Math puzzle: A Loopy Holiday Gift Exchange
Solve the math puzzle from our December 2025 issue, in which a holiday gift exchange occurs.
Headlines
- All
- Africa
- Asia
- Business
- Culture
- Environment
- Europe
- Gaming
- Markets
- Middle East
- Movies & TV
- Music
- Politics
- Science
- South America
- Tech
- World News
Here’s how Rudolph’s light-up nose might be possible
Simple chemistry could give the reindeer his famously bright snout. But physics would make it look different colors from the ground.
The world's new US$125 billion rainforest trust fund revives a 1990s idea—and shows its limits
A US$125 billion rainforest fund is being hailed as a flagship announcement from the 2025 UN climate summit in Belém, Brazil. The goal is noble: this is essentially a trust fund that will pay countries to keep their tropical forests standing. But its core idea was tried 30
Here's what Black Friday sales shopping does to your brain
Every November, Black Friday arrives with big claims of massive savings and "one-day-only" deals. We are bombarded with offers that seem too good to pass up. But beneath all this lies something far more strategic.
Victoria will force home sellers to reveal their reserve price: Will other states follow?
If you've ever tried to buy a home at auction, you know how frustrating it can be to show up thinking you can afford a particular property, only for it to sell for far more than the advertised price.
Mirror symmetry prompts ultralow magnetic damping in 2D van der Waals ferromagnets
Two-dimensional (2D) van der Waals (vdW) ferromagnets are thin and magnetic materials in which molecules or layers are held together by weak attractive forces known as vdW forces. These materials have proved to be promising for the development of spintronic devices, systems
With two launches in the books, Blue Origin announces even more powerful New Glenn is coming
Blue Origin's New Glenn rocket is powerful, but Jeff Bezos' rocket company wants more.
How Home Depot's newest AI tool could give it an edge with pro contractors
Home Depot is leveraging artificial intelligence to help professional contractors with a complex task—measuring and quantifying all the materials needed for residential projects.
California regulators approve rules to curb methane leaks and prevent fires at landfills
In one of the most important state environmental decisions this year, California air regulators adopted new rules designed to reduce methane leaks and better respond to disastrous underground fires at landfills statewide.
Psychiatrist explains how to talk politics during the holidays
Politics can be a stressful discussion topic, but when the holiday season arrives, political chatter is difficult to avoid, especially in a world that feels polarized and divided. A Baylor College of Medicine psychiatrist explains how to discuss politics in a calm manner among
Q&A: How will recent economic disruptions impact the holiday shopping season?
November marks the start of the busiest time of year for retailers and shoppers alike. But how will recent developments like tariffs and the government shutdown impact the winter shopping season?
Study finds Indigenous-led hunting most effective for tackling deer overabundance on B.C. islands
As ecosystems in coastal British Columbia disappear due to long-term browsing pressures from overabundant black-tailed deer, a new study led by UBC with Coast Salish Nations and regional research partners identifies the most effective solutions to address deer overabundance on
Japan's eel delicacy faces global conservation pressure
At an eel restaurant near Tokyo, four friends sit down to eat a Japanese delicacy now the subject of a heated international debate as its numbers decline.
Fossil fuel showdown looms on UN climate summit's final day
A breach, a blockade, and a blaze: tumultuous UN climate talks head into their final day Friday in the Brazilian Amazon, with countries still sharply split over fossil fuels.
A drying-up Rio Grande basin threatens water security on both sides of the border
One of North America's longest rivers, the Rio Grande—or Rio Bravo as it's called in Mexico—has a history as deep as it is long. Indigenous people have tapped it for countless generations, and it was a key artery for Spanish conquistadors centuries ago.
