Oustide feeds

In my last post I reported:

For the last century, … averaging over [3] LLMs, 89% of culture trends that can be classified are toward-forager.

And 81% of such trends can be so classified. For the prior two centuries this explanatory power was weaker (59%,65%), but still substantial. This suggests a way to predict the next century: predict toward forager trend changes.

So I collected 22 future trends that would plausibly be predicted by a continuing toward-forager-style trend. I then set aside these 7 trends as ones that could also be as plausibly predicted by increased wealth, education, or world connection:

↓ Fertility; ↑ Travel, Migration;↓ Nationalism;↓ Religion, ↑ Spirituality; ↑ Emotion Talk, Legitimacy; ↑ Flexible Work Hrs, Places; ↑ Casual Dress, Etiquette.

That left these 15 trends as better tests of the toward-forager hypothesis:

↑ Business Regulation; ↑ Kid Autonomy; ↑ Loose Drug Norms; ↑ Loose Sex Norms; ↑ Nature Sacred; ↑ Redistribution; ↓ Convict, Animal Cruelty; ↓ Family, ↑ Friends; ↓ Gender Roles; ↓ Institution Authority; ↓ Marriage; ↓ Militarism; ↓ Monogamy; ↓ Politics Via Orgs; ↓ Rank/$, ↑ Charisma.

To further consider this hypothesis, I asked poll respondents to rank, and 3 LLMs to predict, the chance that each will be a world trend over the next century. Here are human relative priorities and median LLM chances:

LLMs give a mean chance of 67%, about the fraction they said fit toward-forager trends in 1826-1926. So LLMs foresee a much lower predictive power for the next century, compared to the last century. But the correlation between humans and LLMs here is -0.06, so humans disagree with LLMs lots here. In a century we’ll have actual trend data to more directly see who was right.

In March, we reported on a wild bobcat that had been hit and dragged by a car, who also got her head stuck in the car’s grill. As if things could get any worse, the wild feline arrived at Raven Ridge Wildlife Center in Pennsylvania on a Sunday, and the nearby veterinary practice was closed. But thanks to two lucky acquaintances, a mobile x-ray machine was brought in, revealing that the bobcat had broken two legs. 

Thanks in part to the fact that her bone fractures were clean breaks, her team decided to risk a surgery. The next morning, two surgeons operated on the bobcat contemporaneously. After the operation, Tracie Young, director of the Raven Ridge Wildlife Center, told Popular Science that she was doing “fantastic” and “starting to act like a bobcat.” 

The female feline has been healing at Raven Ridge Wildlife Center for two months. Image: Dawn Rise Ekdahl / Raven Ridge Wildlife Center.

In her great misfortune, the cat has been rather lucky—and it seems like the luck is holding. Two striking coincidences have now come together to get her a custom-made cage for her rehabilitation. 

“After two months of recovery, the bobcat now needs to be moved outside for exercise and to begin building muscle tone,” the wildlife center wrote on social media. “We had to devise a safe and creative way to get her outdoors, necessitating the construction of special caging. We determined that a custom dog kennel would be the only viable option.”

However, the problems were twofold: time and money. The dog kennel builders the wildlife center contacted needed at least eight months to build the rehab cage, and the project would cost thousands of dollars. But then Raven Ridge’s photographer Dawn called her neighbor Glen for suggestions, who turned out to be the owner of a kennel-building business and could build the kennel in two weeks. 

The custom-built kennel was made for the bobcat in only two weeks. Image: Dawn Rise Ekdahl / Raven Ridge Wildlife Center.

And if you think that’s enough of a coincidence, it gets even better. The very day construction commenced, Raven Ridge Wildlife Center received a letter with a generous donation. A woman named Raven Minervino has passed away, and her husband wrote that she had consistently supported the wildlife center. After she died, her husband had asked that rather than getting flowers, people make donations in her memory. The letter had a donation in her memory large enough to pay for the custom bobcat cage.

“Thanks to all this support, we successfully moved the bobcat to the new enclosure, where she is now exploring, exercising, and much happier,” reads the social media post. Raven Ridge plans to (or perhaps already has) put a plaque in Minervino’s memory on the cage. 

Both of the bobcat’s broken legs have healed, and since having the custom cage, she has put on ten pounds, bringing her to the much healthier total of 19 pounds. Adult female bobcats weigh approximately 15 to 20 pounds on average

The post Bobcat that survived being hit by a car gets a custom-built kennel appeared first on Popular Science.

To effectively travel on Mars, rovers need to deal with a lot of sand. German engineers have created a new kind of ground rover that uses swimming motions to push through sand that may otherwise cause the  wheels to get stuck. Its inspiration: the African sandfish (Scincus scincus), a lizard known for burrowing into the Sahara Desert and literally swimming through its sand like a fish. It’s one of the animal kingdom’s strangest methods of propulsion, but it may help shape the future of Mars exploration.

A video of the rover, released this week by the University of Würzburg, shows a mini-fridge-sized, silver rover making its way through a sandy, Martian-mimicking test floor. Rather than rolling forward, each of its four wheels cuts through the sand in what looks like a figure-eight motion. The rover pushes on several yards and then cuts a corner and returns to where it started.

“The wheels mimic the animal’s [sandfish’s]characteristic interaction with the ground, generating both longitudinal and lateral forces,” University of Würzburg researcher Amenosis Lopez said in a statement. “The rover leaves sinusoidal tracks in the sand.” 

