The Brazilian Amazon experienced its smallest amount of yearly deforestation in nearly a decade, President Luiz Inacio Lula da Silva's government reported Wednesday, in line with its promise to combat forest loss.
Deforestation fell by 30.6 percent in the year-to-year period beginning in August 2023, according to the National Institute for Space Research (INPE).
During that time, 6,288 square kilometers (2,427 square miles) of forest were destroyed, which INPE Director Gilvan Oliveira said was "the lowest result in the last nine years."
Over the last century, the Amazon rainforest -- which covers nearly 40 percent of South America -- has lost about 20 percent of its area to deforestation, due to the spread of agriculture and cattle ranching, logging and mining, and urban sprawl.
Scientists warn that continued deforestation will put the Amazon on track to reach a point where it will emit more carbon than it absorbs, accelerating climate change.
Lula has pledged to put a stop to illegal deforestation in the Amazon by 2030 but faces an uphill battle against vested interests.
In addition to the Amazon, destruction of the Cerrado, the most species-rich savanna in the world, which is located in central Brazil, was reduced by 25.7 percent or 8,174 square kilometers, INPE reported.
The two different biomes were recently hit by historic drought and the subsequent spread of wildfires.
Mariana Napolitano, strategy director for the World Wildlife Fund in Brazil, called the latest data "good news" but stressed there was more work to be done.
"We need to reforest part of what was destroyed in recent decades, especially in the Amazon's case, which is approaching the point of no return -- losing its capacity to regenerate," she warned.
Environment Minister Marina Silva welcomed the "significant drop" as a part of Brazil's push to reduce carbon emissions, just days before participating in the COP29 UN climate conference in Baku, Azerbaijan.
"This reduction is the result of a new understanding that we are making in state politics... in the context that the problem of climate change is already an overwhelming reality in Brazil," she said.
Climate Observatory, a group of environmental NGOs, said in a release that "the numbers are a triumph for the country and a victory for Lula."
Deforestation dramatically worsened under Lula's far-right predecessor Jair Bolsonaro, whose administration saw Amazon deforestation shoot up 75 percent compared to the average of the previous decade.
Bangladesh is struggling to tamp down a surge in dengue cases as climate change turns the disease into a year-round crisis, leaving some pediatric wards packed with children squeezed two to a bed.
The Aedes mosquito that spreads dengue -- identifiable by its black and white striped legs -- breeds in stagnant pools, and cases once slowed after the monsoon rains faded.
"Normally, around this time, we would expect the flow of patients to ebb," said Fazlul Haque, walking through a ward crowded with dengue patients at Dhaka's Shaheed Sohrawardi Medical College.
"For the last three weeks, the number of dengue cases has been increasing".
"We get dengue patients almost every month," said Sabina Tabassum Anika, the doctor running the children's dengue ward.
"With cases higher than previous months, we're assigning two children to each hospital bed to accommodate them."
Last month, Bangladesh recorded 134 deaths from dengue, the deadliest month this year, taking the total in 2024 to 326.
Cases are lower than last year, when more than 1,000 died, but dengue deaths are now being recorded nearly every month, medics say.
More than 65,000 cases had been recorded at the start of November. Severe cases can trigger bleeding, internally or from the mouth and nose.
The World Health Organization has warned of the "alarming" spread of the virus, with reported cases worldwide approximately doubling each year since 2021.
More than 12.3 million cases, including more than 7,900 deaths, were reported in the first eight months of 2024.
Sheikh Daud Adnan, from the Communicable Disease Control (CDC), said efforts should be made to destroy larval sites.
"Too often, we delay and act only after an outbreak", Adnan said.
"People still don't fully believe that dengue can strike any time of the year, often mistaking it for a seasonal fever."
MSNBC's political reporter Vaughn Hillyard challenged Robert F. Kennedy Jr. Tuesday after he claimed that he didn't want to eliminate vaccines.
Kennedy has spent years opposing vaccines, according to many reports. But when he spoke to Hillyard, he promised to ensure they were accessible to anyone who wanted them.
As FactCheck.org wrote, "Kennedy insists he’s not ‘anti-vaccine,’ but many of his debunked arguments are straight from the anti-vaccine playbook, which he and his nonprofit have helped write.”
Trump announced during a Nevada rally last week that Kennedy was "going to work on health and women's health."
