Radically reinventing the Air Force won't win a future fight, its director for force design said.The Air Force has been analyzing and wargaming what it'll need to defeat a top adversary.The service is now prioritizing how to tailor systems for countering very specific threats.New fighter jets or bombers won't be enough to win the next war, the US Air Force director for force design, integration, and wargaming said this week.Instead, the service needs to focus on what specific threats top adversaries like China or Russia pose to Air Force operations to tailor solutions for defeating them.At a Hudson Institute event on Wednesday, Maj. Gen. Joseph Kunkel, who oversees force design for the Air Force, talked about how the service is evolving its capabilities and strategies at what other leaders have described as a critical time.Kunkel said that the Air Force has been on a decade-long journey to redesign and reinvent. That conversation started like this: "We probably just need to look at new fighters. We've always had fighters, so let's look at new fighters, and we've always had bombers, so let's look at new bombers."The US military has fielded new fighters, such as the Boeing F-15EX Eagle II and the Lockheed Martin F-35 Lightning II Joint Strike Fighter, and new bombers, like the Northrop Grumman B-21 Raider.But just upgrading to next-generation aircraft isn't enough to prepare the US Air Force and larger Joint Force for future warfare. "When we do the analysis," Kunkel said, "what we find is just reinventing the Air Force doesn't win."Instead, he said, combat success is more about integrating capabilities and systems together, using autonomy and all-domain sensing, for example. "Those are things that we're finding as game-changers," Kunkel said, because they address specific challenges to the force. US Air Force B-1B bombers, F-22 fighter jets, and South Korean Air Force F-35 fighter jets fly during a joint air drill at an undisclosed location in South Korea. South Korean Defense Ministry via Getty Images The problems facing the Air Force in a future fight could look similar to the fight in Ukraine today, where the skies are contested, with neither side being able to secure air superiority like what the US and its allies enjoyed in the Middle East.American adversaries are fielding their own next-gen fighters, and air and missile defense systems are becoming increasingly sophisticated, demanding more from pilots. And there are also growing missile threats, both in Europe and the Indo-Pacific, to bases the service relies on to conduct air operations.One of the Air Force's priorities in recent years has been Agile Combat Employment, which aims to boost survivability by having air assets operate from unconventional runways and outposts, thus complicating enemy targeting of US aircraft. Bases are fixed, but American adversaries can't target every piece of concrete, every road and highway.ACE has been a major focus as China has been building an intimidating missile force that could overwhelm US airfields and airpower in a missile strike. The Air Force is now building on this thinking, looking to ideas that go beyond new aircraft. US Air Force, US Marine Corps, Japan Air Self-Defense Force, and Royal Australian Air Force personnel participate in fueling operations during the Agile Combat Employment exercise at Andersen Air Force Base in Guam. US Air Force/Master Sgt. JT May III Kunkel said the Air Force's focus is on something it hadn't really done before: tailoring attributes for capabilities based on the threat. The first step, he said, is to define the threat and how it's impacting US Air Force operations.When the Air Force understands how potential enemies can pressure both air and ground missions, then it can determine what capabilities it needs to counter specific threats and deliver more than just an upgraded aircraft. Instead, it brings a targeted response.The Air Force has faced tough questions about generating readiness and maintaining overmatch in a time of great-power competition. And last year, the service announced widespread changes in its focuses, more specifically in how it trains its airmen and develops capabilities needed for various threats.At the time, then-Air Force Secretary Frank Kendall said the service was "moving forward with a sense of urgency to ensure we are ready to deter and, if necessary, win."

