Sommaire pour 8 July 2023 de New Scientist

A STUDY of more than 22,000 people with multiple sclerosis (MS) has identified a genetic variant associated with the condition’s severity. It was seen in people who experienced quicker progression of the disease, and the finding could lead to better treatment. MS is a neurodegenerative condition that causes brain lesions and leads to difficulties with walking, memory and other bodily functions. Some people with it can lead relatively normal lives with treatment, while others experience rapid disease progression. To investigate this disparity, Adil Harroud at McGill University in Canada and his colleagues performed a genome-wide association study using data from more than 22,000 people with MS. Such studies use statistical analysis to pinpoint genes associated with certain characteristics. After analysing almost 8 million genetic variants, the researchers found one that…

GREAT apes in South-East Asia have been heard making calls that are akin to beatboxing. They can produce vowel and consonant sounds at the same time – a complex feat even for us – shining light on the evolution of human speech. Adriano Lameira at the University of Warwick in the UK and his colleagues recorded two groups of orangutans in two distinct locations in Indonesia for about 3800 hours. The researchers found that female orangutans in Sumatra simultaneously make consonant-like kissing sounds and vowel-like hu-hooing sounds to warn their group if predators are around. Similarly, males in Borneo have a call that uses both mouth chomping and guttural grumbles that come from the larynx at the same time (PNAS Nexus, doi.org/kg3j). The sounds are striking and complex, says Lameira, comparing…

ONE miserable morning in 2017, in the third year of my job as a mathematics professor, I woke up to a worrying email. A colleague had questioned the proof of a key theorem in a paper I had co-authored. The proof, he noted, appeared to rest on a tacit assumption that wasn’t warranted. Much to my alarm, I realised immediately that he was correct. After an anxious week working to get to the bottom of my mistake, it turned out I was very lucky. The theorem was true; it just needed a new proof, which my co-authors and I supplied in a follow-up paper. But if the theorem had been false, the whole edifice of consequences “proven” using it would have come crashing down. The essence of mathematics is the…

Book The Age of Guilt Mark Edmundson Yale University Press IN HIS Freudian analysis of what we might loosely term “cancel culture”, Mark Edmundson wisely chooses not to get into simplistic debates about which of the psychoanalyst Sigmund Freud’s ideas have or haven’t been “proved right”. What would that even mean? Psychology isn’t so much science as it is engineering – applying ideas and evidence to a purpose. In The Age of Guilt: The super-ego in the online world, Edmundson, a literary scholar, simply wants to suggest that Freud might help us better understand our cultural moment. In the centre of Freud’s model of the personality sits the ego, the conscious bit that thinks – and therefore is. Bracketing the ego are two components of the personality that are inaccessible…

Editor’s pick The moment is upon us to change tack on the climate 24 June, p 8 From Michael Graham, Peterborough, Cambridgeshire, UK As Madeleine Cuff reports, 2023 is shaping up to be the hottest year on record: global warming is being exacerbated by El Niño conditions and the temperature of the oceans is particularly alarming. The case for intervention is only growing. Steuart Campbell’s letter (24 June) cites Stephen Salter’s idea of marine cloud brightening. This is a safe form of geoengineering using seawater sprayed from ships to brighten clouds. It could be turned off instantly and the effects would be gone in a few days. You can judge Salter’s presentation to the UK’s Royal Meteorological Society for yourself, as it is available online under the title “Marine cloud…

Dear reader, The PPA awards are the UK’s most prestigious magazine prizes and competition is stiff. I was therefore really delighted that my colleague Graham Lawton won Writer of the Year at the awards last week. As regular readers will know, Graham is a world-class journalist and he brings huge heft to what we do at this magazine week in, week out. Many congratulations, Graham. But that wasn’t the only good news last Wednesday night. New Scientist also won Consumer Media Event of the Year for our flagship live show in London. New Scientist Live, led by my brilliant colleague Adrian Newton, is a huge team effort. Many congratulations to Adrian and everyone else involved. This year, the event kicks off at ExCeL London on Saturday 7 October. There will…

PATTERNS of brain activity may show when a person is working to overcome negative emotions. This could help to identify people who have trouble doing this. A reduced ability to control emotional responses, known as emotional dysregulation, has been linked with conditions such as anxiety and depression. To investigate what happens when people try to modify their emotional response, Jared Rieck at the University of Colorado, Denver, and his colleagues scanned the brains of 82 people as they looked at 15 neutral images, such as a photo of an umbrella, and 30 emotionally negative images, such as a photo of someone ill in hospital. They then asked the participants to try to think less negatively about half of the emotionally negative images while they looked at them, for example by…