"Would that include COVID vaccines that are currently on the market?" asked the reporter.
Kenndy hedged, saying he wanted the "best science" for vaccines, and Hillyard seized on the moment.
"As part of that, during the pandemic, the height of the pandemic, you were questioning the FDA and calling them out for approving the emergency authorization of the COVID vaccines. If you had been in charge of the FDA at that time, would you have blocked the authorization of the COVID vaccines?"
Kennedy claimed that he argued that vaccines wouldn't stop transmission.
"They were saying you need to take this vaccine in order to protect. I knew in May 2020 that the vaccines were not going to protect against transmission. I was reading the studies," Kennedy said.
The government had claimed that the vaccine would lessen the severity of the illness if transmitted and reduce the number of people dying in hospitals.
Hillyard challenged whether RFK would have allowed the vaccine, and Kenndy dodged again, saying he would have been "honest."
"You wouldn't have blocked it?" Hillyard hammered.
"I wouldn't directly block it," Kennedy said. "I would have made sure we had the best science. There was no effort to do that at that time."
So Hillyard asked why the American people should have confidence that he would ensure a vaccine was available in the future in a similar situation. He also grilled Kennedy on which agencies he would eliminate, a question that comes from the politician's campaign pledge to close down the Food and Drug Administration and Centers for Disease Control.
Former left-wing conspiracy theorist turned Trump ally Robert F. Kennedy Jr. has big plans now that the twice-impeached former president is now heading back to the White House.
NPR's Steve Inskeep reports that Kennedy told him during an interview on Wednesday that the new Trump administration "will recommend getting fluoride out of drinking water" and will also provide consumers with more "information" about vaccines.
Kennedy has for decades pushed baseless theories linking vaccines to autism, despite the fact that multiple studies have found no such link.
According to the Mayo Clinic, "a small study in 1998 suggested a link between vaccinations and autism spectrum disorder," although "the study was reviewed further and retracted" and "the author's medical license was revoked due to falsified information."
Additionally, fluoridation of water has been credited with vastly reducing cavities in children.
Kennedy was long a fringe figure in Democratic politics who pushed false conspiracy theories about former President George W. Bush stealing the 2004 election from rival John Kerry.
On Nov. 9, 2024, the world will mark Carl Sagan’s 90th birthday – but sadly without Sagan, who died in 1996 at the age of 62.
Most people remember him as the co-creator and host of the 1980 “Cosmos” television series, watched worldwide by hundreds of millions of people. Others read “Contact,” his best-selling science fiction novel, or “The Dragons of Eden,” his Pulitzer Prize-winning nonfiction book. Millions more saw him popularize astronomy on “The Tonight Show.”
What most people don’t know about Sagan, and what has been somewhat obscured by his fame, is the far-reaching impact of his science, which resonates to this day. Sagan was an unequaled science communicator, astute advocate and prolific writer. But he was also an outstanding scientist.
Sagan propelled science forward in at least three important ways. He produced notable results and insights described in over 600 scientific papers. He enabled new scientific disciplines to flourish. And he inspired multiple generations of scientists. As a planetary astronomer, I believe such a combination of talents and accomplishments is rare and may occur only once in my lifetime.
Scientific accomplishments
Very little was known in the 1960s about Venus. Sagan investigated how the greenhouse effect in its carbon dioxide atmosphere might explain the unbearably high temperature on Venus – approximately 870 degrees Fahrenheit (465 degrees Celsius). His research remains a cautionary tale about the dangers of fossil fuel emissions here on Earth.
Sagan proposed a compelling explanation for seasonal changes in the brightness of Mars, which had been incorrectly attributed to vegetation or volcanic activity. Wind-blown dust was responsible for the mysterious variations, he explained.
Sagan and his students studied how changes to the reflectivity of Earth’s surface and atmosphere affect our climate. They considered how the detonation of nuclear bombs could inject so much soot into the atmosphere that it would lead to a yearslong period of substantial cooling, a phenomenon known as nuclear winter.
With unusual breadth in astronomy, physics, chemistry and biology, Sagan pushed forward the nascent discipline of astrobiology – the study of life in the universe.
Together with the research scientist Bishun Khare at Cornell University, Sagan conducted pioneering laboratory experiments and showed that certain ingredients of prebiotic chemistry, called tholins, and certain building blocks of life, known as amino acids, form naturally in laboratory environments that mimic planetary settings.
