Best Citation Awards

To put one of physicists’ most important theories to the test, scientists go to extremes. Extremely strong electromagnetic fields, that is. The theory of quantum electrodynamics, which describes interactions of electrically charged particles and light, has been  checked to painstaking precision  ( SN: 2/23/23 ). The theory correctly predicts properties of simple atoms, like hydrogen or helium. But it’s less carefully tested under intense electromagnetic fields, like those that exist around large atomic nuclei.  The theory’s  predictions hold up  even in those conditions, physicist Robert Lötzsch and colleagues report in the Jan. 25  Nature . Quantum electrodynamics, or QED, looms large in physics. It’s an integral part of the standard model of particle physics, the theory of fundamental particles and their interactions. So testing it in all possible scenarios is key. To probe QED’s prowess, Lötzsch and colleagues turned to uranium, which has a whopping 92 protons in its nucleus. Th

Krystal Tsosie grew up playing in the wide expanse of the Navajo Nation, scrambling up sandstone rocks and hiking in canyons in Northern Arizona. But after her father started working as a power plant operator at the Phoenix Indian Medical Center, the family moved to the city. “That upbringing in a lower socioeconomic household in West Phoenix really made me think about what it meant to be a good advocate for my people and my community,” says Tsosie, who like other Navajo people refers to herself as Diné. Today, she’s a geneticist-bioethicist at Arizona State University in Tempe. The challenges of urban life for Tsosie’s family and others, plus the distance from the Navajo Nation, helped spark the deep sense of community responsibility that has become the foundation of her work. Krystal Tsosie is pictured here on Easter on the Navajo Reservation in Leupp, Ariz. Courtesy of Elloise Tsosie Tsosie was interested in science from an early age, volunteering at the Phoenix Indian Medic

The pandemic may no longer be a public health emergency, but plenty of my neighbors, friends and family are still having bouts and brushes with COVID-19. Just this past summer, a relative got COVID-19 on a camping trip. One of my neighbors was sick. Another had no symptoms but kept his distance while a bright pink line appeared on his test strip each morning. He shouted updates across the street as we walked our dogs: “The line was a little fainter today.” “It’s gone.” And finally, “It’s been two days since the line disappeared.” We and the dogs rejoiced at the reunion. In the fall and winter, the reports poured in again: coworkers stricken with the coronavirus; the sick neighbor’s family got COVID-19 in the fall long after he recovered; a friend got sick after visiting a relative and missed Christmas with her parents; another friend’s cousins tested positive just after spending the holidays together. The experiences of the people in my circle mirror the peaks and valleys of contagi

Bruce the kea is missing his upper beak, giving the olive green parrot a look of perpetual surprise. But scientists are the astonished ones. The typical kea ( Nestor notabilis ) sports a long, sharp beak, perfect for digging insects out of rotten logs or ripping roots from the ground in New Zealand’s alpine forests. Bruce has been missing the upper part of his beak since at least 2012, when he was rescued as a fledgling and sent to live at the Willowbank Wildlife Reserve in Christchurch. The defect prevents Bruce from foraging on his own. Keeping his feathers clean should also be an impossible task. In 2021, when comparative psychologist Amalia Bastos arrived at the reserve with colleagues to study keas, the zookeepers reported something odd: Bruce had seemingly figured out how to use small stones to preen. “We were like, ‘Well that’s weird,’ ” says Bastos, of Johns Hopkins University. Over nine days, the team kept a close eye on Bruce, quickly taking videos if he started cleaning

As I step among poop-covered rocks toward the plateau of a small island in the Galápagos, a part of me rejoices. Not only am I about to see the archipelago’s famed blue-footed boobies for the first time, but the sight of guano everywhere, and birds to make fresh batches, serves as a reminder: The ongoing avian influenza outbreak has not yet ravaged this picturesque place. Ghostly, leafless Palo Santo trees and saltbushes sprinkle the island, surrounded by boulders in varying shades of red-tinged black and brown. White splotches of guano splattered on rocks are hard to miss against this arid landscape on North Seymour Island in November, the tail end of the dry season. The poop’s sources are similarly difficult to overlook. The island is known for hosting a large colony of magnificent frigatebirds ( Fregata magnificens ), some of which hang suspended in the air above tourists’ heads as we disembark from a dinghy and scramble up the rocky path. As I admire the birds’ fabulous red throa