Plant breeding discovery could pave way for new crop species
One of the great mysteries in plant biology is how, given the clouds of pollen released by dozens of plant species all at the same time, an individual plant can recognize which particular species' pollen grains will induce fertility and which to reject. We are now one step
Mapping the unseen: How Europe is fighting back against invisible soil pollution
Across Europe, scientists and citizens are uncovering a hidden legacy of contamination beneath their feet. From Denmark's first PFAS crisis to a new generation of soil-mapping initiatives, a continent is learning to see—and stop—the pollution it once ignored
Tiny microneedle patch dramatically improves heart attack recovery
Researchers created a dissolvable microneedle patch that delivers IL-4 directly to damaged heart tissue, jump-starting repair after a heart attack. The targeted approach shifts immune cells into a healing mode while improving communication between heart muscle and blood vessel
New research uncovers hidden divide in West Coast killer whales
Scientists confirmed that West Coast transient killer whales actually form two separate groups split between inner and outer coastal habitats. Inner-coast whales hunt smaller prey in shallow, maze-like waterways, while outer-coast orcas pursue large marine mammals in deep
Scientists warn heatwaves will intensify for 1,000 years even after net zero
New climate modeling shows that heatwaves will keep getting hotter, longer, and more frequent for centuries—even after the world hits net-zero emissions. Delays of just a few years dramatically increase the likelihood of extreme, once-rare heat disasters, especially for
Elites wield huge influence over deepening polarization—now we can tell exactly how much
Political systems become polarized when internal unity within groups strengthens and the divide between them deepens. As polarization intensifies, societal tensions can grow, making it difficult to find compromises. The intensity of polarization has been measured in research,
Is social media subjecting Black women to radicalized digital policing?
Influencers use oppression, manipulation and weaponization to police Black women on social media, according to new research uncovering the entrenched nature of digital racism.
Ancient retrovirus structure reveals link to modern respiratory viruses
Retroviruses are viruses that have evolved the ability to write their genetic code into a cell's own DNA. The most ancient known lineage of retroviruses, foamy viruses, emerged around 450 million years ago, before animal life moved onto land or even the evolution of trees.
“Living Fossil” Discovered by Accident Could Reshape Tree of Life
Meet the miniscule protist harboring jaw-dropping evolutionary secrets The post “Living Fossil” Discovered by Accident Could Reshape Tree of Life appeared first on Nautilus .
Can theater performance skills help teachers in the classroom?
Most people can recall a favorite class or teacher who left an indelible mark on their lives. While subject matter plays a role, the deeper connection often stems from how that teacher made students feel.
How children learn to be good
Richard Weissbourd and Kiran Bhai are part of the leadership team at Making Caring Common, a Harvard Ed School initiative focused on making moral and social development a priority in child-raising. In this article, they answer this question:
Cloth diapers can inspire a feelgood factor that is the secret of long-term behavior change
During the first COVID-19 lockdown, we were both mothers trying to stay sane. Our chats often revolved around diapers, feeding, sleep deprivation and motherhood chaos. Between laughter and exhaustion, cloth diapers kept coming up in conversation.
New collection of bacteria-eating viruses to tackle hospital superbug
Potential treatments for one of the world's most dangerous hospital superbugs have been found in a surprising location—hospital toilets.
Lions Have Been Keeping One of Their Roars Secret
Scientists identify a new call issued by the King of the Jungle The post Lions Have Been Keeping One of Their Roars Secret appeared first on Nautilus .
840 million women: The rate of violence against women has barely changed in 25 years
Violence against women remains one of the world's most persistent and under-addressed human rights crises, with very little progress in two decades, according to a landmark report released today by the World Health Organization (WHO) and UN partners.
A new type of lion roar could help protect the iconic big cats
A new study has found African lions produce not one, but two distinct types of roars—a discovery set to transform wildlife monitoring and conservation efforts.
Lions have a second roar that no one noticed until now
A machine learning analysis of wild lion audio reveals they have two roar types, not one. This insight might help detect where lions are declining.
Mindfulness could help strengthen relationships
Life can put strain on any couple's relationship. But mindfulness could help keep it strong, according to a recent study from the University of Georgia published in Child & Family Social Work.
Mystery of how turtles read their magnetic map solved—they feel the magnetism
Loggerhead turtles are able to sense Earth's magnetic field in two ways, but it wasn't clear which sense the animals use to detect the magnetic field when navigating using the magnetic map they are born with. Now researchers from the University of North Carolina at Chapel Hill
This Ancient Sea Monster Had a Killer Bite and No Teeth
The Dunkleosteus was even weirder than we thought The post This Ancient Sea Monster Had a Killer Bite and No Teeth appeared first on Nautilus .