The sandfish: nature’s cute solution to slippery sand 

Though most people likely associate space rovers with round wheels or tracks reminiscent of those on WALL-E, neither design is ideal for dealing with Mars’s uniquely harsh and sandy environment. Sand is unique because it’s a material with both solid and liquid-like qualities. On top of sand’s mixed texture, rovers roaming on the Red Planet have to deal with steep slopes and uneven terrain, where varying levels of slipperiness can cause imbalance. Patches of softer sand are also a nightmare for wheels, making the prospect of a rover getting stuck never far from mind

But nature figured out a solution to this issue millions of years ago, and it’s called the sandfish. Contrary to its name, the Sahara Desert native is a lizard in the skink family. Above ground, the sandfish uses its tiny legs to scrabble around much the same as any lizard. Things get more interesting when it burrows down into the sand. X-ray imaging shows  the sandfish propelling itself forward under the sand, using a powerful waving motion to generate thrust and overcome drag. The result looks like an animal swimming through the sand, remarkably similarly to how a fish would oscillate its body to move through water

Engineers at Georgia Tech took those observations and used them to create their own sandfish robot in 2011. Testing with their robots showed that the little lizard’s oddly wedged shaped head may also help it generate lift forces and more easily swim through sand. 

Sink or swim: new rover did both 

Researchers working on the sandfish-inspired robot said it outperformed a wheeled version when navigating through a sandy test track. Where the round wheels would wobble and weave, the oscillating wheels stayed relatively stable. That’s not to say the new approach worked right out of the gate. Early models of the design were reportedly so heavy that the  rover literally sank into the sand. The team went back to the drawing board and made a second version, this time increasing each wheel’s width and reducing overall mass

It’s unlikely these oddball new wheels will become the main chassis system for NASA rovers, at least not in the immediate future. More work still needs to be done to increase their overall controllability and account for slippage that can occur in complicated, real-world environments. There are also the added variables of accounting for scientific instruments and other cargo a rover might have to carry. 

More than anything, the wheel design is a testament to the sandfish’s innate ingenuity and evolutionary gifts. Many scientists only recently began to truly appreciate these traits and what other technology they could inspire. 

The post New Mars rover could swim through sand like a desert lizard appeared first on Popular Science.

XAI AI data center economics are even better when you can start a project and finish it in 12 months and get it rented and paid off while competitors are still building. An active AI Gigawatt of data center in the hand is worth $20 billion per year while an under construction Gigawatt data center ...

Read more

XAI Colossus 1 and part of 2 is leasing to Anthropic for $15 billion per year. This will mean SpaceXAI will be able to have more deals to build faster with huge profits. They can be renting ½ of the new capacity to scale the earth based data centers to 100B+/year high-margin rental business by ...

Read more

For over ten millennia of the farming era, most folks saw themselves as tightly tied to small groups that lived in a largely alien and hostile world, under the thumb of empires and elites selected by tradition and power, elites not embarrassed by their privilege, interested in the general welfare, nor open to persuasion by argument. Few saw grand arcs of history as the sorts of things that they could or should much influence.

Today, in contrast, most people and especially elites see themselves as part of a single big world, with elites selected more by merit, embarrassed by unmerited privilege, interested in general welfare, and especially smart and open to persuasion. So we see world arcs and problems as things to be dealt with by smart elites talking stuff out until they agree, and most everyone is eager to join in such talk to seem like elites.

How did this change? In 2010, I started to explore this explanation: modern values are mainly a reversion to forager values.

[Forager] individuals who otherwise would be subordinated are clever enough to form a large and united political coalition. … the weak combine forces to actively dominate the strong. … They must continue such domination if they are to remain autonomous and equal, and prehistorically we shall see that they appear to have done so very predictably as long as hunting bands remained mobile. … Before twelve thousand years ago, humans basically were egalitarian. They lived in what might be called societies of equals, with minimal political centralization and no social classes. Everyone participated in group decisions, and outside the family there were no dominators. For more than five millennia now, the human trend has been toward hierarchy rather than equality. But the past several centuries have witnessed sporadic but highly successful attempts to reverse this trend. (More)

A lot of today’s political disputes come down to a conflict between farmer and forager ways, with forager ways slowly and steadily winning out since the industrial revolution. It seems we acted like farmers when farming required that, but when richer we feel we can afford to revert to more natural-feeling forager ways. (More)

In the absence of [big] threats, the talky collective was the main arena that mattered. Everyone worked hard to look good by the far-view idealistic and empathy-based norms usually favored in collective views. … When they felt on good terms with the group, people could relax and feel safe. They then become more playful, and acted like animals generally do when playful. Within a bounded safe space, behavior becomes more varied, stylized, artistic, humorous, teasing, self-indulgent, and emotionally expressive. For example, there is more, and more varied, music and dance. New possibilities are explored. (More)

We [today] … have a strong world culture of regulators, driven by a stronger world culture of elites. Elites all over the world talk, and then form a consensus, and then authorities everywhere are pressured into following that consensus. … This looks a lot like the ancient forager system of conflict resolution within bands. Forager bands would gossip about a problem, come to a consensus about what to do, and then everyone would just do that. … This world system [is] new … this looks like another way in which our world has become more forager-like over the last few centuries, as we’ve felt more rich and safe. (More)

Weak cultural selection pressures have allowed a drift back to forager habits and attitudes, which DNA makes still more natural than farmer alternatives. Our increased wealth, health, and peace now makes us unusually willing and able to indulge forager-style moral preferences. The usual forager view is this: we must coordinate via norms and governance to prevent dangerous competition from undermining our precious stable shared human values. (More)

I don’t claim to be totally original here. Let me credit sources who explored related ideas: Joshua Meyrowitz (1986) No Sense of Place, Friedrich Hayek (1988) The Fatal Conceit, Ernest Gellner (1994) Conditions of Liberty; Christopher Boehm (1999) Hierarchy in the Forest; Ronald Inglehart, Christian Welzel (2005) Modernization, Cultural Change, and Democracy; Peter Turchin (2105) Ultrasociety; Ian Morris (2015) Foragers, Farmers, and Fossil Fuels; James Suzman (2020) Work.

