While the Clovis points needed frequent sharpening and broke easily, the hunters were surprised at how well they functioned as butchering tools. They gained a greater appreciation for the ingenuity of their Stone Age counterparts and were listed as co-authors on a paper published earlier this year describing the results of the experiment.

Target practice

Most of Eren’s students (and the occasional visiting journalist) get the chance at some point to throw point-tipped spears at a hunting target outside on campus, using an attached atlatl or spear-thrower. This ingenious handheld rod-shaped device employs leverage to launch a dart or spear. Versions have been developed by several different ancient cultures, including Aztec, Maya, Greek, Roman, and Australian aboriginal designs.

And as Eren’s colleague Michelle Bebber—an expert in ceramics and pottery (who also participated in the frozen feces study)—discovered in 2023, the atlatl is essentially the great equalizer between women and men. She noticed that her male students struggled more than female students to pick up the crucial whip action required because they were so accustomed to relying on strength and turned it into a blind test. She found that, unlike the javelin, the atlatl equalizes the velocity of female- and male-launched projectiles. It’s not even exclusively a gender difference, according to Bebber, since children, older men, or injured men would also have benefited from its use.

Although throws made with the atlatl are faster, the javelin has more kinetic energy because of its higher mass. Eren also experimented with throwing from different heights, renting a scissor lift for the purpose. “We wanted to understand how much more velocity and kinetic energy does gravity lend to these projectile weapons as you get higher,” said Eren.

Eren’s lab regularly makes replica spears for target practice.

Jennifer Ouellette

Eren’s lab regularly makes replica spears for target practice. Jennifer Ouellette

A handy target.

Jennifer Ouellette

A handy target. Jennifer Ouellette

Eren demonstrates proper form when throwing a spear with an atlatl.

Jennifer Ouellette

Eren demonstrates proper form when throwing a spear with an atlatl. Jennifer Ouellette

A handy target. Jennifer Ouellette

Eren demonstrates proper form when throwing a spear with an atlatl. Jennifer Ouellette

Eren’s shots are the ones that hit the mark. Mine? Not so much.

Jennifer Ouellette

Eren displays different kinds of tipped spears.

Jennifer Ouellette

A closer look at the different heads.

Jennifer Ouellette

Running a ballistics test with the spears.

Jennifer Ouellette

He found that the javelin increased not only in velocity but kinetic energy—almost a 200 percent increase in impact energy by 9 meters in height. But the atlatl decreased as the height increased. “If you are throwing down, the lever is deactivated,” Eren explained. “And because the darts are so light, they have higher velocity when traveling horizontally, but once the lever is deactivated, the wind can make it go sideways, producing more drag. That had never occurred to us, that the atlatl actually has a major cost if you are firing downward.”

https://arstechnica.com/science/2025/01/inside-the-hands-on-lab-of-an-experimental-archaeologist/

The dueling dialogs in this example are by no means unique to macOS.

Too many cooks in the kitchen

“Most try to funnel you into a vendor’s sync passkey option, and don’t make it clear how you can use other things,” Brown noted. “Chrome, Apple, Windows, all try to force you to use their synced passkeys by default, and you have to click through prompts to use alternatives.”

Bruce Davie, another software engineer with expertise in authentication, agreed, writing in an October post that the current implementation of passkeys “seems to have failed the ‘make it easy for users’ test, which in my view is the whole point of passkeys.”

In April, Son Nguyen Kim, the product lead for the free Proton Pass password manager, penned a post titled Big Tech passkey implementations are a trap. In it, he complained that passkey implementations to date lock users into the platform they created the credential on.

“If you use Google Chrome as your browser on a Mac, it uses the Apple Keychain feature to store your passkeys,” he wrote. “This means you can’t sync your passkeys to your Chrome profile on other devices.” In an email last month, Kim said users can now override this option and choose to store their passkeys in Chrome. Even then, however, “passkeys created on Chrome on Mac don’t sync to Chrome in iPhone, so the user can’t use it seamlessly on Chrome on their iPhone.”

Other posts reciting similar complaints are here and here.

In short, there are too many cooks in the kitchen, and each one thinks they know the proper way to make pie.

