endangered leatherback sea turtle in Ecuador. The team hopes to discover where these endangered animals are most vulnerable to threats from fishing activity. |
| Read more at Inside Climate News |
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| Big threat for small birds |
| Researchers warn that the merlin, Britain’s smallest bird of prey, is one of 200 species at risk of extinction in the event of an environmental worst-case scenario. |
| Nature Communications Paper | Read more at The Guardian |
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| On life support |
| The Agency for Healthcare Research and Quality—a small federal agency with a focus on studying patient care—appears to be on its last legs, but supporters are pushing the government to revive it. |
| Read more at ScienceInsider |
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| Our assumption that information is likely wrong, until we see reasonable evidence otherwise, is part of what makes us successful as scientists. Now, we just need to apply it to citations as well. |
| EXPERIMENTAL ERROR | 30 March 2026 | adam ruben |
| When artificial intelligence hallucinates convincing—and totally bogus—citations, a healthy dose of skepticism may be a researcher’s most powerful tool. |
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| Last but not least |
| Since its inception in 2003, the U.S. President’s Emergency Plan for AIDS Relief (PEPFAR) has prevented transmission of HIV to 5.5 million babies and saved an estimated 25 million lives. I find it infuriating that, under the Trump administration, this celebrated global health effort may be slowly dying. |
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| Phie Jacobs, General Assignment Reporter, Science
With contributions from Michael Price, Ana Georgescu, Hannah Richter, and Perri Thaler
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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