To test this basic idea, I asked 3 LLMs to find 100 cultural changes in the West in each of the periods 1400-1726, 1726-1826, 1826-1926, and 1926-2026, and then to score each change as more toward a forager style, more toward a farmer style, or hard to classify and thus neither. Here are their results:

For the last century, we see a strong correlation: averaging over LLMs, 89% of culture trends that can be classified are toward-forager. Making this return-to-forager-styles theory quite explanatory for that period. However, over the prior two centuries the correlation seems real but weaker, with 59% and then 65% of trends being toward-forager. For the earliest period of 1400-1726, the tendency was the opposite, with only 37% of trends were toward-forager.

To explain recent trends even better, let’s add in two more key changes: the world got both better connected and more educated. Increasing talk, travel, and trade made us intuitively feel part of much larger communities. So when our elites try to act like forager sitting around the campfire pontificating on their band’s problems, they see much larger social units as their “band”, often the whole world. And being better educated, elites now use much higher levels of abstraction and other mental tools of the educated when pontificating on big arcs and problems. Also, putting our young elites together in school has created strong youth cultures, which have for the last century driven rapid change in core cultural values.

This return to forager styles has created the intellectual world that I have known and loved all my life. The world in which I love to read, listen, write, and speak. And which sits adjacent to the songs, movies, art, etc. that I love. A world where, at its best, smart young people talk abstractly and idealistically about big issues and problems, and then greatly influence policy and culture. In the last few decades I’ve been associated with new groups like rationalists and effective altruists who have arisen in this mold.

Alas, I recently learned that forager-style elite talky collectives seem to be contributing to our civilization’s key problem of decline due to insufficient evolutionary pressures for dimensions of behavior not greatly under the control of capitalism, but instead subject to strong individual conformity pressures. Not only have youth movements been rapidly changing key cultural values with little regard to their adaptiveness, but our forager elite intellectuals have been overconfidently inducing over-regulation, severely limiting the scope of strong evolutionary pressures.

You see, ancient forager elites didn’t just consider in general how to promote their groups, they instead focused mostly on the possibility that some of group members might gain and use dangerous powers. Since then, people thinking like foragers have similarly focused on identifying and reigning in what they see as the dangerous potentially-ineqalitarian powers of their world. In the last few centuries, such dangers have included alien ideologies and militaries, capitalist owners and firms, and technologies like nuclear, genetic engineering, and AI. A lifetime of detailed examination of such things allows me to say with some confidence: we have consistently greatly over-regulated such things.

It is likely that our civilization will fall, to be replaced by much less forager-like versions. Like civs built by descendants of today’s Amish and Haredim. But I see a chance to save a lot, a chance I want to explore. Yes, this would require substantial compromise; we just can’t keep on relying on simple forager intuitions as naively as we have. But I do see a potential way out.

First, we’d need to adopt far more effective and accountable institutions for creating consensus on claims about the concrete consequences of policies. Institutions like policy decision markets or academic prestige futures. These could cut much of the bias in our policy choices, relative to our values. Second we’d need to either directly or indirectly show far more respect for adaptiveness when expressing our deep values. Either have big polities hold to sacred goals inconsistent with civ collapse, or smaller polities hold directly to their long term adaptiveness, both via rather competent governance institutions. Big asks, I know, but at least I see a chance here.

2034 Earth–Venus–Mars opportunity looks promising. 10–15 on-orbit refueling operations may be needed to make a crewed ship full. (A version 4 Starship could refuel with five tanker launches. Most refueling can be done at an altitude of 180–200 km, made possible by Starship’s size. The final refueling may be performed at a higher altitude of ...

Read more

Freda Duan estimates XAI Colossus 1 has ~$6B annual rent. Colossus 2 is leasing roughly one-third of its total compute capacity to $Anthropic. I am extending the analysis to renting out one third to one half of the new construction. This does not included distributed compute from Tesla cars, Tesla bots, new servers with Tesla ...

Read more

The twelfth flight test of Starship is preparing to launch Friday, May 22. The 90-minute launch window will open at 5:30 p.m. CT. Yesterdays, attempt was cancelled because the launch tower had a pin that did not retract. A live webcast of the flight test will begin about 45 minutes before liftoff, which you can ...

Read more

Cows are not necessarily known for their intelligence, but that less-than-stellar reputation is beginning to change. A 13-year-old pet cow in Austria named Veronika uses brooms to scratch her back, which qualifies as a form of tool use. Tool use is considered a general marker for intelligence in animals. The domestic cow species that live in close contact with humans are also highly social animals, another sign of intelligence. 

New research finds that one domestic species of cow (Bos taurus taurus) can recognize humans and distinguish between them. The cows show a visual preference for new human faces and can match a known handler’s voice to their face. The findings are detailed in a small study published today in the journal PLOS One.