The Logoff is a daily newsletter that helps you stay informed about the Trump administration without letting political news take over your life. Subscribe here.Welcome to The Logoff. Today Im focused on Donald Trumps mixed messages on the fate of Medicaid, the low-income health insurance program that more than 70 million Americans depend on.Whats the latest? Trump said today that Republicans wouldnt touch Medicaid, Medicare, or Social Security in their legislation to slash taxes and government spending, but he hedged by saying they would look for fraud.Trump says a lot of things. Why does this matter now? Because House Republicans passed a bill on Tuesday that calls for $2 trillion in spending cuts over 10 years. The bill asks the committee that oversees Medicaid and Medicare to identify $880 billion in savings. Given that Medicare (health care for seniors) is politically untouchable, that sounds like a call for steep cuts to Medicaid.Why focus on fraud? Republicans have been reluctant to propose structural changes to Medicaid, as its unpopular to take away health insurance from people who need it particularly while cutting taxes for the wealthy. Instead, Trump and other top GOP officials have pledged to root out fraud. Thats more politically palatable, but the math doesnt work. Theres simply not enough fraud in the system to get anywhere near the scope of savings Republicans are looking for.Whats next? Are Medicaid cuts coming? Its way too soon to know. This House bill only sets overall numbers for tax and spending cuts. GOP lawmakers still have to craft a separate bill that lays out what specific programs should get cut. If Medicaid cuts make it into that bill, then its a sign the program is on the chopping block.But even then, it wouldnt be certain that the cuts would ever become law. Republicans have only a tiny majority in the House; they have to find something basically their entire caucus can agree on. In short, if even a handful of Republicans balk at cutting Medicaid, the low-income health insurance program could emerge unscathed.And with that, its time to log off Its 62 degrees right now in DC, so if youre there, I cannot recommend anything online thats going to match the psychic value of going outside. If the weather is not as nice where you are, my heartfelt condolences. As a consolation prize, heres a lovely essay about, well, being at peace with yourself, imperfect though we all are. Take good care today. See you back here tomorrow.See More:

After a dramatic week that saw both the third anniversary of the war in Ukraine and an unprecedented flurry of diplomatic activity, its becoming possible to see what a real if far from ideal agreement to end the bloody conflict might look like. But to know whether an agreement is actually achievable or realistic would require being inside the heads of two of the most inscrutable men on the planet: Donald Trump and Vladimir Putin. This week, Washington and Kyiv reached a deal to exploit Ukraines mineral resources. A plan emerged for a potential European peacekeeping force to be deployed to Ukraine after the war is over. And a visit to Washington by Ukrainian President Volodymyr Zelenskyy is imminent. Both developments suggest Ukraine and European countries are working to make the best of a situation where the US can no longer be counted on to be on Ukraines side. Can minerals save the US-Ukraine relationship? Last week, relations between the US and Ukraine seemed to have reached a nadir.The US dispatched senior negotiators to meet their Russian counterparts in Saudi Arabia without Ukraine present breaking a longstanding promise. The US tried to get Zelenskyy to sign over half of Ukraines critical minerals as reimbursement for past American support. Trump referred to Zelenskyy as a dictator for not holding elections during wartime. (He later declined to apply the same description to Putin.)Then, on Monday, signs of a major pro-Russian shift continued: The US twice sided with Russia over Ukraine and its European allies at the United Nations. First, the US voted to oppose a resolution in the general assembly that condemned Russias invasion. Then it supported a resolution in the security council that called for an end to the conflict but contained no criticism of Russia. But then, on Tuesday, the US and Ukraine signed a revised version of the long-promised minerals deal. Zelenskyy will travel to the US on Friday to sign the agreement. Ukraine is believed to have significant reserves of critical minerals like lithium and graphite, as well as rare earth metals, such as scandium and neodymium. China currently dominates the supply chains for these minerals, which have a variety of high-tech applications. (Some analysts are skeptical that Ukraines reserves are really as large as is being advertised.) A significant amount of these reserves are believed to be in territory currently occupied by Russia, and Putin was quick to say this week that he would also be open to a partnership with the US to develop them. Before Trump took office, Ukrainian officials hoped to leverage the countrys mineral wealth to ensure future US support. This was not an unreasonable plan, given Trumps interest in controlling mineral-rich territories like Greenland, but it appears to have backfired. Rather than an enticement for future