Sommaire pour January/February 2023 de Discover

Michio Kaku’s Lifelong Quest Even with a smartphone and Google at your fingertips, some things are just hard to wrap your brain around. Take, for example, the seemingly improbable idea that energy does not flow continuously, but is released in discrete packets called quanta. Or the mind-numbing notion that the entirety of the cosmos, spanning some 93 billion light-years across, may be just one in a multitude of parallel universes. That’s where Michio Kaku comes in. The theoretical physicist has built a robust secondary career as a mass-market science popularizer, untangling some of physics’ knottiest concepts and streamlining them for the public. His latest book, The God Equation (Doubleday, 2021), chronicles the long quest to create a “theory of everything” that would combine Einstein’s model of general relativity with quantum…

The tiny girl’s wails echoed down the hallway of the pediatric emergency department. Only 4 years old, Emma was in relentless pain, crying and cradling her tender belly. Her doctors and nurses had tried a variety of pain medications, heating pads and distracting toys, yet nothing seemed to calm her. They didn’t see any obvious cause of her severe distress. Her parents were in tears. Just a few hours before, Emma had been her joyful, happy self, playing in the family’s barn with their cat’s litter of new kittens. She giggled in the hayloft as the kittens jumped around her. Suddenly, her parents heard her scream from the shed nearby. They found her doubled over, clutching her stomach and unable to walk. “What happened?” her father asked, wondering if she…

≫ Last May, scientists reported that they’d successfully grown plants in extraterrestrial soil for the first time. At the University of Florida’s Space Plants Lab in Gainesville, a dozen Arabidopsis thaliana plants germinated and grew, each in a few teaspoons of lunar regolith — the dusty material that covers much of the moon. “The first surprise was that they germinated at all,” says Rob Ferl, who with fellow horticultural scientist Anna-Lisa Paul, directs the lab. “Lunar regolith is sharp and angular. There was no reason to think that plants would embrace it whatsoever.” The second surprise was how they grew, says Paul. Compared to growth in terrestrial soil, these plants were stunted and stressed. Genetic analyses helped explain why. “Even though they looked well, the plants had to engage different kinds of…

≫ THERE IS a time bomb sealed in the planet’s frozen wastes. Scientists in the U.K. have found that by 2060, human-induced climate warming will likely thaw three-quarters of the far-north peatlands found in Scandinavia and western Siberia. If this happens, they warn in a March study published in Nature, an enormous amount of stored carbon, methane and other greenhouse gases could be released. That might fuel a cycle of more warming, more permafrost thawing, and so on. In this scenario, it is unlikely that permafrost in European peatlands would recover during this century. Peatlands are areas where organic matter has died and piled up over eons in an environment so perpetually soggy that decomposition slows to a snail’s pace. Like coal and other fossil fuels, peat contains compressed carbon…

≫ AROUND THE WORLD, people are building levees, shoring up dams, digging canals and constructing infrastructure to confront the impacts of climate change. Most of these investments will likely save countless lives and protect property, but some will inadvertently add to the problems they are trying to address. Experts call this phenomenon maladaptation. It generally refers to a protection effort against the impacts of climate change that backfires and increases vulnerabilities. For years, maladaptation was given short shrift as research and policy prioritized mitigating climate change by reducing greenhouse-gas emissions. Now, with the world lagging utterly behind that effort — in the U.S. alone, reports in 2022 showed that global warming could cost $2 trillion by 2100 — adaptation and its hazards are getting a hard look. This past spring,…

≫ COVID-19 IS NOT the first disease to migrate from animals to humans. The Black Death of the 14th century was spread by fleas that feasted on rats infected with the Yersinia pestis bacterium. The H1N1 virus behind the influenza epidemic of 1918 originated in birds. The list goes on. There was a time when these outbreaks were relatively infrequent, but today, some three-quarters of new infectious diseases emerge from animals. In the last two decades alone, we’ve been hammered by zoonotic outbreaks, including SARS, swine flu, MERS, Ebola, bird flu, and most recently, COVID-19 and monkeypox. (See the story on page 45.) Some researchers have taken to calling this era the Pandemicene, or the age of pandemics. A study published in Nature in April suggests a likely culprit: climate…