Carl Sagan proposed the ‘Golden Record,’ which features the sounds of Earth, including greetings spoken in 55 languages. NASA via Wikimedia Commons
His passion for finding life elsewhere extended far beyond the solar system. He was a champion of the search for extraterrestrial intelligence, also known as SETI. He helped fund and participated in a systematic search for extraterrestrial radio beacons by scanning 70% of the sky with the physicist and electrical engineer Paul Horowitz.
But perhaps his most important gift to society was his promotion of truth-seeking and critical thinking. He encouraged people to muster the humility and discipline to confront their most cherished beliefs – and to rely on evidence to obtain a more accurate view of the world. His most cited book, “The Demon-Haunted World: Science as a Candle in the Dark,” is a precious resource for anyone trying to navigate this age of disinformation.
Impact
A scientist’s impact can sometimes be gauged by the number of times their scholarly work is cited by other scientists. According to Sagan’s Google Scholar page, his work continues to accumulate more than 1,000 citations per year.
Indeed, his current citation rate exceeds that of many members of the National Academy of Sciences, who are “elected by their peers for outstanding contributions to research,” according to the academy’s website, and is “one of the highest honors a scientist can receive.”
Sagan was nominated for election into the academy during the 1991-1992 cycle, but his nomination was challenged at the annual meeting; more than one-third of the members voted to keep him out, which doomed his admission. An observer at that meeting wrote to Sagan, “It is the worst of human frailties that keeps you out: jealousy.” This belief was affirmed by others in attendance. In my opinion, the academy’s failure to admit Sagan remains an enduring stain on the organization.
No amount of jealousy can diminish Sagan’s profound and wide-ranging legacy. In addition to his scientific accomplishments, Sagan has inspired generations of scientists and brought an appreciation of science to countless nonscientists. He has demonstrated what is possible in the realms of science, communication and advocacy. Those accomplishments required truth-seeking, hard work and self-improvement. On the 90th anniversary of Sagan’s birth, a renewed commitment to these values would honor his memory.
How did everything begin? It’s a question that humans have pondered for thousands of years. Over the last century or so, science has homed in on an answer: the Big Bang.
This describes how the Universe was born in a cataclysmic explosion almost 14 billion years ago. In a tiny fraction of a second, the observable universe grew by the equivalent of a bacterium expanding to the size of the Milky Way. The early universe was extraordinarily hot and extremely dense. But how do we know this happened?
Let’s look first at the evidence. In 1929, the American astronomer Edwin Hubble discovered that distant galaxies are moving away from each other, leading to the realisation that the universe is expanding. If we were to wind the clock back to the birth of the cosmos, the expansion would reverse and the galaxies would fall on top of each other 14 billion years ago. This age agrees nicely with the ages of the oldestastronomical objects we observe.
The idea was initially met with scepticism – and it was actually a sceptic, the English astronomer Fred Hoyle, who coined the name. Hoyle sarcastically dismissed the hypothesis as a “Big Bang” during an interview with BBC radio on March 28 1949.
This is article is part of our series Cosmology in crisis? which uncovers the greatest problems facing cosmologists today – and discusses the implications of solving them.
The world's first wooden satellite has blasted off on a SpaceX rocket, its Japanese developers said Tuesday, part of a resupply mission to the International Space Station.
Scientists at Kyoto University expect the wooden material to burn up when the device re-enters the atmosphere -- potentially providing a way to avoid generating metal particles when a retired satellite returns to Earth.
These particles may negatively impact both the environment and telecommunications, the developers say.
Each side of the box-like experimental satellite, named LignoSat, measures just 10 centimeters (four inches).
It was launched on an unmanned rocket from NASA's Kennedy Space Center in Florida, Kyoto University's Human Spaceology Center said.
The satellite, installed in a special container prepared by the Japan Aerospace Exploration Agency, "flew into space safely", it said in a post on X.
A spokeswoman for LignoSat's co-developer Sumitomo Forestry told AFP the launch had been "successful".
It "will arrive at the ISS soon, and will be released to outer space about a month later" to test its strength and durability, she said.
Data will be sent from the satellite to researchers who can check for signs of strain and determine if the satellite can withstand extreme changes in temperature.