support, Trump viewed Ukraines resources as payback for past US aid. (Trump has repeatedly claimed the US has provided Ukraine with $300 billion or $350 billion in aid. Independent estimates put the real number at around $120 billion.)Two weeks ago, Treasury Secretary Scott Bessent reportedly presented Zelenskyy with a deal that included a demand that Ukraine turn over 50 percent of revenue from future mineral extraction to the US, up to $500 billion. Bessent demanded that Zelenskyy sign immediately without consultations. It was Zelenskyys refusal to sign that led to Trumps public sniping at the Ukrainian leader. On Tuesday, Ukraine and the US agreed to a new version of the deal that drops this requirement and instead establishes a joint fund for the management of those resources. Officials say this is only a framework agreement and no money is actually changing hands. (Some analysts are skeptical any ever will.) The deal also, which seems crafted to be deliberately vague, critically, does not include any security guarantees or pledges of future military aid. But Ukrainian officials are hopeful it will put them in a stronger negotiating position with the Trump administration going forward, and improve the tenor of the relationship after last weeks sniping. Can Europe keep the peace?The British and French are promoting a plan for a European reassurance force to be deployed to Ukraine. French President Emmanuel Macron, currently the European leader with the most experience dealing with Trump, visited the White House on Monday for talks on Ukraine with Trump. British Prime Minister Keir Starmer will follow suit on Thursday. Whether the reassurance force is actually reassuring to anyone may depend on how much risk of a wider conflict Ukraines partners are now willing to take.The plan, which is still being developed, would likely involve less than 30,000 troops from several European countries and focus on air and maritime power. Its unlikely to impress the Russians numerically: At this point, Ukraine already has the largest and most experienced ground forces in Europe. But the idea is that Russia might think twice about violating a ceasefire if, by doing so, they risked direct conflict with western militaries. The US is supportive of the idea of a European peacekeeping force. Britain and France insist, however, that the force would have to come with a US backstop. What that means hasnt been fully defined, but it likely would mean they would want the US to provide air support if the troops came under attack.Secretary of Defense Pete Hegseth seemed to rule out a US role in the peacekeeping force in his recent speech to the Munich Security Conference. But when Trump was asked by reporters about US backing for the force following his meeting with Macron, he didnt entirely dismiss the idea: Were going to have a backing of some kind and obviously, the European countries are going to be involved and I dont think youre going to need much backing. I think thats not going to be a problem. Once an agreement is signed, Russia is going to get back to its business and Ukraine and Europe are going to get back to their business. Trump also said he had been personally told by Putin that the Russian leader would be willing to accept European peacekeepers in Ukraine after the war a claim the Russian government quickly denied. Not everyone is on board with the plan. The German and Polish governments are skeptical; Zelenskyy has said a force of 100,000 to 150,000 troops backed by the US would be required. But given that these troops are envisioned less as an actual military deterrent than as a tripwire, the key question is not how many of them there will be its what the countries sending them will do if they get attacked.Since the beginning of the war, Ukraines backers including both the Europeans and the US have had two priorities: assisting the Ukrainians in fighting the Russians, and preventing a wider war between Russia and its nuclear armed adversaries in the West. The second priority has often outweighed the first. (Theres such involvement from other countries and it could really lead to a very big war, World War III, and were not going to let that happen either, Trump said on Monday.) Whether the reassurance force is actually reassuring to anyone may depend on how much risk of a wider conflict Ukraines partners are now willing to take.A potential deal is emerging. Does anyone want it?An agreement that freezes the current front line in place, and includes a European peacekeeping force with some level of US support, might be hard for Ukraine to turn down. Leaving territory under Russian occupation would be a painful sacrifice, but polls show most Ukrainians now favor negotiations to end the war rather than fighting on until victoryStill, Ukrainian officials are inherently skeptical of agreements with Russia, arguing that Moscow violated previous agreements to respect their sovereignty in 1994 and 2014. Ukraine had hoped for NATO membership or NATO-lite security guarantees from the US: assurance that, if they were attacked again, the US would join the fight. Those now appear to be off the table. Some have suggested the US and Ukraine could instead pursue an Israel model partnership: The US is not bound by law to come to Israels defense, but it is required to provide Israel