To see whether cows can discriminate between familiar and unfamiliar faces, the team collected data from 32 Prim’Holstein cows. This breed originated in Holland and is the most common dairy cow breed in France. In one single lactation, they can generate about 22,000 pounds of milk. 

The team played videos of familiar and unfamiliar male faces with the sound off for the cows, and measured how long the animals looked at the video. Specifically, the team was looking for cross-modal recognition, or the cognitive ability to recognize objects presented in two different sensory settings. 

They also played videos of both familiar and unfamiliar human faces, while broadcasting audio corresponding to one of the two men. Each man also said the same sentence. The team measured the animals’ heart rates as they watched the videos, to see if the bovines responded to the videos emotionally. 

Experimental setup for visual preference and cross-modal tests. The cow was positioned centrally between two screens. Each screen showed a video of a person’s face: one familiar and one unfamiliar to the cow. During cross-modal tests, a speaker placed between the screens played the voice of one of the two individuals. Cameras recorded the cow’s behavioral responses throughout the test. Image: Amichaud et al., 2026, PLOS One, CC-BY 4.0

The cows were not afraid of the videos without sound and stared at the unfamiliar faces longer. According to the team, the staring shows that the animals can distinguish between an unknown and known face. 

When researchers paired the videos with sound, the cows spent more time staring at the video when the voice matched the face. This shows that the cows can pair a face with the voice that they know. Captive big cats can also do this with their handlers. 

Based on their heart rate, neither the familiar or unfamiliar voices appeared to affect the cows’ emotional response. 

The team notes that a video and sound recording are not a full interaction with a human, but these results indicate that cows can tell the difference between familiar and unfamiliar people, and they can tell humans apart by face and voice. To better understand the animals and their welfare, future studies could examine how cows interact with specific people.

The post Cows can tell humans apart, new study finds appeared first on Popular Science.

NASA’s Psyche spacecraft is currently en route to a small, metal-rich asteroid near Jupiter. However, the barely 3,600-pound probe recently required a little help from Mars to complete its lengthy 2.2-billion-mile mission. Despite its complex gravity assist earlier this month, the groundbreaking spacecraft still found time to snap some travel photos showcasing its Red Planet flyby. NASA released the latest image from Psyche’s trip on May 20, which offers a gorgeous view of Mars just hours before Earth’s neighbor temporarily eclipsed the cosmic traveller.

According to NASA, the image was taken on May 15 at about 8:03 a.m. EDT by the spacecraft’s multispectral imager instrument. The thin crescent view of Mars is due to the spacecraft’s approach at what’s known as a high phase angle. The fingernail slice of Red Planet actually looks brighter and wider than mission specialists anticipated, thanks to a large level of sunlight scattering through the dusty Martian atmosphere. Interestingly, the instrument’s original unfiltered image wouldn’t look very discernible to the human eye. Instead, scientists processed the photo into a natural-color palette using the probe’s red, blue, and green imager filter data.

Launched in October 2023, Psyche is destined for 16 Psyche, a 140-mile-wide rock that astronomers theorize may be the remnant of an ancient planetary core. Once there, the spacecraft will study its iron magnetic properties, as well as use its imagers and spectrometers to analyze the asteroid’s chemical and elemental compositions. 

Thanks to the Martian gravity assist, Psyche is scheduled to reach its destination in 2029. At its closest pass, Psyche swung around the Red Planet barely 2,800 miles above the surface at a speed of around 12,333 miles per hour.

The post Mars shines in ethereal photo from Psyche space probe appeared first on Popular Science.

What’s the weirdest thing you learned this week? Well, whatever it is, we promise you’ll have an even weirder answer if you listen to Popular Science’s hit podcast. The Weirdest Thing I Learned This Week hits Spotify, YouTube, Apple, and everywhere else you listen to podcasts every-other Wednesday morning. It’s your new favorite source for the strangest science-adjacent facts, figures, and Wikipedia spirals the editors of Popular Science can muster. If you like the stories in this post, we guarantee you’ll love the show.

FACT: There’s more than one way to sterilize a hippo, but there’s no easy way to sterilize a hippo

By Rachel Feltman

If you’re a longtime fan of Pablo Escobar’s hippos, you may have heard that their time is running out. After years of trying to deal with these feral hippos conservatively, the Colombian government recently announced that they’ll have to cull some of them to curb their rampant population growth. An Indian billionaire did recently make a last-minute offer to save the hippos at any cost, but transporting a grown hippo—an incredibly deadly animal that weighs literal tons—is no easy feat, so it’s likely that some, if not all, of the planned culling will still take place.

This is not for lack of trying. Like, seriously: The government really, really tried to avoid killing any hippos. But the years-long effort to sterilize these animals has largely failed, and researchers say we’re running out of time to avoid a population too large to deal with. That got me wondering… what makes it so difficult to sterilize a hippo?

As you’ll learn in this week’s episode, sterilizing a hippo surgically is a difficult, dangerous, and expensive endeavor. And while chemical castration (AKA shooting hippos with birth control darts) might sound simpler, it’s… still difficult, dangerous, and expensive. 

For a hippo palate cleanser, I also dive into the herculean effort made to save Fiona the hippo a few years back, which required milking a hippo (a feat never before attempted!) and replicating hippo milk.    

FACT: John Steinbeck took part in a failed deep-sea drilling expedition

Featuring Ben Lillie (the co-founder of Caveat, our favorite venue in NYC!)

