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Dinosaurs conquered the land at enormous sizes, but strangely, they almost never evolved into truly tiny animals。 New research suggests that physiology alone can’t explain this missing miniature end of the dinosaur spectrum—and that early mammals may have been partly responsible。 While dinosaurs kept mammals from becoming large, small mammals may h
Deep underground, bacteria may be capable of doing something remarkable: trapping toxic uranium before it spreads。 When researchers fed microbes in uranium-contaminated mine water with glycerol, about 95% of the dissolved uranium disappeared within 130 days。 The bacteria helped convert it into an unusually stable uranium compound that had rarely be
Genetic changes may set off a chain reaction that causes the spine’s natural shock absorbers to harden and deteriorate。 Zebrafish with a faulty collagen-related gene developed mineral buildup and spinal fusion similar to human disc disease。 Researchers were able to reduce the damage using an existing osteoporosis drug and by targeting fat metabolis
More than 60,000 years ago, humans in southern Africa were engraving ostrich eggshells with intricate geometric patterns that appear far more organized than previously realized。 Researchers found recurring grids, parallel lines, right angles, and repeated shapes, suggesting the designs followed deliberate rules rather than being improvised。 The eng
Stress may literally scramble the brain’s internal GPS。 Researchers found that cortisol, a hormone released during stress, made people significantly worse at navigating a virtual environment and disrupted the precise activity of grid cells, specialized brain cells that help us understand where we are in space。 When landmarks were missing, this navi
Teens who start using cannabis may experience slower growth in memory, attention, language, and processing speed。 Their abilities often developed normally at first, then began leveling off while nonusers continued improving。 THC appeared to be the most likely driver, especially for worsening memory
Metal-rich asteroids could one day become hardware stores for Mars, supplying the materials needed to build and repair a growing colony。 A new analysis shows that carefully selected asteroids may be reachable with current spacecraft technology。 Some could even provide the ingredients for making rocket fuel in space, dramatically reducing the burden
A ten-month Antarctic experiment found that astronauts may struggle not only with loneliness but also with spending too much time around the same people。 Frequent contact was linked to greater tension and mistrust, while the crew increasingly divided into cultural and language-based groups
Scientists have discovered incredibly tiny plasma whirlpools swirling across the Sun’s surface, some just 20 kilometers wide。 These previously invisible vortices may twist magnetic fields and help build up the energy released in small solar eruptions called nanoflares。 They may also help magnetic fields spread through the Sun’s atmosphere far faste