with military capabilities to maintain its qualitative military edge over its rivals.The fear, as always, is that a ceasefire will simply give Russia time to regroup for another attack, this one aimed at snuffing out Ukraines political independence entirely. Ukraine, of course, could reject a US-backed deal, and continue to fight on, but that might mean doing without US military systems like Patriot air defense systems, HIMARS rocket launchers, and Elon Musks Starlink satellite system, which have been critical to their war effort. All of this, of course, assumes that Putin is actually interested in ending the war. Russian officials, like Foreign Minister Sergey Lavrov, insist they are not interested in a quick deal and will keep fighting until Ukraines political drift toward the West in recent years and NATOs involvement in Eastern Europe are addressed. Given the existential stakes Putin has attached to this war, analysts are skeptical Russia would be willing to stop fighting on terms that would be acceptable even to this administration. Still, there are signs that Russias offensive momentum on the ground in Ukraine has slowed, that it is taking heavy casualties and losing equipment, is having difficulties recruiting new troops, and that its economy is showing signs of strain. There are reasons for Russia to quit while its ahead. The Washington-based think tank Institute for the Study of War noted one recent concession from Moscow: In a recent interview, Putin seemed to acknowledge that Zelenskyy would be Russias future negotiating partner. Russia had previously maintained that Zelenskyy was not a legitimate leader because Ukraine did not hold elections in 2024. Still, Russia could participate in talks with the aim of dragging them out indefinitely and pressing its advantage on the battlefield. With a new US administration aping Kremlin talking points to an extent even the Russians seem to find baffling, Putin may see this as a time not to settle but to see what more he can get. Trump had said prior to taking office that he was willing to increase aid to Ukraine in order to get Russia to agree to a deal. Its unclear whether that possibility is still on the table or what Trump will do if a ceasefire isnt reached soon. For weeks, Ukrainian and European officials thought they understood the administrations approach, only for Trump to completely flip the script following a phone call with Putin this month. Its not out of the question it could flip again.See More:

Christopher Reeve will forever be the definitive live-action Superman, even as other performers (up next: David Corenswet in James Gunns DC Studios release) have assumed the mantle on the big and small screen. But while Reeve always delivered suitably superheroic performancesand/or adorably awkward, while in Clark Kent modenot every Superman movie he starred in was a masterpiece. Or even, frankly, all that great. Lookin at you, Superman III. io9s Germain Lussier recently dug into why Superman III is the worst among Reeves Man of Steel outingsyep, its the one where Richard Pryor helps turn Superman into an evil version of Superman using fake Kryptonite, and is to put it bluntly, a huge piece of shit. However, a Superman suit worn by Reeve is still a top-flight item for collectors, and the Evil Superman get-up from Superman III is a curiosity unto itself. Propstore has it featured in an upcoming auction, and you can understand why its estimated to go for $200,000-$400,000, with a starting bid of $100,000 just to get your foot in the door. Even Propstores description of the movie sounds satirical, which it unfortunately is not: [In] Richard Lesters superhero sequel Superman III. Superman wore his darker-colored costume after he was exposed to Kryptonite by Gus Gorman (Richard Pryor), when he was corrupted and turned into evil Superman. Superman then proceeded to cause mischief, including straightening the Leaning Tower of Pisa, before drinking heavily in a bar and then fighting a weak Clark Kent in a junkyard. It comes with the following: a custom blue knit leotard with the stylized Superman logo sewn into the front with attached maroon trunks, a pair of matching knit tights, a cape, a belt, and a pair of boots. It is darker in color to highlight Supermans newly corrupted nature. Propstore The auction house further notes that full costumes are scarce, making this a rare opportunity to own an iconic piece of superhero history; in 2022, People reported that Propstore had sold a complete Superman costume worn by Reeve across the first three Superman movies; it was in fantastic condition and fetched $359,375.The Evil Superman costume Reeve donned in 1983s Superman IIIalso looks to be in good condition; though theres been some fading of its all-important darker color, Propstore notes that professional costume conservators [do] believe that color restoration is feasible, pending further fabric tests. If you have piles of spare cash lying around, and a fascination with heroes gone bad (then, inevitably, back to good again), bidding on the costume ends March 26. Learn more on Propstores site here. Want more io9 news? Check out when to expect the latest Marvel, Star Wars, and Star Trek releases, whats next for the DC Universe on film and TV, and everything you need to know about the future of Doctor Who.