Physicists are fascinated with heady puzzles, from the nature of space and time to how the universe came to be. But spinning lawn sprinklers? Yes, that too. A new experiment provides an answer to a quirky physics quandary popularized by physicist Richard Feynman in the 1980s. The puzzle centers on a style of sprinkler that works by squirting water out the ends of an S-shaped tube. The sprinkler spins away from the escaping water due to conservation of angular momentum. That much is straightforward. But what happens if you stick the sprinkler in a tank of water and have it suck the water in? The question seems simple. But complex fluid flows and subtleties of momentum conservation have led different physicists to argue that it should either spin in the opposite direction as it does when operated normally, or not move at all. Different experiments likewise clashed. So applied mathematician Leif Ristroph and colleagues gave it a whirl. “It ended up being one of the hardest problems our

Honeybees rely on plant pollen as a protein-packed food source. And some are even willing to steal from other bees to get it. Pollen stealing has been seen before, in the United States. But now, researchers in Italy have also observed honeybees snatching pollen off the backs of bumblebees . The observations, published December 21 in Apidologie , are among the most extensive documentation of bee-on-bee larceny to date. On a summer trip in 2019 to Mount Antola, in the northern Italian region of Liguria, independent naturalists Tiziano Londei and Giuliana Marzi, both based in Milan, recorded video of what they thought were honeybees ( Apis mellifera ) trying to push bumblebees off the flower of a woolly thistle ( Cirsium eriophorum ). A closer look at the video, however, revealed that this wasn’t a case of competitive harassment — it was a full-blown robbery.   A thieving honeybee ( Apis mellifera ) snags pollen off the body of a red-tailed bumblebee ( Bombus lapidarius ). Because ho

The oddball minority of animals that don’t lay eggs includes a tough little snail called a rough periwinkle. Unlike mammals giving birth to kittens and fawns and helpless little humans, this tidal-zone snail has switched to live birth relatively recently. Its newcomer version of birthing offspring into the world without an eggshell is…. different: These periwinkle moms give birth multiple times a day. And unlike humans, it’s probably not the mom but the babies who do the hard labor. Egg-laying periwinkle relatives have a jelly gland that creates a goo-protected mass of eggs outside the mom’s body. But in Littorina saxatilis , the gland has evolved into a make-do womb, or brood pouch . Eggs still form there, but stay inside mom’s body until after they hatch, says evolutionary ecologist Kerstin Johannesson of the University of Gothenburg in Sweden. Mom can have up to a few hundred embryos at various stages of maturation in the gland. When birthing the mature ones, “if she starts to p

The largest shark discovered to date — the monstrous Otodus megalodon — may have been a sleek, long-bodied leviathan. A fresh look at the extinct predator’s fossilized remains suggests its body was many meters longer and possibly more slender than previous reconstructions , researchers report January 22 in Palaeontologia Electronica . The findings may offer better insights into the biology and lifestyle of megalodon, including how fast it swam or what it ate ( SN: 6/27/23 ).  Reconstructing what ancient, extinct animals looked like when they were alive is challenging, even when complete fossilized remains are available. But reconstructing megalodon is much harder. Like all sharks, the giant had a cartilaginous skeleton that preserves poorly relative to bone. It is mostly known from teeth and many meters of fossilized, cartilaginous vertebrae, with the rest of the skeleton remaining a mystery. Traditionally, modern great white sharks ( Carcharodon carcharias ) have been used as a m

Happy leap second! — Science News , January 12, 1974 A “leap second” has been invented … to keep time signals used by navigators in step with the actual motion of the Earth. The latest leap second was celebrated New Year’s Eve at the stroke of midnight Greenwich Mean Time, when around the world … radio stations added an extra “beep” to their hourly time signals. Update Time is running out for the leap second. In 2022, metrologists voted to abandon the timekeeping quirk by 2035. Unlike the leap year, which occurs every four years, the leap second is deployed whenever clocks need adjusting due to variations in Earth’s spin causing slight changes in the length of a day. Global officials have inserted a leap second 27 times since 1972. But satellites and other tech that rely on the precise time kept by atomic clocks can glitch when the clocks are adjusted ( SN: 4/22/06, p. 248 ). Scientists have suggested using a leap minute instead, which would require atomic clocks be reset onc

Swallow the wrong microbe, and you might end up in the hospital with a needle or two in your arm — and plenty of itty-bitty bacterial needles poking at you from the inside. That’s because many bacteria that make us sick use microscopic, syringelike structures to inject our cells with proteins that wreak havoc from the inside. Now, researchers have shown how these microbes load their nanoscale needles with proteins. Tracking individual proteins as they jittered around inside living bacteria revealed the microbes use a shuttle bus–like system to load their syringes: shuttle proteins travel random paths within the microbes’ interiors , grabbing cargo destined for injection as they go and dropping it off at the syringes, scientists report January 3 in Nature Microbiology . Knowing how these bacterial needles work could help scientists learn how to disrupt them — or commandeer them for medical applications, like using bacterial needles to inject cancer cells with targeted drugs while leav