Innehållsförteckning för November/December 2025 från Discover

VULTURE POPULATIONS have dwindled across Europe, Asia, and Africa, prompting concerns about a similar decline in the populations of vultures in North and South America. But could the loss of these scavengers have the same devastating impacts for human health in the Americas as it has had in India in the past? Recent research suggests that it could. In May 2025, a study published in Ecology and Evolution showed that declining vulture populations could contribute to public health crises in North and South America, too, unleashing deadly diseases on animals and humans alike. “This research underlines the unique and irreplaceable role that vultures play as nature’s ‘clean-up crew,’” said Julia Grootaers, a study author and a behavioral ecologist at the University of Exeter, Cornwall, in a statement. “Unloved and unappreciated…

ONE WOULD think that the astronauts’ living spaces should be perfectly clean, but it turns out that creating a “dirtier” environment with more microorganisms from Earth may boost their health. That’s what recent research in Cell seems to suggest, anyway, after showing that the International Space Station (ISS) is overly sterile. While this may not sound like an issue, the February 2025 study suggests that the cleanliness could carry some surprising consequences: The sterile nature of the station has led to a low diversity of microbes, which could be contributing to immune dysfunction, skin irritation, and other inflammatory conditions in astronauts. According to the study authors, the results indicate that the most common health problems observed in space could be mitigated by introducing certain environmental microorganisms from Earth onto the…

A FISH, A COCONUT, a ruler, a turtle, a mango, a gecko, and even a dead frog — these are just some of the odd things that frogs have been recorded trying to have sex with. Frog sex, in most species, involves the male gripping onto the female from behind for long periods of time — from hours to days — until they’ve succeeded in fertilizing their eggs. But mating can be very competitive for these amphibians, causing some males to try to copulate with things that can’t actually give them offspring. Scientists have observed this phenomenon, called misdirected amplexus, in frogs for over a century, and are continuing to dig into its prevalence, its origin, and its connection to the climate. While their work is still far from finished,…

We’ve heard it said that time is an arrow, always moving in one direction at a uniform rate. But the field of physics is constantly challenging our understanding of time’s true nature, helped over the years by the ideas, theories, and questions of some of the greatest minds in science, philosophy, and even fantasy. Is time actually real, or just a trick of our perception? Will time travel ever be possible, and if so, what would that experience be like? Does time have a beginning or an eventual end? While there may be no definitive answers to these and other temporal deliberations, that hasn’t stopped scientists and theorists from devoting their attention — and their time — to the subject. WHY DO HUMANS PERCEIVE TIME THE WAY WE DO? Physics…

It’s not unusual for small children to have big dreams. Some might imagine themselves doing great things when they grow up, such as climbing the world’s highest mountain, becoming an astronaut, or winning an Olympic gold medal. When he was a middle school student around the start of this century, Gašper Beguš had his own lofty vision: He wanted to learn the hardest “dead” (or extinct) language ever invented. While that might seem like a strange goal for a preteen to set for himself, it did not come completely out of the blue. Beguš’s mother was a linguist, so young Gašper had seen plenty of archaic texts lying around the house, filled with secrets that he hoped, someday, to uncover. He also came from Slovenia — a small nation whose…

I magine a seasoned scientist hitting “send” on an article meant for the general public — a breakdown of groundbreaking new research, simplified for everyday readers. He’s confident. After all, he’s published dozens of peer-reviewed papers, landed features in prestigious journals, and led a well-funded lab for decades. How hard can it be to write for non-scientists? Pretty hard, it turns out. When the editor opens the piece, she’s baffled. There’s no clear introduction to ease readers in, just a jumble of jargon and dense explanations. Where’s the hook? The human angle? Why does it read like a textbook in a foreign language, and a dry one at that? Here’s the twist: Believing that you’re good at something doesn’t automatically make you good at it. In fact, people who know the…

Feather Light SHINE AN ULTRAVIOLET light on one of the finest specimens of the first fossil bird, and its feathers will appear in an aura of iridescent blue. In May 2025, a team of researchers published this photo of the Chicago Field Museum’s Archaeopteryx — a 150-million-year-old fossil from the Jurassic Period — in a paper in Nature. Creating contrast between the fossilized tissue and the surrounding sediment, the UV light allowed the team to spot a new set of feathers that might have helped Archaeopteryx fly. Similar to the tertial feathers seen on modern birds, this long, lightweight fringe lined Archaeopteryx’s upper arms and likely improved its ability to generate lift for flight. According to the researchers, the image may reveal why Archaeopteryx took to the skies while its…

HUMANS HAVE around 20,000 protein-coding genes, which serve as blueprints for the protein molecules that shape and power our cells. But little is known about how those protein molecules organize and interact, says Trey Ideker, a professor of medicine at the University of California San Diego. Without that knowledge, trying to study and treat disease is “like trying to understand how to fix your car without the shop manual.” In an April 2025 study in Nature, Ideker and his team presented their latest attempt to fill this information gap: a map of a human cell, showing the locations of more than 5,000 proteins, organized into smaller and smaller structures. The map goes far beyond the simplified diagrams you may recall from high school biology class. While familiar features like the…

THE NEXT TIME YOU chomp on a popsicle, then flinch from a bolt of pain, you’ll have something to blame: a 465-million-year-old fish. That’s because researchers have determined that dentine — a substance that’s found in the teeth of modern humans and the armor of ancient fish — serves a similar sensory purpose in the former as it did in the latter. Reported in a study in Nature in May 2025, the results support the theory that humans inherited their teeth (and their tooth sensitivity) from the exoskeletons of the earliest vertebrates. PALEONTOLOGISTS have long theorized about the evolutionary ties between human teeth and fish exoskeletons, and now, thanks to the new study, they’ve pinpointed their shared purpose as sensory organs. But the study authors hadn’t set out to find…