This week’s episode features special guest Ben Lillie, otherwise known as the keeper of our favorite place to do Weirdest Thing live shows! He spun a yarn about Project Mohole, a failed deep-sea drilling expedition that took place back in the 1960s. The expedition featured a surprising crew member: John Steinbeck, who covered the endeavor for LIFE Magazine in… very Steinbeck-ian fashion. 

Ben came across this story while working on a live show all about jargon. You can catch that show live and in-person at Caveat on Wednesday, May 27. 

FACT: Joseph Pilates didn’t mean for his workout to get so bougie

By Sara Kiley Watson

Pilates is a super trendy workout modality right now, and it’s gotten a reputation for being pretty elitist. But Joseph Pilates—yes, he was a real guy, and his name was Pilates—didn’t set out to create a workout that looked good on the ‘gram. He didn’t even set out to create a workout that people would spend loads of money on. The former circus performer actually dreamed up the exercises that would become pilates while interned in a prison camp. You can learn more about the reformer’s journey from janky hospital bed to sleek boutique workout equipment in this week’s episode, or by checking out this article I wrote about the history of Pilates. 

The post There’s more than one way to sterilize a cocaine hippo. Unfortunately, both ways suck.  appeared first on Popular Science.

Long before humans smacked “delete” to obliterate typos, we fixed mistakes and revised written language the old-fashioned way: by rubbing errors clean off the page.

The quintessential pink eraser is now a mainstay in household junk drawers, classrooms, and office supply cabinets, but how exactly do these ingenious little pieces of technology work? How do erasers erase?

The history of erasers

Humans have marked stuff with graphite for thousands of years. However, modern pencils—which encase graphite, or a mixture of graphite and clay, in wood—date back to the 17th century. 

Contemporary erasers, meanwhile, came fashionably late. Their precursors include balled-up stale bread and wax. Then, in the 18th century, natural rubber was used as an eraser. Later, in the 19th century, raw rubber erasers were toughened up with heat and sulphur. And, finally plastic erasers debuted in the 20th century. Whether erasers were snackable, heat-treated, or even electrified, the fundamentals of erasing remain. Pencils and erasers work together through the forces of attraction—and friction.

A late 19th century postcard shows people harvesting natural rubber from rubber trees. Early erasers were made using natural rubber. Image: Contributor / Getty Images / Sepia Times

“When you run a pencil over paper, tiny little pieces of carbon flake off and stay on the paper, and that’s what leaves the pencil mark,” Dr. Joseph A. Schwarcz, a chemistry professor who directs the Office for Science and Society at McGill University, tells Popular Science. The pencil’s “lead”—a misnomer, as it’s not actually lead—isn’t just lodged between the fibers in paper; as graphite particles shear off, they also sit atop the page and remain there due to “a very small attraction between molecules,” Schwarcz explains. 

That’s where the eraser comes in, Schwarcz says. “There’s a greater adhesion of those little [graphite] particles to rubber than to the paper, so when you rub the rubber over the paper, it removes them.”

Several thousand years before colonizers commercialized rubber, Mesoamericans developed tools and recreational items with natural latex by tapping and processing the fluid in native rubber trees. While synthetic erasers, composed of substances such as polyvinyl chloride, are now more popular than natural rubber in some parts of the world, all erasers generally work the same way: “The graphite particles are attracted more to the eraser than they are to the paper,” says Schwarcz. 

“There’s also a slight abrasion effect, where you’re dislodging the graphite particles by friction,” Schwarcz adds. This process erodes some of the paper, which helps explain why so many different varieties of erasers exist; softer erasers tend to be gentler on the page, while firmer erasers are generally more durable and precise. 

The science behind the attraction

The chemical attractions Schwarcz describes are called van der Waals forces. “Molecules have tiny little charges distributed over the atoms, and the positive charges will attract the negative charges. So paper will have some molecules with negative charges that are attracted to the positive surfaces of the graphite,” Schwarcz says. Basically, when you write with a pencil, the graphite stays on the page thanks to forces of attraction.

But the attraction between graphite and paper is pretty weak. So when you rub an eraser on a piece of paper, friction basically disrupts the attraction between the graphite and the page, and the graphite that was once on the paper ends up sticking to the eraser.

On a molecular level, graphite is made up of many two-dimensional sheets of carbon, known as graphene, stacked one upon another and held together by van der Waals forces. 

“There’s this cloud of electrons on one layer of graphene, and another cloud of electrons on another layer of graphene,” Dr. Justin Caram, an associate professor of chemistry at the University of California, Los Angeles, tells Popular Science. The electrons on these sheets can “randomly fluctuate” to make one side a little positively charged, and the other a little negatively charged. 

“Because positive and negative charges interact with each other, that binds things together,” Caram says. In other words, we have van der Waals forces to thank for why graphite sticks together on a page.

Although individual sheets of graphene are “completely neutral and have no intrinsic dipole”—or inherently positive and negative side—“they still interact with each other because of these random fluctuations.” Caram adds, “That’s what a van der Waals force is. It’s basically a force between any two things where the electrons can move around and compensate for one another,” keeping things together—if somewhat weakly.

Related 'Ask Us Anything' Stories

Color doesn’t exist—at least not how you think

Chess or video games—which actually makes you smarter? The answer may surprise you.

Why our ancestors had straight teeth without braces

Are induction stoves better? These chefs think so.

How do airplane toilets work?

What really happens to your bag after you check it in?