NEARLY one-third of all known vertebrate species across the world are used or traded by humans. “We’ve become this kind of super-predator,” says Rob Cooke at the UK Centre for Ecology & Hydrology. Cooke and his colleagues have analysed data from the International Union for Conservation of Nature on 46,755 species of vertebrates, which includes all known mammals, birds, amphibians, reptiles and fish. The records show how people use each species. This includes killing them for food, clothing, specimen collections and recreational hunting, as well as taking them from the wild to be pets or to display in zoos. The team found that 14,663 species, around a third of the total, are used or traded. About 55 per cent of these are killed for food and 40 per cent are kept…

MALE frogs often force females to mate with them, but in one species, a croak from the female seems to persuade males to leave her alone. “In general, male frogs are known to jump on even inorganic objects if they are female-like,” says Makoto M. Itoh at Nagoya University in Japan. “However, this species [stops attempting] such holding behaviour at the sound of a female’s call. I consider it rather gentlemanly.” Most frog calls are produced by males as they try to attract mates. A few years ago, Itoh discovered that female black-spotted frogs (Pelophylax nigromaculatus) call quietly as well. To investigate the purpose of the female calls, Itoh captured 15 males and 27 females from ponds in Kyoto during the frogs’ annual breeding season. Fourteen of the females had…

MYSTERIOUS neurons in the clitoris and penis turn out to respond to vibration and light touch, and seem crucial for healthy sexual function. The finding may explain why vibrators are sexually stimulating. Lijun Qi at Harvard University and his colleagues used staining techniques to examine clusters of nerve endings from the clitorises and penises of mice, known as Krause corpuscles. They were discovered in humans in 1860, but their function was unclear. The team found the corpuscles were densely concentrated in the clitoris and more sparsely spread in the penis of mice. Next, they applied stimuli to male and female mouse genitals. The neurons inside the Krause corpuscles were most responsive when the genitals were touched with a vibrating device or stroked with a paintbrush, as determined by measuring their electrical activity.…

WHEN it comes to relieving short-term lower back and neck pain, opioids are no more effective than placebos. This type of discomfort affects up to 500 million people globally and doctors commonly prescribe opioids as painkillers for it. Yet opioids can be addictive, which may lead to drug abuse. Andrew McLachlan at the University of Sydney and his colleagues have studied 347 people with acute lower back or neck pain, in which half took the opioid oxycodone daily and half took a placebo. They also gave everyone typical pain management advice, such as keeping active. After six weeks, both groups rated their pain as having reduced the same amount, suggesting that the opioid and placebo were as effective as each other (The Lancet, doi.org/kg3m).…

Non-native bees worse for plants Honeybees are no friends to some of the plants they visit. Native plants pollinated by non-native, wild honeybees produce seedlings that are far less likely to survive and reproduce than those from plants pollinated by native pollinating insects (Proceedings of the Royal Society B, doi.org/gsdxvb). Climate change is turning snow to rain A shift from snow to rain due to climate change is making extreme rain and flooding more severe in many regions dominated by snow. In the Himalayas, Alps and Sierra Nevada, the intensity of extreme rainfall has increased by an average of 15 per cent for each degree of warming (Nature, doi.org/kg5k). Low iron levels in US young women Nearly 40 per cent of girls and young women, aged 12 to 21, in…

Grace Wade Reporter New York In honour of Pride Month, I went to see Love + Science by cell biologist David Glass, performed at New York City Center. The play follows the lives of two gay medical students (pictured) during the AIDS crisis in 1980s New York and offers a stark reminder of how furiously the queer community had to fight for AIDS to be taken seriously. It also reflects some of the emotions we all remember from the early days of the covid-19 pandemic, such as the fear of inadvertently spreading the disease and the anxiety of waiting for a vaccine. I am currently reading The Price of Peace: Money, democracy and the life of John Maynard Keynes, a biography of the famous economist by Zachary D. Carter. It…

IMAGINE you could see through everyday objects to the stuff they are made of. If you zoomed in on the arm of a chair, say, you would see that it is made of atoms. Zoom in again and you would see that those atoms contain subatomic particles called protons, neutrons and electrons. Zooming further still, you would see that the protons and neutrons are composed of quarks. These are the layers of reality, and this is how physicists understand the universe: by breaking everything down into its constituent parts, an approach known as reductionism. As a particle physicist, I grew up on this philosophy. It has brought physics a long way – it is how we built our current picture of matter and its workings, after all. But now, with…

THE bouts of terrible pain began further back than Victoria Gray can remember. Her grandmother would try to ease the discomfort with hot towels and medication, but it was fruitless. “I was born having to endure pain,” she says. “It was a life that I felt wasn’t worth living.” Gray has an inherited condition known as sickle cell disease, which causes red blood cells to form an abnormal “sickle” shape that can block capillaries, causing pain and sometimes organ damage. As Gray aged, her pain got worse. On one occasion, she temporarily lost the use of her arms and legs. By her 30s, Gray required in-home care. So, when she was offered the chance to become the first person to receive an experimental CRISPR gene-editing treatment, she took it. Today,…