I have put these and other criticisms to the test over the past four months. I have used them on a true heterogeneous environment that includes a MacBook Air, a Lenovo X1 ThinkPad, an iPhone, and a Pixel running Firefox, Chrome, Edge, Safari, and on the phones, a large number of apps, including those for LinkedIn, PayPal, eBay, Kayak, Gmail, Amazon, and Uber. My objective has been to understand how well passkey-based authentication works over the long term, particularly for cross-platform users.

https://arstechnica.com/security/2024/12/passkey-technology-is-elegant-but-its-most-definitely-not-usable-security/

It feels like tech workers have caught very few breaks over the past several years, between ongoing mass layoffs, stagnating wages amid inflation, AI supposedly coming for jobs, and unpopular orders to return to office that, for many, threaten to disrupt work-life balance.

But in 2024, a potentially critical mass of tech workers seemed to reach a breaking point. As labor rights groups advocating for tech workers told Ars, these workers are banding together in sustained strong numbers and are either winning or appear tantalizingly close to winning better worker conditions at major tech companies, including Amazon, Apple, Google, and Microsoft.

In February, the industry-wide Tech Workers Coalition (TWC) noted that “the tech workers movement is far more expansive and impactful” than even labor rights advocates realized, noting that unionized tech workers have gone beyond early stories about Googlers marching in the streets and now “make the headlines on a daily basis.”

Ike McCreery, a TWC volunteer and ex-Googler who helped found the Alphabet Workers Union, told Ars that although “it’s hard to gauge numerically” how much movements have grown, “our sense is definitely that the momentum continues to build.”

“It’s been an exciting year,” McCreery told Ars, while expressing particular enthusiasm that even “highly compensated tech workers are really seeing themselves more as workers” in these fights—which TWC “has been pushing for a long time.”

In 2024, TWC broadened efforts to help workers organize industry-wide, helping everyone from gig workers to project managers build both union and non-union efforts to push for change in the workplace.

Such widespread organizing “would have been unthinkable only five years ago,” TWC noted in February, and it’s clear from some of 2024’s biggest wins that some movements are making gains that could further propel that momentum in 2025.

Workers could also gain the upper hand if unpopular policies increase what one November study called “brain drain.” That’s a trend where tech companies adopting potentially alienating workplace tactics risk losing top talent at a time when key industries like AI and cybersecurity are facing severe talent shortages.

https://arstechnica.com/tech-policy/2024/12/from-ai-to-rto-unpopular-policies-may-fuel-tech-worker-movements-in-2025/

So here’s to you, Stardew Valley. You were one of the brightest parts of my 2024, and a game that I already know I’ll return to for years.

— Lee Hutchinson

Grounded

Obsidian; Windows, Switch, Xbox, PlayStation

My favorite discovery this year has probably been Grounded, a Microsoft-published, Obsidian Entertainment-developed survival crafting game that was initially released back in 2022 (2020 if you count early access) but received its final planned content update back in April.

You play as one of four plucky tweens, zapped down to a fraction-of-an-inch high as part of a nefarious science experiment. The game is heavily inspired by 1989’s classic Honey, I Shrunk the Kids, both in its ’80s setting and its graphical design. Explore the backyard, fight bugs, find new crafting materials, build out a base of operations, and power yourself up with special items and steadily better equipment so you can figure out what happened to you and get back to your regular size.

Grounded came up because I was looking for another game for the four-player group I’ve also played Deep Rock Galactic and Raft with. Like Raft, Grounded has a main story with achievable objectives and an endpoint, plus a varied enough mix of activities that everyone will be able to find something they like doing. Some netcode hiccups notwithstanding, if you like survival crafting-style games but don’t like Minecraft-esque, objective-less, make-your-own-fun gameplay, Grounded might scratch an itch for you.

— Andrew Cunningham

Fights in Tight Spaces

Ground Shatter; Windows, Switch, Xbox, PlayStation

I spent a whole lot of time browsing, playing, and thinking about roguelike deckbuilders in 2024. Steam’s recommendation algorithm noticed, and tossed 2021’s Fights in Tight Spaces at me. I was on a languid week’s vacation, with a Steam Deck packed, with just enough distance from the genre by then to maybe dip a toe back in. More than 15 hours later, Steam’s “Is this relevant to you?” question is easy to answer.