What about erasable markers and inks?

Whiteboard markers and dry erasers function similarly to pencil erasers but with added complexity, incorporating a slick writing surface to prevent ink absorption and an oily release agent to suspend ink over the board. A quick swipe of a dry eraser easily disrupts the bond between the oily agent and the whiteboard.

However, some erasable inks work differently. Penmakers such as Pilot use thermochromic ink that responds to temperature changes (sort of like a mood ring), becoming clear when exposed to heat. 

So as you rub an eraser against the page, this friction boosts temperatures above 140 degrees Fahrenheit, triggering a regulator in the ink. This temporarily breaks “the bond between the color former and the color developer,” writes Pilot, “effectively erasing your writing.” 

The word “effectively” is doing a whole lot of work in this sentence, because whatever you’ve written is still technically there—absorbed into the paper. Pilot explains: “With enough cooling, (like placing the paper in a freezer), at approximately [negative four degrees Fahrenheit], the components would combine again, and your writing could reappear!”

To err(ase) is human

Ink isn’t usually reactive to temperature like erasable inks, making it tricky or impossible to “erase” errors without marring writing surfaces like paper. “Ink is carried by liquid into the fibers [ of a piece of paper], and when the liquid dries the ink stays behind,” says Caram. Compared to graphite, “it’s much more embedded in the actual molecular network that makes up the paper.”

Mass-produced correction fluids, pens, and tapes (think: Wite-Out, Tipp-Ex, and Liquid Paper) took off in the mid-20th century to conceal inky, typewritten mistakes. Yet, the underlying concept of covering up errors by effectively painting over them is much older. 

Ancient artisans in Egypt used white paint to cover up errors on papyrus, including to narrow the gut of a jackal in an illustration from the Book of the Dead, researchers at Cambridge’s Fitzwilliam Museum said in March.

A secretary uses an eraser to fix a mistake on a page in her Underwood typewriter in a photograph taken around 1945. Image: Stringer / Getty Images / Herbert

Many pencils now feature built-in erasers, an innovation that was first patented in Philadelphia in 1868. Yet, as inseparable as they now seem, modern pencils and erasers didn’t wed right away. 

Japanese pencil and stationery maker Tombow, for example, released its first pencil in 1913; the company tells Popular Science that it developed its first eraser, the Iron Helmet Eraser (“Tetsu-kabuto Jikeshi”), 26 years later. 

Due to “wartime economic blockades,” Tombow said its initial eraser was “manufactured using oils and fats instead of natural rubber.” Material shortages later drove the development of plastic erasers. 

Now, even as screen time defines much of modern life, the modern pencil and eraser live on, as students, artists, and office workers snap them up by the billions each year. 

With pencil and pen sales projected to rise (and autocorrect now ever present in written communication), errors and revisions haven’t really gone anywhere; some tools just make them more (or less) obvious to others. 

Whether you’re a scribe touching up a sacred text or a student erasing doodles in the margins, mistakes are only human. And one way or another, covering them up is, too.

In Ask Us Anything, Popular Science answers your most outlandish, mind-burning questions, from the everyday things you’ve always wondered to the bizarre things you never thought to ask. Have something you’ve always wanted to know? Ask us.

The post How do erasers actually work? It’s surprisingly complicated. appeared first on Popular Science.

Tyrannosaurus rex is iconic for its ferocity and big teeth, as well as those teeny-tiny arms. The Cretaceous Period apex predator wasn’t the only carnivore with underdeveloped forelimbs, however. At least five groups of two-legged, mostly meat-eating theropod dinosaurs experienced a shortening of the upper arms over the course of their evolutionary journey. But why did they have such comically small claws? One team of researchers believes the answer is simple.

“It’s a case of ‘use it or lose it,’” University College London paleontologist Charlie Scherer said in a statement.

Scherer and his colleagues recently examined the data for 82 theropod species, including those in T. rex’s tyrannosaurid family. Their study published today in the Proceedings of the Royal Society B Biological Sciences argues a combination of massive skulls and crushing jaws—coupled with increasingly large prey—had many theropods relying increasingly less on their forearms.

“We sought to understand what was driving this change and found a strong relationship between short arms and large, powerfully built heads,” explained Scherer. “The head took over from the arms as the method of attack.”

The team based their conclusions on a new system of assessing dinosaur skull strength based on attributes like overall dimensions, how tightly bones were joined in the head, and bite force. Unsurprisingly, T. rex came in first place for bite force, followed by the Tyrannotitan. Almost as large as a T. rex, the Tyrannotitan lived in present-day Argentina during the Early Cretaceous over 30 million years before its famous descendent. In each example, the reason for short arms likely coincided with hunting larger and larger dinner targets.

“Trying to pull and grab at a 100–foot–long sauropod with your claws is not ideal. Attacking and holding on with the jaws might have been more effective,” added Scherer.

Overall, the team identified a bigger correlation between skull strength and smaller arms than with either skull or body size. This conclusion is further supported by some theropod dinosaurs with strong heads, tiny forelimbs, and a relatively small stature. For example, Majungasaurus roamed present-day Madagascar 70 million years ago while weighing about 1.75 tons—around a fifth the size of T. rex.

Not every dinosaur’s limbs shrank in the same way, either. Abelisaurids like Majungasaurus exhibited smaller arms past their elbows as well as their hands, while tyrannosaurid arms reduced proportionally. In each case, it seems that the theropods initially had far more success latching onto prey with their powerful jaws, then evolution did the rest of the work.