≫ IN NOVEMBER 1915, polar explorers watched with gut-wrenching dismay as Antarctica’s Weddell Sea swallowed their ship, Endurance. Ice had trapped and crushed the vessel “beyond all hope,” mission leader Sir Ernest Henry Shackleton wrote. Now marooned on floating ice, the 28-man crew drifted from the continent it had hoped to traverse. With supplies dwindling, the explorers paddled lifeboats to a desolate island and survived on seal and penguin meat. Shackleton and a few mates took one of the small boats, James Caird, and sailed over 800 miles across treacherous seas to bring back help. The crew’s rescue came nine months post-wreck. All survived. Even James Caird made it back to England, where it is still displayed at a school in London. Endurance, however, remained lost — until now. Last February,…

≫ For more than a century, Tyrannosaurus rex has stood as a singular species, a tyrant lizard king without peer. But in March 2022, paleontologists made a controversial proposal: There was more to Tyrannosaurus than just rex, they speculated, suggesting that two additional species had been hiding in plain sight. Tyrannosaurus ruled for quite a long time and left behind significant fossil evidence. Dating approximately 65 million to 69 million years old, more than 50 partial Tyrannosaurus skeletons have been found. And paleontologist Gregory Paul and colleagues say some tyrannosaurs in this fossiliferous collection don’t look quite like rex. According to their Evolutionary Biology paper, paleontologists have uncovered at least three distinct types of Tyrannosaurus, suggesting two new species. Tyrannosaurus imperator, the bulky “tyrant lizard emperor,” was the earliest of…

≫ In recent years, scientists have found plastic pollution in Earth’s most remote places — from the top of Mount Everest to the bottom of the deepest ocean trench. But two studies released in 2022 brought the problem much closer to home. In May, researchers in the Netherlands revealed the presence of tiny particles known as microplastics in the human bloodstream. Using a technique involving gas chromatography-mass spectrometry, which converts materials to gas and measures the mass and charge of their ions, the team examined the blood of 22 donors. In their study, published in the journal Environment International, they found microplastics in samples from roughly three-quarters of the subjects. Concentrations averaged 1.6 micrograms per milliliter, or about a teaspoon of plastic for every 264 gallons of fluid. “We have…

≫ LAST SPRING, the U.K. passed the Animal Welfare (Sentience) Act 2022, marking the first time that animals were declared sentient by British law. The legislation recognized the rights of vertebrate animals such as mammals, birds, reptiles and fish, plus famously intelligent invertebrates like the octopus. While some protections already existed for those creatures, the new act unexpectedly added decapod crustaceans to the mix, including lobsters, crabs and shrimp. The decision to include decapods as sentient animals was founded on the research of biologist Robert Elwood, who has demonstrated over the past decade that these creatures exhibit “responses consistent with the idea of pain.” The professor emeritus at Queen’s University Belfast says it’s impossible to definitively prove how an animal (or person) feels. But in his experiments, prawns rubbed their antennae…

THE VALUE OF HOPE (“Redefining Suicide,” Jul/Aug 2022) As a retired psychiatric nurse practitioner, I read “Redefining Suicide” with great interest. It defined the problem clearly and offered practical information on suicide prevention. However, all of the people quoted in the article failed to mention one thing that I consider of paramount importance in reducing suicide risk: the instillation of hope. Suicide contracts don’t work if no hope is offered. When I was practicing, I had very frank conversations with my patients regarding suicide, specifically impulsivity. When I contracted with my patients, I always tried to offer them hope, reassuring them that I would be with them on their journey and that I was not going to give up trying to help them, and they should not give up either.…