SIT COMFORTABLY and pay attention to your breath as you inhale and exhale. When thoughts drift into your mind, just ignore them and stay focused on your breath. Seems simple enough, right? But it turns out that this basic breathing practice, known as mindfulness meditation, is powerful stuff. Not only does it help reduce stress and improve mood, but it actually changes the structure and activity of your brain. And those changes can be quite beneficial. SARA LAZAR is a neuroscientist at the Massachusetts General Research Institute at Harvard University who studies meditation’s effects on the brain. These effects, she says, are seen primarily in three brain regions: the posterior cingulate cortex, the hippocampus, and the amygdala. The posterior cingulate cortex, or the PCC, is involved in mind wandering and…

“SOUND HAS POWER!” The audiologist Deanna Meinke holds a tuning fork in one hand and a Ping-Pong ball on a string in the other. Her demonstration is well rehearsed: A professor at the University of Northern Colorado, Meinke is also the co-director of Dangerous Decibels, a nationwide initiative encouraging kids to safeguard their hearing. Meinke strikes the tuning fork against a desk and raises it to the Ping-Pong ball, which springs away, falls back, and springs away again, dancing spastically until the fork’s hum fades. When she makes her declaration, her voice lingers on the word “power” as if casting a spell. Sounds are essentially waves of energy that trigger cascades of molecular collisions. These waves can certainly be powerful — damaging our inner ears and causing hearing loss. This…

VULTURES OFTEN get a bad rap, but they keep their environments clean. You can think of these birds as nature’s garbage collectors — devouring carcasses and other animal material, mopping up potentially harmful pathogens in the process. The problem is that populations of vultures and other apex scavengers are declining worldwide. In fact, over a third of global scavenger populations are at risk. And according to the authors of a June 2025 study in the Proceedings of the National Academy of Sciences, this is not just a disaster for biodiversity — it could also spell trouble for human health, as animals like vultures and hyenas have historically curbed cases of rabies, anthrax, and other zoonotic diseases in humans. “There is this prejudice that these scavengers — vultures and hyenas and…

ARCHAEOLOGISTS IN Sweden have taken an interdisciplinary approach to tell the story of what it was like to live with a disability in the Middle Ages. Reporting their results in a study in Open Archaeology in April 2025, the researchers analyzed the skeleton of a man in his 30s with a severe knee injury. By combining textual analysis with osteological and archaeological methods, the team put together a nuanced picture of the medical and cultural treatment of medieval disabled people. “Deducing social norms regarding physical impairment and disability from religious and legal texts is difficult because it presents an idealized perspective,” said Blair Nolan, a study author and a Ph.D. student at Lund University, in a statement. “We can enrich our understanding of disability and identity through detailed osteological and archaeological…

SOLAR PARTICLE STORMS bombard Earth on occasion, messing with our communications systems and satellites. But the majority of these phenomena pale in comparison to the strongest solar particle storm on record — an event that inundated the planet with particles from the Sun around 14,300 years ago. An April 2025 study in Earth and Planetary Science Letters has shed light on this extreme event, which battered Earth in 12350 B.C.E. One of the handful of severe solar particle storms that have occurred throughout history (and the only such storm that has been recorded from before the ongoing Holocene epoch), the event raises the stakes for the future, spelling trouble for humans if history happens to repeat itself. FROM TIME TO TIME, the Sun launches a blast of charged particles into…

FOR SARAH MURPHY, a proclivity toward sleepiness appears to predate even her birth. Due to a lack of movement in the womb, her mother, Marie Murphy, required extra heartbeat checks at the doctor’s office to make sure her unborn baby was still alive. Then after birth, Sarah took to sleeping through the night right away, much to the envy of other parents in Marie’s circle who were used to multiple overnight wakings from their babies. Later on, Sarah, now in her 20s, remembers drifting off while reading books to herself as a child or being awakened by frustrated teachers in grade school when she fell asleep at her desk. Still, the sleepiness didn’t seem that extreme, especially since Sarah had many periods of normal energy and could get through most…

Though no one knows whether time travel is physically possible (and it probably isn’t), we do know that Einstein’s theory of general relativity proves the concept is at least theoretically sound. Specifically, his equations allow for closed timelike curves, or CTCs: loops in space-time that end where they begin. An object following one of these circular trajectories would eventually arrive back at the place (and time) it started, and could interact with its past self. Of course, there’s no guarantee that they actually exist. Many eminent physicists have argued against the possibility of CTCs, whether naturally occurring or engineered via time machines made by intelligent beings. “The laws of physics do not allow the appearance of closed timelike curves,” the late physicist Stephen Hawking wrote matter-offactly in 1992. He half-jokingly…

Before cars offered so many technological luxuries, a map from the glove compartment was a driver’s best friend. Now, navigation apps have rendered map reading an ancient art — and GPS has taken the helm. Discover envisioned its omnipresent reach in the December 1999 feature “No Place to Hide”, back when one of the first mobile phones with integrated GPS had just hit the market, the Benefon ESC! The Global Positioning System was first established by the U.S. Department of Defense (DoD) in 1973, originally devised to improve military navigation. The project took its first leap when its maiden satellite, Navstar I, was launched into space in 1978. Plans to make GPS available for civilian use took shape in the 1980s, with handheld GPS receivers debuting near the end of…