Distant galaxies lack dark matter, study suggests

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 […]

Colorful pinwheel puts a new spin on mouse pregnancy

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 […]

Out-of-body experiments show kids’ budding sense of self

Kids can have virtual out-of-body experiences as early as age 6. Oddly enough, the ability to inhabit a virtual avatar signals a budding sense that one’s self is located in one’s own body, researchers say. Grade-schoolers were stroked on their backs with a stick while viewing virtual versions of themselves undergoing the same touch. Just […]

Stone Age hunter-gatherers tackled their cavities with a sharp tool and tar

Stone Age dentists didn’t drill and fill cavities. They scraped and coated them. Two teeth from a person who lived in what’s now northern Italy between 13,000 and 12,740 years ago bear signs of someone having scoured and removed infected soft, inner tissue. The treated area was then covered with bitumen, a sticky, tarlike substance […]

Evidence is lacking that ‘cocooning’ prevents whooping cough in newborns

Last week, I wrote about how powerfully protective whooping cough vaccines can be when babies receive their first dose before even being born, from their pregnant mothers-to-be. As I was looking through that study, another of its findings struck me: Babies didn’t seem to get any extra whooping cough protection when their moms were vaccinated […]

Oldest evidence of patterned silk loom found in China

An ancient tomb in southern China has provided the oldest known examples, in scaled-down form, of revolutionary weaving machines called pattern looms. Four immobile models of pattern looms illuminate how weavers first produced silk textiles with repeating patterns. The cloths were traded across Eurasia via the Silk Road, Chinese archaeologists report in the April Antiquity. […]

Homo naledi may have lived at around same time as early humans

Fossils of a humanlike species with some puzzlingly ancient skeletal quirks are surprisingly young, its discoverers say. It now appears that this hominid, dubbed Homo naledi, inhabited southern Africa close to 300,000 years ago, around the dawn of Homo sapiens. H. naledi achieved worldwide acclaim in 2015 as a possibly pivotal player in the evolution […]

European fossils may belong to earliest known hominid

Europe, not Africa, might have spawned the first members of the human evolutionary family around 7 million years ago, researchers say. Tooth characteristics of a chimpanzee-sized primate that once lived in southeastern Europe suggest that the primate, known as Graecopithecus, may have been a hominid, not an ape as many researchers assume. One tooth in […]

Juno spacecraft reveals a more complex Jupiter

Jupiter’s scientific portrait is getting repainted. NASA’s Juno spacecraft swooped within about 5,000 kilometers of Jupiter’s cloud tops on August 27, 2016, giving scientists their first intimate look at the gas giant. The data are revealing surprising details about Jupiter’s gravity, powerful magnetic field and ammonia-rich weather system. The findings, which appear in two studies […]