OVER 700 feet (or about 60 stories) above France’s Rhône River stands a cave with more than 40,000 years’ worth of Neanderthal debris. Digging through the materials since the 1990s, archaeologists have found traces of campfires, butchered animal bones and well over 50,000 stone tools crafted in the broad, flat fashion typical of Neanderthals. But after years of excavations, halfway down the 10-foot-deep pits, archaeologists uncovered hundreds of stone artifacts that didn’t belong: finely pointed tools that resembled arrow tips. “Something is not normal in this layer,” says Laure Metz, an archaeologist at Aix-Marseille University in France. “Something happened.” In a February Science Advances paper combining three decades of research, Metz and colleagues concluded that “something” was sapiens: Modern humans inhabited the site, known as Mandrin, and filled it with their…

A HEAVY feeling on the chest. A throat that’s leaden. An unrelenting and overwhelming feeling of isolation. Loneliness hurts — and, over time, it can put the body into a vicious inflammatory state that increases our risk of everything from heart attack and stroke to diabetes and cancer. So, evolutionarily speaking, why do we experience it? Stephanie Cacioppo, a neuroscientist at the University of Chicago Pritzker School of Medicine, says that countless studies have helped researchers formulate a holistic purpose for loneliness. “Our social structures evolved hand in hand with neural, hormonal and genetic mechanisms to support these social structures” — like couples, tribes and communities — “that help us survive and reproduce,” says Cacioppo. While loneliness may be painful to experience today, for our prehistoric ancestors that pain would’ve been…

≫ THE PERSEVERANCE rover has been studying rocks and minerals on Mars since landing there in February 2021. It’s also been listening. A microphone mounted on the rover’s SuperCam instrument can capture snippets of sound and send them back to Earth. Another microphone, mounted on the side, can monitor sounds coming from the rover itself. In April 2022, scientists reported that they’d used those soundbites to calculate the speed of sound on Mars. It was part of the first-ever analysis of the acoustic soundscape on Mars, and it didn’t turn out exactly as predicted. “The main surprise was the fact that there are two speeds of sound on Mars,” says Baptiste Chide, a planetary scientist at Los Alamos National Laboratory in New Mexico. Chide’s job includes listening to the sounds…

≫ The past year saw a flurry of research documenting a phenomenon that fishers and scientists have known for centuries: Fish are surprisingly chatty creatures. “If you think about a lot of fish common names, [like] croakers and grunts,” says Audrey Looby, a doctoral candidate at the University of Florida, “all those types of fish are named after the sounds they make to communicate.” One such creature, dubbed the pigfish, even snorts like a pig, she adds. Yet these fish have long been considered outliers, says Cornell University biologist Aaron Rice. He’s one of the scientists challenging that assumption. In a study published in January 2022, Rice mapped sound-producing species onto a family tree and showed that at least 175 families of ray-finned fishes — the largest and most diverse fish group…

≫ MAGDA MATACHE was “devastated” when she first heard the common name for Lymantia dispar — the gypsy moth. It’s a term that Matache, a Roma activist and the director of the Roma Program at Harvard University’s FXB Center for Health and Human Rights, says carries “a very painful historical weight.” In March 2022, the Entomological Society of America recognized that reality when it announced that L. dispar would now be known as the spongy moth. It joins a growing group of organisms and scientific institutions that have been renamed because their old monikers either contained offensive references to groups of people, or honored individuals who committed human-rights abuses. Still, the choice to rechristen was not made lightly, says Jessica Ware, associate curator at the American Museum of Natural History’s department…

≫ IN MARCH OF 2020, there seemed to be two possible outcomes if you got COVID-19: You succumbed to it, or you ultimately recovered. But months later, some symptoms were lingering far longer than people expected. Frequent joggers who’d caught COVID weeks before started to get winded walking down the block. A U.K. lawmaker stated on Parliamentary record that he was months into long-lasting viral fatigue. Even global sports superstars reported post-COVID malaise. “I came back and it was like a month and a half without even being able to run because my lungs were affected,” soccer World Cup winner Lionel Messi told Argentina’s TYC Sports this May. As the pandemic drags into its third year, the number of people reporting long-COVID aftereffects continues to climb. As of June, almost 1…