As to which dinosaur had the teeniest forearms, the answer according to Scherer is clear.

“The Carnotaurus had ridiculously tiny arms, smaller than the T. rex,” he said.

The post Why were T. rex’s arms so tiny? Paleontologists finally find an answer. appeared first on Popular Science.

The happy-face spider (Theridion grallator) is famous for the particularly cheery looking patterns on top of its abdomen. Ecologists in Hawaii first described the tiny, vibrantly green arachnids in 1900, and have long assumed them to be unique to the islands. However, an unexpected encounter thousands of miles away recently surprised researchers combing through the forested slopes of the Himalayan mountains.

According to their study published in the journal Evolutionary Systematics, there is at least one more smiley spider species in the world. Of course, such a discovery deserves an equally appropriate name. Without further ado, it’s time to meet the Himalayan happy-face spider (Theridion himalayana).

Mature male (left) and female (right) of Theridion himalayana sp. nov. Credit: Devi Priyadarshini and Ashirwad Tripathy.

The meetup began in 2023 during an expedition in the northern state of Uttarakhand, a region home to many animals that remain unknown to science. Researchers from India’s Forest Research Institute and the Regional Museum of Natural History intended to catalogue ant biodiversity at the foot of the Himalayan mountains, but they kept getting distracted by the insects’ eight-legged neighbors.

“My co-author [Ashirwad Tripathy] kept sending me spiders from high altitude regions for identification,” Regional Museum of Natural History biologist Devi Priyadarshini said in a statement.

Priyadarshini recalled on “one fine day,” her colleague sent a photo of an arachnid clinging to a Daphniphyllum leaf. That was when she “froze in shock.”

“I had seen the Hawaiian spider during my master’s program…I knew instantly we had a jackpot because of its striking resemblance,” explained Priyadarshini.

Over the next few months, Tripathy continued to document every similar spider he saw during his survey. While each of the 32 examples clearly belonged to the same species, they all showcased an array of smiley dot-and-stripe coloration patterns (known as morphs) on their bodies. Once in the lab, the team conducted a DNA analysis of their specimens and discovered about an 8.5 percent genetic variation from the Hawaiian happy-face spider. This confirmed it evolved completely independent of the almost identical island spiders, thus earning the name Theridion himalayana.

“The name [Theridion] Himalayana was decided as the species name because we both wanted to pay our respects to the mighty Himalaya mountain ranges, which have been standing tall not just guarding our country but also holding a plethora of biodiversity within them,” added Tripathy.

Although the green coloration obviously helps both spiders blend into the surrounding vegetation, the exact reason for their back patterns remains unclear. Priyadarshini said this question is “definitely indicative of a deeper genetic mystery” that deserves further investigation. However, another shared trait is even stranger. Both species have a fondness for ginger plants, even though ginger isn’t native to Hawaii.

“How did the [Hawaiian] spiders choose an invasive species and ginger exactly?” wondered Priyadarshini, who theorized T. himalayan may be an “elder cousin” of T. grallator.“Although this sounds like a tall claim now, it will be our further scope of work to establish any missing links,” she said.

The post Newly discovered spider has smiley face on its back appeared first on Popular Science.

There’s a SMILE beaming down from high above Earth. On May 19, the European Space Agency (ESA) and the Chinese Academy of Sciences (CAS) launched a Vega-C rocket from Europe’s Spaceport in French Guiana with a payload representing years of international collaboration. Known as the Solar wind Magnetosphere Ionosphere Link Explorer (SMILE), the spacecraft will soon begin studying the sun’s immensely powerful solar winds and their relationship with Earth’s atmospheric safeguards.

You wouldn’t be reading this without our magnetosphere. The protective shield generated from deep inside Earth has protected the planet from the sun’s most destructive solar winds for billions of years. Without this barrier, life could never survive on what would be a barren, irradiated rock. But while it’s clear that the magnetosphere is Earth’s natural defense system against cosmic radiation and geomagnetic storms, astronomers still aren’t sure exactly how it works. 

“We are about to witness something we’ve never seen before—Earth’s invisible armor in action,” ESA director general Josef Aschbacher said in a statement.

Over the next month, SMILE will slowly increase its altitude with 11 engine burns before settling into a large elliptical orbit over the North and South Pole. Actual data collection will start in July using the spacecraft’s four tools, including a pair of X-ray and ultraviolet cameras. 

SMILE is the first mission to examine the magnetosphere with X-rays, and the UV equipment will capture the northern and southern lights for up to 45 hours at a time. By combining the two data sources, astronomers hope to gain a better understanding of how the planet is affected by the sun’s constant bombardment of solar winds and frequent coronal mass ejections. The project is planned to last three years.

“The evidence that Smile collects will help us better understand planet Earth and our Solar System as a whole,” explained ESA Smile project scientist Philippe Escoubet. “And the science it uncovers will improve our models of Earth’s magnetic environment, which could ultimately help keep our astronauts and space technologies safe for decades to come.”

The post SMILE spacecraft will use X-ray vision to study the northern lights and more appeared first on Popular Science.

While every bumble bee colony has a queen, the process for becoming that queen bee may be a bit more democratic than monarchical. The worker bees appear to select which baby will be queen one day, according to a new study published in the journal Insect Biochemistry and Molecular Biology.