Back in college, I spent many weekends rounding out my Asian action film knowledge, absorbing every instance of John Woo, Jackie Chan, Jet Li, Flying Guillotine, Drunken Master, and whatever I could scavenge from friends and rental stores. I thrilled to frenetic fights staged in cramped, cluttered, or quirky spaces. When the hero ducks so that one baddie punches the other one, then backflips over a banister to two-leg kick the guy coming up from beneath? That’s the stuff.

https://arstechnica.com/gaming/2024/12/ars-favorite-games-of-2024-that-were-not-released-in-2024/

That’s about all I need from a “mix up your takeout and use the right apps” app, one made mostly for me, my spouse, and nearby friends and visitors. Pretty much anything you’d find useful while sitting down at a spreadsheet, you can also make useful through a little phone webapp.

Joyful overkill

I went a good deal further with my “DIYRoot” app. After using a couple meal delivery services, I sussed out the kinds of recipe formulas they were mixing up each week, plus the items or equivalents I had found at nearby stores. Knowing that I could figure out the basic cooking, I made an app that listed as many recipes as I could find, broke them into components, let me add them to an erasable menu plan and shopping list, and even had some pictures.

The best version of an entry has an image, ingredients, and recipe. There’s a button to add it to the menu and all the items to a list.

Credit: Kevin Purdy

I didn’t quite master this app (the shopping list is plagued by blank items/rows), and it’s now technically an outdated “Classic” Glide app; maybe I’ll give it another shot. More successful is my most recent effort, “Pantry Items,” which is just a searchable list of spices and sauces, a note about how much I have left of each, and, through a webhook, add anything I see missing to a shopping list on Bring.

I can feel some people reading this article demanding that I just learn Swift or some mobile-friendly JavaScript package and make some real apps, but I steadfastly refuse. I enjoy the messy middle of programming, where I have just enough app, API, and logic knowledge to make something small for my friends and family that’s always accessible on this little computer I carry everywhere, but I have no ambitions to make it “real.” Anyone can add to it through the relatively simple spreadsheet. Heck, I’ll even take feature requests if I’m feeling gracious.

I use Glide, but you might have something else even simpler (and should recommend it as such in the comments). Just be warned that once you start thinking (or overthinking) along these lines, it can be hard to stop, even without the worldwide pandemic.

https://arstechnica.com/gadgets/2024/12/making-tiny-no-code-webapps-out-of-spreadsheets-is-a-weirdly-fulfilling-hobby/

Microsoft Windows AI is watching

In an era where many people already feel like they have no privacy due to tech encroachments, Microsoft dialed it up to an extreme degree in May. That’s when Microsoft unveiled a controversial Windows 11 feature called “Recall” that continuously captures screenshots of users’ PC activities every few seconds for later AI-powered search and retrieval. The feature, designed for new Copilot+ PCs using Qualcomm’s Snapdragon X Elite chips, promised to help users find past activities, including app usage, meeting content, and web browsing history.

While Microsoft emphasized that Recall would store encrypted snapshots locally and allow users to exclude specific apps or websites, the announcement raised immediate privacy concerns, as Ars senior technology reporter Andrew Cunningham covered. It also came with a technical toll, requiring significant hardware resources, including 256GB of storage space, with 25GB dedicated to storing approximately three months of user activity. After Microsoft pulled the initial test version due to public backlash, Recall later entered public preview in November with reportedly enhanced security measures. But secure spyware is still spyware—Recall, when enabled, still watches nearly everything you do on your computer and keeps a record of it.

Google Search told people to eat rocks

In May, Ars senior gaming reporter Kyle Orland (who assisted commendably with the AI beat throughout the year) covered Google’s newly launched AI Overview feature. It faced immediate criticism when users discovered that it frequently provided false and potentially dangerous information in its search result summaries. Among its most alarming responses, the system advised humans could safely consume rocks, incorrectly citing scientific sources about the geological diet of marine organisms. The system’s other errors included recommending nonexistent car maintenance products, suggesting unsafe food preparation techniques, and confusing historical figures who shared names.