≫ IN 2018, a researcher reached into his pocket and pulled out a tooth for Fabrice Demeter. The leader of an excavation in the Annamite Mountains in Laos, Demeter had sent the tooth-bearer and several others in search of fossils. The team returned toting fossil-filled rocks — and the molar. “Immediately I could tell it was a human tooth,” recalls Demeter, an anthropologist at the University of Copenhagen, Denmark. Over the following years, Demeter and colleagues used high-resolution CT scans to compare the tooth’s shape, surface features and internal structure to the same measures from around 400 fossil humans. The molar looked like a bulky tooth from a Neanderthal, but that species has never been found so far from Europe. Identifying another possible match from a more mysterious lineage, the team’s…

≫ ON AN OTHERWISE typical Cretaceous day 66 million years ago, a 7-mile-wide chunk of rock plowed into the Earth’s crust and sparked a dinosaur-destroying mass extinction event. Paleontologists have now ascertained that this world-changing impact occurred during spring in the Northern Hemisphere. The critical evidence comes not from dinosaurs, but from the relatives of today’s sturgeon and paddlefish. Specimens found at the Tanis fossil site in North Dakota, including filter-feeding fish with impact debris stuck in their gills, are thought to have died minutes to hours after the collision. This connection prompted paleontologist Melanie During of Uppsala University in Sweden to take a closer look, inspiring a new approach for pinpointing the moment of impact. “Fish like sturgeons and paddlefishes, although more diverse in the past than they are…

≫ CANCER RESEARCHERS don’t toss around superlatives lightly. In June, however, experts used the term unheard of to describe the results of two different clinical trials. Both studies were reported at the annual meeting of the American Society of Clinical Oncology (ASCO). The first involved rectal cancer, a disease that is seldom fatal if caught in time, but whose treatment often leads to permanent bowel, urinary and sexual dysfunction. At Memorial Sloan Kettering Cancer Center, researchers tried a gentler approach: Instead of chemotherapy, radiation and surgery, they used dostarlimab — a type of drug known as a checkpoint inhibitor, which enhances the immune system’s ability to target and destroy cancer cells. The 18 participants in the trial were chosen because their tumors shared a genetic defect that prevents cells from…

≫ THE WRITING WAS on the wall by May, when a source leaked a U.S. Supreme Court draft opinion striking down Roe v. Wade — the nearly five-decade-old ruling that secured the right to legal abortions around the country. In a 5-4 June decision, the Court made good on its telegraphed intent and overturned Roe. The ruling leaves abortion laws up to each U.S. state. That triggered full bans in at least 10 states this summer, including Louisiana, South Dakota, Kentucky and Texas, with many others passing or pursuing tight abortion restrictions. As the decision came down in late June, women and pregnant people scrambled to figure out how it would affect their lives. Several months later, many clinics are still grappling with a wave of disruption in reproductive health…

≫ THIS YEAR, a historic wave of legislation targeting transgender rights has continued. By November, 17 U.S. states had proposed more than 30 bills that aim to restrict access to puberty blockers and hormone injections for minors. In Alabama, for example, a bill passed this April making it a felony to provide gender-affirming care to transgender minors. If all the other proposed bills are enacted, over 58,000 trans kids and young adults who live in these states would lose access to these medical treatments, according to the Williams Institute at the University of California, Los Angeles. But these measures are facing a growing body of peer-reviewed data on the benefits of gender-affirming care — meaning treatments that help a transgender or nonbinary person match their outward traits with their gender…

≫ FOR MORE than half of 2022, prospects for U.S. action to tame the climate crisis seemed grim. Even as intense heat waves, deadly floods and rampaging wildfires were highlighting yet again the costs of climate inaction, legislative efforts in Congress seemed dead by midsummer. Then, whiplash. In August, President Joe Biden signed the Inflation Reduction Act, or IRA. The name belied its history-making significance: $369 billion committed to slashing greenhouse gas emissions and enhancing energy security. Notably, it’s the first major U.S. environmental law since sweeping amendments to the Clean Air Act in 1990. It’s also the first major U.S. law ever to focus on climate change. Most importantly, analyses by three independent research groups projected the IRA could cut U.S. planet-warming emissions by about 40 percent below 2005…