Want to make new friends? Take a lesson from these birds
Making new friends has its challenges, even for birds. Researchers at the University of Cincinnati found that monk parakeets introduced to new birds will "test the waters" with potential friends to avoid increasingly dangerous close encounters that could lead to injury. They
Quantum calculations expose hidden chemistry of ice
When ultraviolet light hits ice—whether in Earth's polar regions or on distant planets—it triggers a cascade of chemical reactions that have puzzled scientists for decades.
Q&A: Euclid mission's quest to reveal hidden patterns of cosmic evolution
The European Space Agency's Euclid mission—designed to map the geometry of the dark universe with unprecedented precision—continues to deliver its first scientific insights. The Euclid Consortium has published a fresh set of seven scientific papers based on data from the Euclid
All flow directions scheme can boost weather forecast accuracy in complex terrain
Imagine trying to predict wind patterns as air flows across a landscape. It's a straightforward task over a flat plain—but becomes more complex when the terrain shifts to jagged mountain ranges. Here, wind does not simply sweep over peaks; it is deflected, slowed, and forced
Light-controlled embryos reveal power of mechanical forces in human development
Only two weeks after fertilization, the first sign of the formation of the three axes of the human body (head/tail, ventral/dorsal, and right/left) begins to appear. At this stage, known as gastrulation, a flat and featureless sheet of cells folds into a living blueprint for
Generative chatbots promise personalized education at scale but struggle with accuracy issues
Personalized learning is a very effective teaching method, but its potential is limited due to resource constraints. In a small, in-person class, instructors can walk around, engage with students individually, adjust lessons and adapt their teaching to match each learner's
Rethinking where language comes from: Framework reveals complex interplay of biology and culture
A new study challenges the idea that language stems from a single evolutionary root. Instead, it proposes that our ability to communicate evolved through the interaction of biology and culture, and involves multiple capacities, each with different evolutionary histories. The
Theoretical framework for electrocatalysis expands clean energy production opportunities
An international study, involving researchers from the University of Tartu Institute of Chemistry, was recently published in Chemical Society Reviews. It provides the most comprehensive theoretical description to date of electrocatalysis and how its current limitations can be
Conductive hydrogel mimics brain softness for flexible bioelectronic devices
Bioelectronics, such as implantable health monitors or devices that stimulate brain cells, are not as soft as the surrounding tissues due to their metal electronic circuits. A team of scientists from the University of Groningen in the Netherlands, led by associate professor
Cellular crowding in fruit fly embryos triggers a critical DNA reorganization, biologists find
After fertilization, embryos race through rapid cell divisions before slowing down to build specialized cells that will carry out distinct functions in the developing body—but the signals that trigger this shift have remained a mystery.
Airborne sensors map ammonia plumes in California's Imperial Valley
A recent study led by scientists at NASA's Jet Propulsion Laboratory in Southern California and the nonprofit Aerospace Corporation shows how high-resolution maps of ground-level ammonia plumes can be generated with airborne sensors, highlighting a way to better track the gas.
Multicellular cyanobacteria switch gene activity between day and night cycles
Cyanobacteria, also known as blue-green algae, occur worldwide in many varieties, including in single-cell form and in chains called filaments. While these tiny life forms can strongly influence many ecosystems, the details of their behavior have mostly been studied in
Researchers uncover the source of widespread 'forever chemical' contamination in North Carolina
An environmental chemistry laboratory at Duke University has solved a longstanding mystery of the origin of high levels of PFAS—so-called "forever chemicals"—contaminating water sources in the Piedmont region of North Carolina.
Understanding bacteria's role in transforming steroids to pharmaceuticals
For decades, pharmaceutical companies have been using bacteria found in soil and water to chemically convert steroids into effective treatments for human diseases. One example is cortisol, which is used to treat asthma and skin rashes. But how bacteria convert steroids is not
Not just stomata: Hidden water regulation mechanism could help crops survive drought
Cornell researchers have discovered a previously unknown way plants regulate water that is so fundamental it may change plant biology textbooks—and open the door to breeding more drought-tolerant crops.