"Satellites that are not made of metal should become mainstream," Takao Doi, an astronaut and special professor at Kyoto University, said at a press conference earlier this year.
Someone following the 2024 presidential election could have seen the following two videos on social media. One shows a man holding a bin full of mail-in ballots entering a building. The other, from before Joe Biden withdrew from the race and labeled “Migrants talk about 2024 election,” shows a man interviewing several people in Spanish, all of whom answer that they plan to vote for Biden.
These videos purport to show different types of illegal election activity: ballot harvesting and noncitizen voting. Both videos are real, not AI-generated, and both show real people behaving authentically, not acting. They also do not show the events they claim to represent.
The first shows a postal worker delivering mailed-in ballots to an election center; the second is deceptively edited to falsely imply that the interviewees were stating their intentions to vote rather than whom they would vote for if they were eligible to vote.
Cheap but effective fakes
Recent headlines warn of sophisticated, AI-driven deepfakes. But it is low-tech cheap fakes like these that fuel the latest round of disinformation. Cheap fakes are the Swiss army knife in the propagandist’s tool belt. Changing a date, altering a location or even repurposing a clip from a video game and passing it off as battlefield combat require little know-how yet effectively sow confusion.
The good news is that you can avoid being taken in by these ruses – not by examining the evidence closely, which is liable to mislead you, but by waiting until trusted sources verify what you’re looking at. This is often hard to do, however.
In the largest survey of its kind, 3,446 high school students evaluated a video on social media that purported to show election fraud in the 2016 Democratic primary. Students could view the whole video, part of it or leave the footage to search the internet for information about it. Typing a few keywords into their browsers would have led students to articles from Snopes and the BBC debunking the video. Only three students – less than one-tenth of 1% – located the true source of the video, which had, in fact, been shot in Russia.
Credible news outlets reported that a video was staged to falsely show mail-in ballots filled out for Donald Trump being destroyed in Pennsylvania.
Your lying eyes
Why were students so consistently duped? The problem, we’ve found, is that many people, young and old alike, think they can look at something online and tell what it is. You don’t realize how easily your eyes can be deceived – especially by footage that triggers your emotions.
When an incendiary video dodges your prefrontal cortex and lands in your solar plexus, the first impulse is to share your outrage with others. What’s a better course of action? You might assume that it is to ask whether the clip is true or false. But a different question – rather, a set of related questions – is a better starting place.
Do you really know what you’re looking at?
Can you really tell whether the footage is from atrocities committed by Russian forces in the Donbas just because the headline blares it and you’re sympathetic to the Ukrainian cause?
Is the person who posted the footage an established reporter, someone who risks their status and prestige if it turns out to be fake, or some random person?
Is there a link to a longer video – the shorter the clip, the more wary you should be – or does it claim to speak for itself, even though the headline and caption leave little room for how to connect the dots?
These questions require no advanced knowledge of video forensics. They require you only to be honest with yourself. Your inability to answer these questions should be enough to make you realize that, no, you don’t really know what you’re looking at.
Patience is a powerful tool
Social media reports of “late-breaking news” are not likely to be reporting at all, but they are often pushed by rage merchants wrapping an interpretation around a YouTube video accompanied by lightning bolt emojis and strings of exclamation points. Reliable reporters need time to establish what happened. Rage merchants don’t. The con artist and the propagandist feed on the impatient. Your greatest information-literacy superpower is learning to wait.
If there are legs to the video, rest assured you’re not the only one viewing it. There are many people, some of whom have mastered advanced techniques of video analysis, who are likely already analyzing it and trying to get to the bottom of it.
You won’t have to wait long to learn what they’ve found.
This is an updated version of an article originally published on Nov. 16, 2023.
Life in the digital world can be rewarding. It’s convenient to order groceries for pickup, share photographs or music, and keep in touch with family and friends, no matter the distance. However, it can also be draining. The feeling of being constantly “on” and productive has driven people to reconsider their balance in the saturated digital world.
What to do? There is a fuzzy line between healthy and unhealthy digital consumption. Some folks feel the need to fully disconnect from the digital world to understand this boundary. The idea of digital detoxing is gaining popularity. This practice involves intentionally unplugging from digital technologies in the pursuit of balance and digital well-being. Nearly half of Americans report that they are making a conscious effort to regularly step away from their screens.