Excessive drought uncovered these fossilized dinosaur tracks in central Texas this past August. The 113-million-year-old prints were cleaned, surveyed and recorded by volunteers and staff at multiple sites in Dinosaur Valley State Park, where extreme dryness and heat shrank the Paluxy River over the summer. Research shows these tracks were left by an Acrocanthosaurus — a bipedal carnivore that may have been 15 feet tall. The newly revealed prints are part of five known track sites mapped in the park, including a set left by a Sauroposeidon proteles, which stood on four legs at about 60 feet tall. Many of these prints are already back under water. With time, park officials say, sediment will cover and help preserve them long into the future. DISCOVER Magazine (ISSN 0274-7529, USPS No. 555-190)…

RECORD-SHATTERING SEAGRASS Believe it or not, this sliver of an underwater seagrass pasture is all part of the same plant. In fact, scientists have declared it the largest single organism alive today, according to a study published in Proceedings of the Royal Society B in June. (It seized the Guinness World Record from a 4-square-mile mushroom in Oregon, affectionately dubbed the Humongous Fungus.) The seagrass, called Poseidon’s ribbon weed, or Posidonia australis, resides in Western Australia’s Shark Bay and stretches across 77 square miles — over three times larger than Manhattan. The plant germinated from a single seed 4,500 years ago and has been sprouting clonal offshoots ever since.…

ON JUNE 18, 1815, the Duke of Wellington defeated Napoleon Bonaparte’s army at Waterloo (then in the Netherlands, today in Belgium), marking the end of the First French Empire. For 24 grueling hours, the armies clashed in the mud with muskets, lances and swords, leaving 50,000 soldiers dead. The battle was one of the deadliest of the century — and yet, almost no human remains have been found in the battlefield area. But now, for the first time, analysis of historical written accounts and artwork has been used to plot a map that may shed some light on the burials. There are a variety of reasons the Waterloo dead are missing, writes Tony Pollard, director of the Centre for Battlefield Archaeology at the University of Glasgow, in a study published in…

≫ IT STANDS as tall as a house, cost $10 billion to build and required 30 years of work by three international space agencies. Its impossibly smooth, segmented mirror is coated with a thin layer of gold, and its instruments hide behind a sunshield as big as a tennis court. In 2022, following a million-mile journey through space, the largest, most expensive and most powerful space telescope ever created finally opened its eyes to the cosmos. And oh, what a view! NASA released the first deep-field image from the James Webb Space Telescope (JWST) in July. It revealed a dazzling collection of thousands of galaxies and stars, many of which have hidden beyond the telescopic sight of astronomers until now. That’s because JWST sees deeper into space — and further…

≫ For years, NASA’s InSight lander has been shaking up what we know about geologic activity on Mars. After landing north of the equator in 2018, InSight began collecting data on marsquakes using a seismometer it carried to the Red Planet; since then, it has recorded more than 1,300 small quakes. The dome-covered device is not only the first seismometer to be directly placed on the martian surface, but also the first to record tremors on another planet. In May 2022, the lander felt the largest quake ever captured on another world. Estimated to have been magnitude 5 on the terrestrial Richter scale, the marsquake was nearly 10 times more powerful than the previous record-holder. Earth experiences hundreds of such earthquakes each month, but on Mars, they seem to be…

≫ ONE DAY PRIOR, the 3-milewide plume of ash and vapor drifting above the South Pacific had been merely a blip on a weather satellite image. But in the early evening of Jan. 15, 2022, Hunga Tonga-Hunga Ha’apai exploded into the largest volcanic eruption in more than 30 years. The blast blanketed most of the nearby Kingdom of Tonga in centimeters of ash, contaminating and destroying food and fresh water supplies. Waves up to 50 feet high devastated many of the country’s roughly 36 inhabited islands, leaving them bereft of houses, and four people perished. Despite Tonga’s high level of tsunami preparedness, the damage will be long-lasting and costly to repair. Hunga Tonga-Hunga Ha’apai also sent a tsunami racing across the Pacific Ocean and ash hurtling into the stratosphere; the…