By AJ Dellinger Published February 26, 2025 | Comments (0) | Google demonstration of its updated Results About You tool showing how to request removal of a result Google If you ever Google yourself and dont like what you see, you have some recourse. Googles Results About You tool, which it first introduced in 2022, just got an update that makes it easier for you to request the removal of search results that contain your personal information, including outdated search results that are no longer relevant to you. The update introduces a new hub that will show you any results related to you that might pop up online. (Youll have to sign up to opt into this feature, but once you do, Google says it will proactively monitor search results for you and put any relevant results in the hub for your review.) Additionally, Google is adding the ability to request a result be removed when people search for you. Tap the three dots next to a search result and a new menu option, Remove this result will appear. Youll have to select a reason for the removal (shows personal information that you dont want published, is out of date, you have a legal reason for wanting it taken down) and Google will review the request and take down the result if it meets the necessary qualifications. You can also request Google recrawl websites to get up-to-date information about you. You can think of Googles Results About You as a sort of compromise between the companys desire to collect and share every detail imaginable and the general publics growing desire for privacy. Its not a legal right, the way the European Unions Right to Be Forgotten laws are, but its an option for clawing back a little bit of your information that you might not want to be publishedas long as Google agrees with your request. If youd like to opt-in to Googles active web monitoring for your personal information and request removals, youll have to sign up for Results About You. In order to do that: Sign into your Google account Select Manage your Google Account Select Data & privacy Open My activity and select Other Activity Scroll down to Results about you and tap or click Manage results about you From here, youll be able to set up your Result About You settings, including any names youd like to monitor (including nicknames and maiden names), as well as phone numbers, addresses, and email addresses that might be associated with you. You can then set up notifications so you can choose how frequently Google updates you on results that contain your information. Once youre signed up, youll be able to access any results about yourself from the same dashboard. Remember, Google will be able to decline any of your requests if it decides that the information is considered valuable to the public. But it never hurts to ask. In this case, its about all you can do.Daily NewsletterYou May Also Like By Kyle Barr Published February 26, 2025 By Thomas Maxwell Published February 25, 2025 By Kyle Barr Updated February 14, 2025 By AJ Dellinger Published February 13, 2025 By Florence Ion Published February 11, 2025 By Florence Ion Published February 11, 2025

Complex teeth with multiple cusps in an African cichlid fish. The cichlid fish of Africa's Great Lakes have formed new species more rapidly than any other group of vertebrates. A new study shows that the ease with which these fish can develop a biological innovation (complex teeth), not just the innovation itself, enables this rapid evolution. (Credit: Nick Peoples, UC Davis)NewsletterSign up for our email newsletter for the latest science newsFor certain fishes, evolution is easy. After tracking the evolution of teeth in cichlid fishes from Africa, a team of researchers has found that these fishes have developed the ability to evolve rapidly, allowing them to adapt their teeth readily for different habitats and diets. This ability, the researchers report today in a study in Nature, helps these fishes split off into new species faster than any other fishes and, for that matter, any other vertebrates.This changes the way we think about key innovations, said Nick Peoples, a study author and a graduate student at the University of California, Davis Department of Evolution and Ecology, according to a press release. Indeed, the findings indicate that the ease of evolutionary innovation is as important in driving speciation as an evolutionary innovation is itself, speeding the development of new species in easily evolving lineages.Teeth TransitionsAmong the fishes, there are a few options for teeth: Some fish sport simple conical teeth, while others sport complex cusped teeth. These differences allow them to survive in distinct habitats and on distinct diets. But African cichlids are famous for making the most of these two types of chompers, taking on more distinct habitats and more distinct diets than most other fish species. A surprisingly large lineage, African cichlids are adaptable, some studded with cones and some studded with cusps that allow them to pierce and tear through algae, plants, and prey, and it is these variations in teeth that are thought to fuel their adaptability. Setting out to explore the evolution of these toothy variations, Peoples studied the teeth of 30,000 fish species, including 1,000 African cichlid species, for two years. Tracing their evolutionary history, he tracked their transitions from simple to complex teeth.He found that teeth evolved from simple to complex around 86 times across all fish species and that these transitions were common in African cichlids, which adapted with a certain ease of evolution. In fact, in addition to switching from simple to complex, the teeth of these fishes also transitioned from complex to simple, all at an impressive evolutionary pace.Read More: How Does Speciation Drive Evolution?Evolutionary EasePeoples and his team thus concluded that African cichlids ability to easily evolve their teeth, from simple to complex and back, was an evolutionary advantage all on its own, allowing the fish to adapt to different habitats and diets.Its not just the teeth, its how quickly they are gained or lost, Peoples said in the release. Retaining the genetic requirements for cones and cusps alike, these fish are able to transition between the two