The key to this selection process lies in the juvenile hormone. This hormone in insects is responsible for their development, molting, and eventual reproduction. When the team gave the juvenile hormone to worker bees, they passed it along to all of the larvae in the colony through feeding. The more juvenile hormone the larvae received, the more likely they were to become queen. 

According to the team, this is the first study to show that bumble bee caste is determined by the workers and shifts our understanding of bee colony dynamics. Instead of a top-down hierarchy, the colony appears to be a more decentralized system, where the caregivers and workers can alter the future of baby bees. 

Less like Mean Girls?

Understanding the fate of the bee larvae is key to understanding their social behavior. Their whole system relies on a division of reproductive labor—some females will reproduce, while the others help. 

“Since all these females share the same DNA, it’s a striking example of how the same genotype can produce very different forms,” Etya Amsalem, a study co-author and entomologist at Penn State, said in a statement. “It’s also a practical question since bumble bees are important for pollination, so knowing how to produce queens could improve commercial breeding and management.”

In addition to their different social roles, queen bees and worker bees are also very different physically. Bumblebee queens are larger, live longer lives, and will reproduce. Worker bees are smaller in stature and do not reproduce or live as long.

While it was clear that hormones were involved in how workers determine the queen, the exact mechanisms behind it were more vague. 

“A single female egg in bumblebees holds the blueprint for two completely different life paths: the giant, reproductive queen or the small, sterile worker,” added study co-author and postdoctoral researcher Seyed Ali Modarres Hasani. “We wanted to understand what triggers the change in the female life trajectory, when does it happen and who controls the process.”

A matter of hormones

In the study, the team used three worker bees and a cluster of larvae. They applied juvenile hormone at different doses and times, and administered it either to workers or directly to larvae. They then traced the hormone’s movement, measuring  larval mass and recording which individuals became queens or workers.

“Every colony will produce many new queens at the end of the season,” Amsalem said. “These queens will leave the colony, mate and go into winter diapause, and then each queen will start a new colony in the next spring. In that sense, producing as many queens—and males—at the end of the season is the ultimate purpose of the colony.”

When the juvenile hormone was applied directly to the larvae, not only did they not turn into queens, but the worker bees ended up eliminating most of these larvae.

When the workers were treated with the juvenile hormone, they put it into the food that they make for the larvae. These larvae then ingested the hormone, and were heavier and much more likely to become queens.

“We also determined that larvae are only sensitive to this hormone on days seven and eight of their development,” Hasani said. “By tracing the juvenile hormone, we saw that the workers pass the hormone into the food they make from nectar and pollen.”

Queen development and the colony’s future

These results suggest that queen production is linked to how the colony progresses through the summer’s warmer months until it eventually collapses in the fall.

“Bumblebee workers do not reproduce when the colony is young, but they can activate their ovaries and produce males as the colony ages, which causes an increase in juvenile hormone levels,” Amsalem said. “As a result, over time, they feed larvae more of the hormone. When enough workers do this simultaneously, usually towards the end of the season, larvae receive doses that are high enough during the critical window to develop into queens.”

These results could help improve bee colony management at a hormonal level, explain how complex insect societies evolve, and how hormonal signals interact to shape colony structure.

The post Worker bees have power to pick their queen appeared first on Popular Science.

Torrance, United States / California, 19th May 2026, CyberNewswire

New York, United States, 19th May 2026, CyberNewswire

For decades, many paleoarchaeologists believed Neanderthals went extinct largely because they just weren’t intelligent enough to compete with their Homo sapien relatives. However, mounting historical evidence suggests this was far from the case. The latest discovery to help the Neanderthal’s reputation ion? The ancient hominins knew when and how to safely snack on shellfish potentially thousands of years before their human descendants.

The findings published today in the Proceedings of the National Academy of Sciences focus on Neanderthals who lived at Los Aviones Cave in present-day Cartagena, Spain. Researchers discovered the remains of 115,000-year-old mollusks including gastropods and limpets that were clearly harvested as food. This contradicts past theories about Neanderthals, which suggested they had difficulty adapting to coastal environments and utilizing marine resources. What’s more, the Neanderthals here didn’t eat shellfish in large quantities all the time. Instead, they knew to make the most of them between November and April during the colder seasons.

Los Aviones Cave in Spain is a notable Neanderthal archaeological site. Credit: ICTA-UAB

“They consumed marine resources throughout the year, but with a very clear preference for winter and autumn months,” explained Asier García-Escárzaga, a study co-author and archaeologist at Spain’s Universitat Autònoma de Barcelona Institute of Environmental Science and Technology.

García-Escárzaga says this seasonal pattern often followed by more modern human populations in Europe wasn’t a coincidence. The winter reproduction cycle of many mollusks also results in higher amounts of meat as well as improved flavor and texture. Summer months increase health risks like toxic algae contamination or rapid spoiling.

But how did researchers determine exactly when these shellfish were harvested? It all has to do with the mollusks’ shell carbonate and their oxygen isotopic levels. This level fluctuates depending on seawater temperature and functions like a “prehistoric thermometer,” according to García-Escárzaga.

The findings reveal that Spain’s coastal Neanderthals relied on a diverse diet featuring high-quality oceanic proteins filled with Omega-3 and zinc, both of which aid in reproductive health and brain development. With that in mind, it’s entirely possible that humans’ closest evolutionary ancestors influenced our own love of shellfish.

“What we see at Los Aviones is a fully modern subsistence strategy,” García-Escárzaga and his colleagues wrote in their study.

The post Neanderthals dined on shellfish much earlier than humans appeared first on Popular Science.