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Why do beaches today have seashells from clams and snails instead of brachiopods。 A new study suggests the answer lies in Earth's greatest mass extinction, when warming oceans and falling oxygen levels wiped out animals that couldn't adapt。 Species with body plans and metabolisms better suited to the changing conditions survived and went on to domi
A major DNA study has rewritten the koala's evolutionary story, revealing that the species suffered a dramatic population collapse about 100,000 years ago, long before humans arrived in Australia。 By calculating the koala's mutation rate for the first time and analyzing hundreds of genomes, researchers discovered that every living koala traces back
Researchers have achieved a major milestone by creating a long-sought two-dimensional quantum material and confirming its unusual conducting edge states。 The ability to control these states through strain could make the material a promising platform for future room-temperature quantum electronics
A distant Sun-like star appears to have devoured one of its planets, leaving behind a surprising chemical fingerprint。 Researchers found an unusually high concentration of lithium, a strong sign that planetary material was mixed into the star。 Careful comparisons with dozens of similar stars confirmed the signal is highly unusual, and scientists th
Researchers have created self-destructing living plastic that uses engineered bacteria to completely break itself down when activated。 The material degrades in just six days without creating microplastics, offering a potential new solution for single-use plastic waste
The asteroid that wiped out the dinosaurs was likely an exceptionally rare CO chondrite from a distant region of the solar system。 Its unusual chemistry suggests that planet-cooling dust and debris, rather than sulfur inside the asteroid, may have delivered the deadliest blow
A new particle detector called PLATON could replace millions of tiny detector components with a single block of light-producing material。 Using a light-field camera, highly sensitive photon sensors, and AI, it reconstructs particle paths in fast, detailed 3D。 Simulations suggest it could match or surpass today’s best detectors while being far easie
NASA has chosen 41 commercial technology projects that could solve critical challenges for future missions to the Moon and Mars。 From powering lunar outposts to protecting spacecraft from Moon dust, the innovations are designed to push both space exploration and the commercial space economy forward
A team of mathematicians used whimsical "silly sprinklers" to solve a physics mystery that has puzzled scientists for decades。 Their experiments showed that the rotation of both normal and reverse sprinklers is driven by the momentum of flowing water, not by the outside water flow or other long-standing theories。 The results finally provide a clear
A new review highlights exciting progress in atomically thin quantum materials where light and magnetism work together in ways never before possible。 In these materials, light-generated excitons can interact directly with magnetic behavior, creating opportunities to control magnetic states using light alone。 Scientists believe this could pave the w
A new quantum theory bridges two rival models of how impurities behave inside many-particle systems, resolving a problem that has challenged physicists for decades。 The findings could reshape experiments on ultracold atoms, semiconductors, and other exotic forms of quantum matter
The government is piloting a program that uses AI for insurance-coverage decisions
A planet with one side permanently roasting and the other frozen in endless darkness might still have a chance of supporting life。 Researchers found that heat inside a tidally locked exoplanet could circulate in a stable, continuous loop, helping moderate temperatures in certain regions。 Their laboratory model suggests these worlds may be more hosp
Scientists at Nanyang Technological University in Singapore have discovered a surprisingly simple way to create exotic light structures called optical skyrmions using a 200-year-old optical effect known as the Poisson spot。 Instead of relying on expensive, highly engineered materials, they simply shine a laser at a tiny circular disc, producing sta
Scientists have identified new clues that could help astronomers spot one of the most famous hypothetical alien megastructures: a Dyson sphere。 The study finds that red dwarfs and white dwarfs are the most promising stars to examine, since advanced civilizations could potentially build energy-harvesting swarms around them more easily。 These objects
NASA's Perseverance rover has reached an impressive new milestone on Mars, completing the equivalent of a full marathon by driving 26。2 miles (42。195 kilometers) across the Red Planet
NASA's James Webb Space Telescope has revealed new details about the blistering lava planet 55 Cancri e, where temperatures are high enough to melt rock。 The data indicate the planet likely has a hydrogen-rich atmosphere shaped by gases escaping from its molten interior, with signs that volcanic outgassing may even create temporary clouds