The problems stemmed from several issues, including the AI treating joke posts as factual sources and misinterpreting context from original web content. But most of all, the system relies on web results as indicators of authority, which we called a flawed design. While Google defended the system, stating these errors occurred mainly with uncommon queries, a company spokesperson acknowledged they would use these “isolated examples” to refine their systems. But to this day, AI Overview still makes frequent mistakes.

https://arstechnica.com/ai/2024/12/2024-the-year-ai-drove-everyone-crazy/

The Raspberry Pi 5 inside its official case.

Credit: Andrew Cunningham

We read about Andrew’s experience with a pair of sub-$200 desktop PCs, but this story is what started it all. The spec sheet looked promising enough, with support for two 4K displays running at 60 Hz and space for an internal PCIe SSD, but the experience was not what he’d hoped.

Andrew’s time using the Raspberry Pi 5 as his daily driver started out disappointing, but once he reset his expectations, he ended up pleasantly surprised by the experience.

If you’re looking for the cheapest mini desktop PC possible, you’ll want to look elsewhere, but if you want to see how far along Arm Linux has come, read Andrew’s article.

The STS-51-B mission begins with the liftoff of the Challenger from Pad 39A in April 1985.

Credit: NASA

Being strapped into a small space and thundered into space aboard a giant rocket has to be an incredibly stressful experience. But sometimes the stress doesn’t end with a successful launch. We don’t often get to peer behind the curtains and get a glimpse of the mental state of an astronaut, so when we do, it’s jarring.

“Hey, if you guys don’t give me a chance to repair my instrument, I’m not going back,” said astronaut Taylor Wang during a Space Shuttle mission in 1985. The first Chinese-born person in space, Wang was heading up an experiment on the behavior of liquid droplets in microgravity. When it didn’t work at the outset, Wang asked permission to troubleshoot it and make repairs. When Mission Control denied his request, he uttered that chilling sentence.

Boeing’s Starliner spacecraft is lifted to be placed atop an Atlas V rocket for its first crewed launch.

Credit: United Launch Alliance

Not only has there been a lot of Boeing on this top 20 list, there has been a lot of Boeing in the news all year. And most of that news has been bad.

Eric Berger dives deep into the development of Starliner, outlining the problems and setbacks that plagued its development, trying to answer the big question of how a company like Boeing, which had been at the acme of crewed spaceflight for decades, fell so far behind competition that didn’t even exist 20 years ago?

Thank you for making Ars a daily read during 2024. May you and those you love have a happy and safe holiday season.

https://arstechnica.com/staff/2024/12/the-20-most-read-stories-of-2024-on-ars-technica/

Editor’s note: Warning: Although we’ve done our best to avoid spoiling anything too major, please note this list does include a few specific references to several of the listed films that some might consider spoiler-y.

This was the year that Marvel Studios hit the pause button on its deluge of blockbuster superhero movies, after rather saturating the market in recent years. It proved to be a smart move: the only Marvel theatrical release was the R-rated Deadpool & Wolverine, a refreshingly irreverent, very meta take on the genre that delighted audiences and lit up the global box office. Perhaps audiences aren’t so much bored with superhero movies as becoming more discriminating in their choices. Give us a fun, fresh take and we’ll flock back to theaters.

Fewer superhero franchise entries meant there was more breathing room for other fare. Horror in particular had a stellar year, with numerous noteworthy offerings, touching on body horror (The Substance), Satanic Panic (Late Night with the Devil), psychological horror (Heretic), hauntings (The Oddity), a rom-com/revenge mashup (Your Monster), an inventive reimagining of a classic silent film (Nosferatu), and one very bloodthirsty child vampire with a wicked sense of humor (Abigail). Throw in a smattering of especially strong sequels (Inside Out 2, Dune: Part 2), a solid prequel (Furiosa), and a few hidden gems, and we had one of the better years for film in recent memory.

As always, we’re opting for an unranked list, with the exception of our “year’s best” vote at the very end, so you might look over the variety of genres and options and possibly add surprises to your eventual watchlist. We invite you to head to the comments and add your favorite films released in 2024.

The Fall Guy

I love to mentally check out with a good movie when I fly. So, on a recent trip to New York City for Technicon, I settled into my narrow, definitely-not-my-couch airline seat and fell in love with The Fall Guy, a movie based on the TV show I remember watching as a teen back in the ’80s.