But is this attempt enough? It’s no surprise that 62% of Americans confess to feeling addicted to their devices and the internet. Despite people’s best efforts to unplug and strike a balance, research indicates that digital detoxes often fall short.
Getting outside, being with someone else and having fun are all good approaches to disconnecting from the digital world. kali9/E+ via Getty Images
Digital well-being is subjective. We research technology andconsumer behavior. Our recent research studied the digital detox journey, where people take a much-needed break from digital consumption, aiming to uncover what supports or sabotages those seeking digital well-being. Our findings highlighted four key strategies to improve the outcome of this journey toward achieving a healthier digital balance: replacement practices, social bonds, mindfulness and digital well-being as a journey.
1. Finding replacement practices
We found that feelings of withdrawal during a digital detox are quite common. For many, reaching for their phones and scrolling has become such a ritual that they often don’t realize they are doing it. Many turn to their devices when bored or stressed, much like an adult pacifier. As a result, finding an alternative to distract your mind and occupy your hands can be crucial during a digital detox.
These replacement practices often involve hobbies or activities that result in play. As adults, people sometimes forget what it feels like to have fun. By separating fun from your task list and engaging in play for its own sake, you can significantly reduce stress levels and boost your digital well-being.
2. Shoring up social bonds
Humans are inherently social creatures. Indeed, tools such as email, text messages and social media offer ways to enhance social connections. This innate desire for connection, however, combined with people’s reliance on technology, can lead to feelings of FOMO – fear of missing out – and anxiety during a digital detox.
The average adult now spends 70% less time with friends than they did two decades ago. Digital devices offer connection, but pieces of the experience are missing, such as the joy of in-person contact and trust in others that can be difficult to get online. So while we’re a more connected society, relationships suffer and people are more lonely than ever.
Therefore, during a digital detox it is vital to fill your cup with community, whether through existing friendships or by creating new ones. We recommend engaging in a digital detox alongside others, because FOMO may rear its ugly head if your friend pulls out their phone during a night out.
Taking a short digital detox with the Offline Club.
3. Emphasizing mindfulness
In today’s fast-paced environment, finding a moment to pause can feel nearly impossible. Many experience solitude deprivation, meaning people often don’t have moments to be alone with their own thoughts. Yet, the ability to just be can allow time for reflection, helping you consider what makes you happy and healthy. Finding moments where you can step away – to be still and silent – can provide a much-needed recharge.
With adults spending about 90% of their time indoors, breaking the routine and heading outside can offer a more holistic perspective on both personal and global well-being. In our study, yoga and meditation were common ways that detoxers found moments to become more aware of their own thoughts, which helped foster more intentional behaviors.
4. Viewing digital well-being as an ongoing journey
Ultimately, digital well-being is a journey. It is not a checklist that, once completed, means you are fulfilled.
Unfortunately, a single detox isn’t enough to cure digital imbalance. Instead, a successful detox often leaves people feeling introspective and curious. Our research participants shared that relapses are common, especially if they don’t set and monitor ongoing goals. Importantly, your needs change and evolve over time. In other words, what works now might not be what you need in the future.
Willpower just isn’t enough. We recommend identifying specific goals for yourself related to your own digital well-being. These aren’t productivity goals but goals to be unproductive. The aim is to unplug in more fulfilling ways. Whether planning a weekly game night with friends or taking a 10-minute walk without your phone, making time to unplug is worth it in the long run.
Researchers still have more to learn to help support digital wellness. We should remember, though, that individual differences play a crucial role in this equation, meaning that the journey to achieving digital harmony is uniquely personal. Thus, as people navigate their tech-saturated lives, it’s clear that finding the right balance is a complex, highly individualized process.
The digital detox journey can be challenging, but many people discover it to be rewarding in the end. People are not machines, however, so recognizing your limits and finding ways to reconnect with yourself and others during a detox can significantly enhance your sense of humanity and digital well-being.
The fastest animal on land is the cheetah, capable of reaching top speeds of 104 kilometres per hour. In the water, the fastest animals are yellowfin tuna and wahoo, which can reach speeds of 75 and 77 km per hour respectively. In the air, the title of the fastest level flight (excluding diving) goes to the white-throated needletail swift, at more than 112 km per hour.
