2021 was the year the COVID-19 vaccines had to prove their mettle. We started the year full of hope: With vaccines in hand in record-breaking time and their rollout ramping up, we’d get shots in arms, curb this pandemic and get life back to normal. That was too optimistic. Roughly 200 million people in the […]

Brains are like sponges, slurping up new information. But sponges may also be a little bit like brains. Sponges, which are humans’ very distant evolutionary relatives, don’t have nervous systems. But a detailed analysis of sponge cells turns up what might just be an echo of our own brains: cells called neuroids that crawl around […]

In a remote corner of Brazil’s Amazon rainforest, researchers have spent decades catching and measuring birds in a large swath of forest unmarred by roads or deforestation. An exemplar of the Amazon’s dazzling diversity, the experimental plot was to act as a baseline that would reveal how habitat fragmentation, from logging or roads, can hollow […]

Regenerating body parts is never easy. For instance, some lizards can grow back their tails, but these new appendages are pale imitations of the original. Now, genetically modified stem cells are helping geckos grow back better tails. Tweaking and implanting embryonic stem cells on the tail stumps of mourning geckos (Lepidodactylus lugubris) allowed the reptiles […]

Mystery mummies from Central Asia have a surprising ancestry. These people, who displayed facial characteristics suggesting a European heritage, belonged to a local population with ancient Asian roots, a new study finds. Until now, researchers had pegged the mummified Bronze Age bunch as newcomers and debated about where in West Asia they originally came from. […]

Concerns abound about what’s gone wrong in modern societies. Many scholars explain growing gaps between the haves and the have-nots as partly a by-product of living in dense, urban populations. The bigger the crowd, from this perspective, the more we need power brokers to run the show. Societies have scaled up for thousands of years, […]

he James Webb Space Telescope has been a long time coming. When it launches later this year, the observatory will be the largest and most complex telescope ever sent into orbit. Scientists have been drafting and redrafting their dreams and plans for this unique tool since 1989. The mission was originally scheduled to launch between […]

Squabbling sibling planets may have hurled space rocks when they were young. Simulations suggest that space rocks the size of baby planets struck both the newborn Earth and Venus, but many of the rocks that only grazed Earth went on to hit — and stick — to Venus. That difference in early impacts could help […]

Fleets of private satellites orbiting Earth will be visible to the naked eye in the next few years, sometimes all night long. Companies like SpaceX and Amazon have launched hundreds of satellites into low orbits since 2019, with plans to launch thousands more in the works — a trend that’s alarming astronomers. The goal of […]

A meandering trek taken by light from a remote supernova in the constellation Cetus may help researchers pin down how fast the universe expands — in another couple of decades. About 10 billion years ago, a star exploded in a far-off galaxy named MRG-M0138. Some of the light from that explosion later encountered a gravitational […]