Directed by David Leitch (Deadpool 2, the John Wick franchise), The Fall Guy is pure entertainment—part rom-com, part action, funny as heck, and super meta. Leitch is perfectly suited to direct a film about a stuntman, having been one himself (he was Brad Pitt’s stunt-double five times). And the actors clearly are having a ton of fun roasting the industry, while also paying tribute to the invisible heroes of any movie: the stunt performers.

https://arstechnica.com/culture/2024/12/film-technica-our-favorite-movies-of-2024/

This means that the total computing power required for attention grows quadratically with the total number of tokens. Suppose a 10-token prompt requires 414,720 attention operations. Then:

• Processing a 100-token prompt will require 45.6 million attention operations.
• Processing a 1,000-token prompt will require 4.6 billion attention operations.
• Processing a 10,000-token prompt will require 460 billion attention operations.

This is probably why Google charges twice as much, per token, for Gemini 1.5 Pro once the context gets longer than 128,000 tokens. Generating token number 128,001 requires comparisons with all 128,000 previous tokens, making it significantly more expensive than producing the first or 10th or 100th token.

A lot of effort has been put into optimizing attention. One line of research has tried to squeeze maximum efficiency out of individual GPUs.

As we saw earlier, a modern GPU contains thousands of execution units. Before a GPU can start doing math, it must move data from slow shared memory (called high-bandwidth memory) to much faster memory inside a particular execution unit (called SRAM). Sometimes GPUs spend more time moving data around than performing calculations.

In a series of papers, Princeton computer scientist Tri Dao and several collaborators have developed FlashAttention, which calculates attention in a way that minimizes the number of these slow memory operations. Work like Dao’s has dramatically improved the performance of transformers on modern GPUs.

Another line of research has focused on efficiently scaling attention across multiple GPUs. One widely cited paper describes ring attention, which divides input tokens into blocks and assigns each block to a different GPU. It’s called ring attention because GPUs are organized into a conceptual ring, with each GPU passing data to its neighbor.

I once attended a ballroom dancing class where couples stood in a ring around the edge of the room. After each dance, women would stay where they were while men would rotate to the next woman. Over time, every man got a chance to dance with every woman. Ring attention works on the same principle. The “women” are query vectors (describing what each token is “looking for”) and the “men” are key vectors (describing the characteristics each token has). As the key vectors rotate through a sequence of GPUs, they get multiplied by every query vector in turn.

https://arstechnica.com/ai/2024/12/why-ai-language-models-choke-on-too-much-text/

As you crisscross the map, you also invariably stumble on a seemingly endless array of optional sidequests, mysteries, and “fieldwork,” which you keep track of in a dynamically updated journal. While there’s an attempt at a plot justification for each of these optional fetch quests, the ones I tried ended up being much less compelling than the main plot, which seems to have taken most of the writers’ attention.

As you explore, a tiny icon in the corner of the screen will also alert you to photo opportunities, which can unlock important bits of lore or context for puzzles. I thoroughly enjoyed these quick excuses to appreciate the game’s well-designed architecture and environments, even as it made Indy feel a bit more like a random tourist than a badass archaeologist hero.

Quick, hide!

Unfortunately, your ability to freely explore The Great Circle‘s environments is often hampered by large groups of roaming Nazi and/or fascist soldiers. Sometimes, you can put on a disguise to walk among them unseen, but even then, certain enemies can pick you out of the crowd, something that was not clear to me until I had already been plucked out of obscurity more than a few times.

When undisguised, you’ll spend a lot of time kneeling and sneaking silently just outside the soldiers’ vision cones or patiently waiting for them to move so you can sneak through a newly safe path. Remaining unseen also lets you silently take out enemies from behind, which includes pushing unsuspected enemy sentries off of ledges in a hilarious move that never, ever gets old.

When your sneaking skills fail you amid a large group of enemies, the best and easiest thing to do is immediately run and hide. For the most part, the enemies are incredibly inept in their inevitable pursuit; dodge around a couple of corners and hide in a dark alley and they’ll usually quickly lose track of you. While I appreciated that being spotted wasn’t an instant death sentence, the ease with which I could outsmart these soldiers made the sneaking a lot less tense.

https://arstechnica.com/gaming/2024/12/indiana-jones-and-the-great-circle-captures-the-feel-of-a-great-indy-movie/