What do all of these speedy creatures have in common? None of them are particularly big, nor particularly small for the group of animals they represent. In fact, they are all intermediately sized.
The reason for this is a bit of a mystery. As animals increase in mass, several biological features change as well. For example, in general leg length steadily increases. But clearly long legs are not the answer, since the largest land animals, like elephants, are not the fastest.
Since the early 2000s scientists have been building OpenSim – a freely available, virtual model of the human body, complete with all its bones, muscles and tendons.
This model has been used in various scientific studies to understand human movement, explore exercise science and to help model the effects of surgery on soft tissues.
In 2019 a group of Belgium researchers took this one step further, and built a physics-based simulation using OpenSim. Rather than telling the model how to move, they asked it to move forward at a certain speed. The model then figured out which combinations of muscles to activate so it could walk, or run, at the prescribed speed.
But what if we took this even further and scaled the model down to the size of a mouse? Or what if we scaled the model up to the size of an elephant? Then we could see which models could run – and how fast.
Predictive muscle-driven simulations of 5kg, 50kg, and 500kg musculoskeletal models moving at 2.25 metres per second.
This is exactly what my team did. We took the standard human model (75kg), and made smaller and smaller models down to 100 grams. We also made the models bigger, up to 2,000kg, and challenged them to run as fast as they could.
Getting the mass just right
Several fascinating things happened when we did this.
First, the 2,000kg model couldn’t move. Nor could the 1,000kg model. In fact, the largest model that could move was 900kg, suggesting an upper limit to the human form. Beyond this size we need to change shape in order to move.
We also found that the fastest model was not the biggest nor smallest. Instead, it was around 47kg, a similar weight to an average cheetah. Crucially, we could look under the hood and see why this was so.
The curve that explains the shape of the maximum running speed with mass is the same shape as the curve, which explains the max ground force with mass. This makes sense: to move faster, you need to push off the ground harder.
So why couldn’t larger models push harder off the ground? It appeared the larger models were limited by their muscles.
A muscle’s ability to produce force depends on the cross sectional area of that muscle. And as animals increase in size, the mass of their muscles gets bigger faster than their cross-sectional area.
This means the muscles of larger animals are relatively weaker. The muscles begin to “max out” above the max speed – and so the model has to slow down.
At the other end of the spectrum, the miniature models have relatively stronger muscles, but have a problem with gravity. They are just too light. They try to push on the ground to produce a large force, but this just causes their body to leave the ground earlier.
To try to produce more force on the ground, they crouch their limbs, just like mice or cats do. This allows them to stay on the ground longer and so produce more force, just like you might when doing a standing jump. But this takes time. And the longer you take to produce force, the slower your stride will be and you still won’t run faster.
So a trade off between ground force and stride frequency begins, and doesn’t end until you reach the intermediate size, where your mass is just right.
The pattern of speed and size for running animals (in blue), showing intermediately size species (like the cheetah) are typically the fastest. Computer-generated models of humans (right), which are then scaled in size from a mouse to a horse (orange dots), show the same pattern, revealing the underlying biomechanical reasons. Christofer Clemente et al.
As fast as we will get
What might all of this say about human evolution?
We know throughout history that the size of modern humans and extinct human species – a collective group known as “hominins” – has varied significantly, from the roughly 30kg Australopithecus afarensis that existed roughly 3.5 million years ago, to the roughly 80kg Homo erectus from nearly 2 million years ago.
So generally body mass has tended to increase – and presumably so too has our running speed. Homo naledi, which existed around 300,000 years ago and weighed around 37kg, and Homo floresiensis, which existed around 50,000 years ago and weighed around 27kg, must have had to sacrifice some speed for their small size.
The average body mass of modern adult humans is around 62kg – a little heavier than the 47kg peak weight that our modelling found, but still close to that ideal size.
Interestingly, many of our fastest long distance runners such as Eliud Kipchoge weigh around 50kg.
So based on our new research, we now know humans today are about as fast as we will get – without large changes to our muscular form.
Oxygen, the molecule that supports intelligent life as we know it, is largely made by plants. Whether underwater or on land, they do this by photosynthesising carbon dioxide. However, a recent study demonstrates that oxygen may be produced without the need for life at depths where light cannot reach.
