Pregnancy changes nearly everything about an expectant mother’s life. That includes her brain. Pregnancy selectively shrinks gray matter to make a mom’s brain more responsive to her baby, and those changes last for years, scientists report online December 19 in Nature Neuroscience. “This study, coupled with others, suggests that a woman’s reproductive history can have […]

It seems logical to expect cold water to freeze faster than hot, but some experiments have suggested the opposite. There’s now a new explanation for why hot water might freeze faster than cold under certain conditions. The phenomenon, known as the Mpemba effect, may be due to the properties of the bonds that link up […]

For the third year running, Earth’s thermostat broke a new record: 2016 was the warmest year since record-keeping began in 1880. Spurred by climate change and heat from a monster El Niño, the global average surface temperature last year was 0.94 degrees Celsius (1.69 degrees Fahrenheit) higher than the 20th century average of 13.9° C […]

Just days into the Trump administration, alarm bells are ringing in the scientific community amid confusing and whiplashing reports of gag orders and funding freezes at the Environmental Protection Agency, the U.S. Department of Agriculture and other federal agencies. Various on-again, off-again directives range from putting a hold on tweeting (mostly still on) to banning […]

Generations of gurus have exhorted, “Live in the moment!” For Lonni Sue Johnson, that’s all she can do. In 2007, viral encephalitis destroyed Johnson’s hippocampus. Without that crucial brain structure, Johnson lost most of her memories of the past and can’t form new ones. She literally lives in the present. In The Perpetual Now, science […]

A prehistoric marine reptile may have given birth to its young alive. A fossil from South China may be the first evidence of live birth in the animal group Archosauromorpha, scientists report February 14 in Nature Communications. Today Archosauromorpha is represented by birds and crocodiles — which both lay eggs. Whether this fossil really is […]

A nearby ultracool star harbors seven Earth-sized planets, three with orbits that potentially put them in a habitable zone. That makes the system, around a star called TRAPPIST-1, a prime target in the search for signs of alien life. Its discovery also hints that many more cousins of Earth may be out there than astronomers […]

The true nature of the “Tully monster” may once again be a mystery. Just last year, some researchers declared that the extinct aquatic animal was a vertebrate, possibly a relative of today’s lampreys. Not so fast, says vertebrate paleontologist Lauren Sallan. Like a mismatched puzzle, the Tully monster lacks some vertebrate pieces and has others […]

Very distant galaxies have surprisingly little dark matter, the invisible stuff thought to make up the bulk of matter in the universe, new observations suggest. Stars in the outer regions of some far-off galaxies move more slowly than stars closer to the center, indicating a lack of dark matter, astronomer Reinhard Genzel and colleagues report […]

This rainbow pinwheel of mouse placentas isn’t just an eye-catching, award-winning image. The differences in color also provide researchers with new clues to how a mother’s immune system may affect her or her baby’s health during pregnancy. The work could lead to earlier diagnosis and treatment of preeclampsia, a common pregnancy complication. Suchita Nadkarni, an […]