≫ THE ANCIENT site of Salvatierra, nestled in the floodplains between the Andes Mountains and Amazon forests, would’ve been a sight to behold. Built a millennium ago, the urban oasis boasted elevated buildings and earthen pyramids, as well as a complex system of canals and reservoirs capable of hydrating thousands of inhabitants and acres of maize during the peak of the South American dry season. Today, the site looks like a mound of forest in the savannah of Bolivia. Decades of excavations have uncovered its ruins. And Salvatierra isn’t alone — archaeologists have identified hundreds of similar mounds, thought to be inhabited between A.D. 500 and 1400 by the Casarabe culture. But only a handful have been seriously investigated due to the cover of dense vegetation. To better understand these sites,…

≫ Scientists have spent decades searching for the underlying cause of multiple sclerosis (MS), a neurological disease that afflicts nearly a million Americans. The highly infectious and exceedingly common Epstein-Barr virus (EBV) has long been a prime suspect, but firm evidence has been lacking — until now. In January, a team led by Alberto Ascherio, an epidemiologist at the Harvard T.H. Chan School of Public Health, released the first study showing strong evidence that EBV plays a key role in most cases of MS. The paper, published in the journal Science, grew out of a 20-year collaboration with the Department of Defense Serum Repository, which stores leftover vials from the blood tests taken by active-duty military personnel as part of regular medical screenings. Testing samples collected from over 10 million…

≫ IF YOU’VE FOUND yourself struggling with persistent melancholy or malaise in recent years, you’re not alone: Twenty-one million adults in the U.S. — or 8 percent of the population — had at least one major depressive episode in 2020. That prevalence is even higher, 17 percent of the population, among 18-to 25-year-olds. With so many people affected, it’s surprising how little we know about depression in the brain and body. The neurotransmitter serotonin has long been a prime suspect for the condition’s cause. That’s largely based on the notion that selective serotonin reuptake inhibitor drugs (SSRIs), which increase serotonin levels in the brain, seem to alleviate depression symptoms for many people. But this July, a team led by researchers at University College London did a systematic review of 17…

≫ THE WORLD’S LARGEST nuclear fusion device, which is currently being built in France by a collaboration of 35 nations including the U.S., is expected to be completed by 2025. Known as ITER (International Thermonuclear Experimental Reactor), the experimental device is poised to demonstrate that fusion energy can be a viable energy source. New advances in fusion technology have dramatically increased its chances of success. With nuclear fission, an atom is split in two, creating enormous energy. Fission powers today’s nuclear power plants (as well as atomic weapons). Fusion takes the opposite approach, fusing two atoms together, rather than ripping them apart. Fusion is different from fission in other ways, as well. Fusion is relatively safe: It produces far less radioactivity and hazardous waste than fission. It doesn’t risk out-of-control chain…

■ A tax credit of up to $7,500 toward the purchase of an electric vehicle, depending on your income and what you buy (with some incentivizing terms and conditions, such as that vehicles must be assembled in North America). If you’re in the market for a used EV, you can claim a tax credit of $4,000 or 30 percent of the vehicle’s value, whichever is lower — if the vehicle is at least 2 years old and you meet certain conditions. ■ Tax credits to help homeowners install clean and efficient energy technologies such as solar panels for electricity. Depending on your circumstances, you may be able to subtract 30 percent of the cost of these investments from your federal taxes. More modest steps for making the home more comfortable…

Crustaceans are not the only creatures that gained legal protections in 2022. In February, Panama passed legislation recognizing the rights of nature itself. The change was spurred by recent fieldwork in the country by marine conservation biologist Callie Veelenturf. The new law recognizes that “natural entities have an intrinsic value … [and] a specific right to exist,” says Constanza Prieto Figelist, the Latin American legal director at the nonprofit Earth Law Center, who helped draft the legislation. Essentially, this means judges must weigh the rights of land developers against the rights (and associated protections) of nature to thrive, and “find a way to harmonize these rights.” Panama now joins dozens of countries with similar laws. Ecuador became the first to include the rights of nature in its constitution in 2008.…