The authors of a recent publication in Nature Geoscience were collecting samples from deep ocean sediments to determine the rate of oxygen consumption at the seafloor through things like organisms or sediments that can react with oxygen. But in several of their experiments, they actually found oxygen was increasing as opposed to decreasing as they would have expected. This left them questioning how this oxygen was being produced.
They found that this “dark” oxygen production at the seafloor seems to only happen in the presence of mineral concentrates called polymetallic nodules and deposits of metals called metalliferous sediments. The authors think the nodules have the right mixture of metals and are densely packed enough for an electrical current to pass through for electrolysis, creating enough energy to separate the hydrogen (H) and oxygen (O) from water (H₂O).
The authors also suggested that the amount of oxygen created may fluctuate depending on the number and mixture of nodules on the ocean floor.
This research team was trying to understand the implications of mining metals from the deep-sea floor such as lithium, cobalt or copper, funded by an extractions company in an effort to ensure deep sea mining leads to a net benefit to humanity and the Earth system. Lithium and cobalt are used, for example, to make rechargeable batteries for mobile phones, laptops and electric vehicles. Copper is vital for electrical wiring in devices like TVs and radios and for roofing and plumbing.
The investigation was focused on the Clarion-Clipperton zone of the Pacific Ocean, a vast plain between Hawaii and Mexico where millions of tons of these metals have been found. However, scientists believe mining on this scale is potentially unpredictable and can destroy habitats vital to ocean ecosystems. Deep-sea mining can also introduce harmful sediment plumes to fragile ecosystems leading to a growing number of countries calling for a moratorium.
Dark oxygen for life
The implications for this finding may also play a role in life elsewhere.
Oxygen is essential to complex life as we know it. Complex life has evolved and expanded alongside photosynthesisers, which actually produce oxygen as a waste product. Yet this oxygen allows organisms’ metabolisms to be much more efficient than without it.
Without photosynthetic bacteria, the reliance that Earth’s life has on oxygen may well have never happened, in addition to the evolutionary pathway to biodiversity as we know it. But this study shows that rich-nodules on the seafloor may have provided an additional source of oxygen to the biosphere - the zone of life on Earth encompassing all living organisms.
We can’t understand how these nodules may have affected evolution until we understand more about how they formed deeper in time. At the moment, all we really know it that we these nodules would have needed oxygen themselves to form.
Studies like this show how much the origin of life on Earth is still a mystery.
News reports of so-called forever chemicals in drinking water have left people worried about the safety of tap and bottled water. But recent research has shown there are ways to significantly reduce the levels of these harmful chemicals in our water.
Per and polyfluoroalkyl substances (PFAS) are a wide range of synthetic chemicals that are used in many everyday products such as cosmetics, fabrics and food packaging (where they are used to make products resistant to water and grease), as well as in fire-fighting foams.
Unusually in the chemical universe, the structures of PFAS include groups of atoms within the same molecule that imbue them with both water-hating and water-loving properties. They are also resistant to degradation.
While this latter characteristic can improve the quality of the products we buy, it also means it is nearly impossible to break these chemicals down once they escape into the environment. Some PFAS chemicals are are also toxic. For example, perfluorooctanoic acid (PFOA) has been classified as carcinogenic to humans, and has been found to lower immune response to common childhood vaccines.
Concerns about their safety has led numerous jurisdictions to set limits on levels of some PFAS in drinking water. Nevertheless, many news stories have reported on research finding dangerous levels of PFAS chemicals in drinking water sources in England.
With this in mind, my colleagues and I measured concentrations of ten key PFAS in 41 samples of tap water from the West Midlands of the UK and 14 samples from Shenzhen, China. We also measured the same PFAS in 112 samples of bottled water.
We sampled 87 different brands from 15 countries that we bought either from shops or online in the UK and China. The PFAS we tested included many of those regulated in drinking water as well as some others we have found previously in indoor air and dust.
We compared concentrations of PFAS in plastic and glass bottled water, as well as in sparkling versus still water. In neither case did we find significant differences in concentrations of PFAS. In contrast however, in China we found significantly higher concentrations of PFAS in natural mineral water than in bottled purified water.
Crucially, while we found PFAS in every sample analysed, the maximum concentration limits set recently by the US Environmental Protection Agency (USEPA) for some PFAS were only exceeded for PFOA in some samples of tap water from Shenzhen.