teeth types much more rapidly. According to the researchers, this ease of evolution allows African cichlids to churn out new species much more readily than any other vertebrates. Indeed, African cichlids are famous for their rapid speciation, as scientists have described some 1,700 species and are continuing to discover more. (Of these, many are found only in a single lake, like Lake Victoria or Lake Malawi, which both support over 500 species of cichlids).The researchers say that their finding that evolutionary ease is itself an innovation that fosters speciation is not limited to African cichlids. It isnt even limited to fish. There are plenty of other lineages that are famous for their diversity, and further investigation may find that evolution, at least for a specific trait like teeth, is easy for those lineages, too.Read More: How Do We Define A Species?Article SourcesOur writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:Sam Walters is a journalist covering archaeology, paleontology, ecology, and evolution for Discover, along with an assortment of other topics. Before joining the Discover team as an assistant editor in 2022, Sam studied journalism at Northwestern University in Evanston, Illinois.1 free article leftWant More? Get unlimited access for as low as $1.99/monthSubscribeAlready a subscriber?Register or Log In1 free articleSubscribeWant more?Keep reading for as low as $1.99!SubscribeAlready a subscriber?Register or Log In

In the late 80s, a team of Soviet and West African archaeologists discovered an African rainforest site that had the potential to rewrite at least a chapter of human evolutionary history. Artifacts encased in several layers of sediment hinted that some early humans had settled and thrived there, during a time when it was thought that they evolved primarily on savannas. Almost nobody paid attention.There were three reasons. First, the group published its findings in Russian, which relatively few scientists outside the Soviet Union could read. Second, West Africa was then not considered a major scene in human evolution. And third, the team lacked the technological tools to accurately date the tools, plant remains, and layers of dirt.Over 30 years later, a new group guided by one of the original team members returned. This time they showed humans had lived in this rainforest about 150,000 years ago, according to an article in Nature. Thats nearly 10 times longer than previous evidence for African rainforest occupation, and more than twice as long as the next most recent human rainforest habitat globally, found in Southeast Asia.Multiple Habitats for Early HumansThe implications go deeper than just changing some dates. The finding lends credence to a theory that humans were evolving in multiple, diverse habitats at the same time.Knowing that groups of hunter-gatherers already lived in radically different habitats and ecosystems this far back tells us that ecosystem diversification lies close to the root of our species, and that this ability probably modulated patterns of contact and genetic exchanges between different groups of people, says Eleanor Scerri, a professor at the Max Planck Institute of Geoanthropology and an author of the study.Scerri has long rejected the idea that humans emerged from a single population and region. She had a hunch that human evolution wasnt just what she calls a Savanah Process. Picking this particular site allowed her to address two hypotheses.The Anyama SiteTwo key factors made the Anyama site a perfect natural laboratory. First, climate data and models indicated that the area had always been a rainforest. Second, the earlier excavation revealed the site to be deeply stratified in other words, many layers of soil held a variety of clues about how the area was lived in over time.It also didnt hurt that much of the digging had already been done, and that one of the trenchs original excavators Francois Yod Gud, a West African archeologist could lead them to it. The original trench was easily visible once we were taken to the location by Professor Gud, says Scerri,. That said, their excavation and sedimentological work was so good, our work almost feels like an extension of theirs, a final chapter, so to speak. Humans in the Rain ForestOnce there, along with stone tools, they found numerous pieces of plants and stones in layers representing different time periods. They were fortunate that the trench had already been dug and only needed minimal work to extract samples, because as soon as they arrived, they realized they were in a race against time.The field team had arrived at the site just as the COVID-19 pandemic was spreading and had to evacuate within a week. They secured as many samples as they could and scrambled to formulate a plan to get out. They were on the last flight out of Abidjan before the airport shut down, says Scerri. The site was subsequently destroyed before we could get back to it. Being able to close the sites story with such aplomb is a gift, given the circumstances.Article SourcesOur writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:Before joining Discover Magazine, Paul Smaglik spent over 20 years as a science journalist, specializing in U.S. life science policy and global scientific career issues. He began his career in newspapers, but switched to scientific magazines. His work has appeared in publications including Science News, Science, Nature, and Scientific American.

Nature, Published online: 26 February 2025; doi:10.1038/d41586-025-00300-2A system of ocean currents called the Atlantic meridional overturning circulation strongly affects climate, but is showing signs of shutting down. An analysis now suggests that total collapse is unlikely this century.

Nature, Published online: 26 February 2025; doi:10.1038/d41586-025-00541-1Why are some species more likely to diversify than others? For the largest group of vertebrates, ray-finned fishes, the ability to evolve by transitioning back and forth between simple and complex teeth fuelled their diversification.

A study of the inner ear bones of Neanderthals shows a significant loss of diversity in their shape around 110,000 years ago, suggesting a genetic bottleneck that contributed to Neanderthals' decline.