Concentrations of PFAS were lower in bottled water than in tap water from the same locality. This finding is in line with studies conducted in other countries like Spain.
It may be reassuring to some extent but our study only examined a relatively small number of tap water samples from two municipalities and cannot be taken as representative of the UK or China overall. There is no room for complacency as the USEPA’s target concentration limits for two of the PFAS we measured are zero.
So, taking note of the lower concentrations we saw in bottled purified water, we examined the effectiveness of boiling and filtration using activated carbon jug filters.
Boiling in a regular kettle reduced concentrations of all ten of the PFAS we tested. The level of reduction varied between different PFAS though. For PFOA and the three other PFAS that we measured for which there are USEPA concentration limits, concentrations reduced by 11%−14% but were much greater (61%-86%) for the more volatile and non-regulated PFAS we examined that are more easily evaporated.
Reductions were greater for all the PFAS we tested (81%−96%) when we passed the water through an activated carbon jug filter. Boiling the water after activated carbon filtration, as sometimes happens in China, reduced concentrations a little further to between 81 and 99.6%.
These results suggest that using a jug water filter can substantially reduce concentrations of some regulated PFAS in our tap water. Boiling water before drinking also reduces PFAS concentrations but is less effective.
Our findings add to those of a 2024 study in Montreal, which suggested that using a filter fitted to the kitchen tap reduced concentrations of 75 PFAS in tap water.
Our findings are a small first step towards reducing our exposure to PFAS. But we should not lose sight of the need to reduce and eliminate such forever chemicals. There’s still a lot we don’t understand about these chemicals but what we’ve learned so far shows that some of them present an urgent threat to the health of both humans and wildlife.
Artificial intelligence-generated summaries of scientific papers make complex information more understandable for the public compared with human-written summaries, according to my recent paper published in PNAS Nexus. AI-generated summaries not only improved public comprehension of science but also enhanced how people perceived scientists.
I used a popular large language model, GPT-4 by OpenAI, to create simple summaries of scientific papers; this kind of text is often called a significance statement. The AI-generated summaries used simpler language – they were easier to read according to a readability index and used more common words, like “job” instead of “occupation” – than summaries written by the researchers who had done the work.
In one experiment, I found that readers of the AI-generated statements had a better understanding of the science, and they provided more detailed, accurate summaries of the content than readers of the human-written statements.
I also investigated what effects the simpler summaries might have on people’s perceptions of the scientists who performed the research. In this experiment, participants rated the scientists whose work was described in the simpler texts as more credible and trustworthy than the scientists whose work was described in the more complex texts.
In both experiments, participants did not know who wrote each summary. The simpler texts were always AI-generated, and the complex texts were always human-generated. When I asked participants who they believed wrote each summary, they ironically thought the more complex ones were written by AI and simpler ones were written by humans.
Have you ever read about a scientific discovery and felt like it was written in a foreign language? If you’re like most Americans, new scientific information is probably hard to understand – especially if you try to tackle a science article in a research journal.
In an era where scientific literacy is crucial for informed decision-making, the abilities to communicate and grasp complex ideas are more important than ever. Trust in science has been declining for years, and one contributing factor may be the challenge of understanding scientific jargon.
This research points to a potential solution: using AI to simplify science communication. By making scientific content more approachable, this work demonstrates that AI-generated summaries may help to restore trust in scientists and, in turn, encourage greater public engagement with scientific issues. The question of trust is particularly important, as people often rely on science in their daily lives, from eating habits to medical choices.
What still isn’t known
As AI continues to evolve, its role in science communication may expand, especially if using generative AI becomes more commonplace or sanctioned by journals. Indeed, the academic publishing field is still establishing norms regarding the use of AI. By simplifying scientific writing, AI could contribute to more engagement with complex issues.
While the benefits of AI-generated science communication are perhaps clear, ethical considerations must also be considered. There is some risk that relying on AI to simplify scientific content may remove nuance, potentially leading to misunderstandings or oversimplifications. There’s always the chance of errors, too, if no one pays close attention.
Additionally, transparency is critical. Readers should be informed when AI is used to generate summaries to avoid potential biases.
Simple science descriptions are preferable to and more beneficial than complex ones, and AI tools can help. But scientists could also achieve the same goals by working harder to minimize jargon and communicate clearly – no AI necessary.