ON 14 April this year, the European Space Agency sent a new spacecraft off on its eight-year journey to Jupiter. The Jupiter Icy Moons Explorer (JUICE, illustrated right) will fly by three of Jupiter’s four biggest moons, Europa, Ganymede and Callisto, before going into orbit around Ganymede, the biggest moon in the solar system. This is an exciting mission because these icy moons, with their subsurface oceans, are some of the most promising places to look for life. And now that Jupiter is once again appearing in our night skies, we can see those icy moons ourselves. The four biggest moons of Jupiter – Io, Europa, Ganymede and Callisto – are collectively known as the Galilean moons, because Galileo Galilei observed them in 1610, making them the first moons discovered…

LITTLE more than a decade ago, a new technology was revealed to the world: CRISPR, a way to change DNA inside cells in a more precise way than ever before. The news triggered a storm of media coverage and earned its developers a Nobel prize in 2020. This year, the first genetic therapy based on CRISPR is set to be approved. This is for sickle cell disease, a condition in which a faulty protein causes red blood cells to form an abnormal “sickle” shape, which can lead to blocked blood vessels, agonising pain and even organ damage. The CRISPR approach activates a gene that can make the correctly-shaped blood cells. This one-off treatment can relieve a lifetime of hardship. Yet there is a catch. Although a price for the therapy,…

THERE are five species of Atlantic cod, researchers have claimed after conducting a genetic analysis of the fish. “What we thought was a single species is actually more species,” says Einar Árnason at the University of Iceland. “It’s important in terms of biodiversity.” Not everyone agrees with the findings, though. Árnason and his colleagues have sequenced the genomes of nearly 1700 Atlantic cod, currently regarded as a single species called Gadus morhua, from across the Atlantic Ocean. For comparison, they also sequenced the genomes of several related species, including Pacific cod and Greenland cod. They found the Atlantic cod genomes could all be put into one of five distinct groups. “They are not interbreeding,” says Árnason. There is a lot of overlap in the geographic areas where the five cod groups…

AS WE age, our muscle fibres become misshapen, but resistance training seems to at least partially restore them. Casper Søendenbroe at Copenhagen University Hospital in Denmark and his colleagues have looked at samples taken from the thigh muscles of about 200 people aged between 20 and 97. The researchers gave the muscle fibres a score based on how much their cross-sectional shape deviated from a circle. Healthy muscle fibres deviate slightly because they have a pentagonal or hexagonal shape, scoring about 1.2. Misshapen fibres may have an elongated or “squashed” shape, with extremely askew ones scoring around 1.9. For each sample, the scores of fibres were averaged to get an overall figure. In the slow-twitch muscle fibres used for endurance activities, there was a small, gradual increase in misshapenness with…

AFTER more than a decade of searching, the IceCube neutrino detector in Antarctica has found high-energy particles from within our galaxy, the Milky Way. The disc of the Milky Way is bright in every wavelength of light – particularly in gamma rays, which tend to be accompanied by neutrinos. But any neutrinos from within our galaxy have historically been overwhelmed by stronger signals from other galaxies, so we haven’t been able to observe them. “It took us 10 years to find the galactic plane in neutrinos,” says IceCube head Francis Halzen at the University of Wisconsin-Madison. “It’s totally counterintuitive. It’s like if you went outside at night and saw a sky bright in active, distant galaxies, but no Milky Way.” The IceCube collaboration applied a machine-learning algorithm to the data…

SHORTLY after hatching, young squash bugs go on a mission to find and eat adults’ faeces so they can acquire bacteria they need to survive. They are forced to do this because they don’t inherit the vital bacteria from their parents. Squash bugs (Anasa tristis) are agricultural pests that commonly attack courgette, also known as zucchini, and pumpkin crops in North and Central America. The bugs have a symbiotic relationship with Caballeronia bacteria, which live in their guts and are crucial for their growth, development and survival. Other species that require symbiotic bacteria, like stink bugs, get immediate access at birth because their mothers leave bacteria-rich faeces on their eggs. However, squash bugs aren’t left the same inheritance, says Scott Villa at Davidson College in North Carolina. “They basically leave…

A ROBOT can change its wheels into propellers and hands, giving it a huge range of movements. Morteza Gharib at the California Institute of Technology and his colleagues drew inspiration from the animal kingdom to create the Multi-Modal Mobility Morphobot, or M4 for short. It has four appendages that can turn into wheels, thrusters, legs and hands. By shifting between different modes, it can fly, roll, crawl, crouch, balance, tumble, scout and pick up objects. In scouting mode, inspired by the way meerkats stand on their hind legs, the robot becomes upright to get a better view of its surroundings (Nature Communications, doi.org/gsdssv). Such mobile robots could be useful for exploring other planets, delivering packages in hard-to-reach locations or aiding search-and-rescue operations.…

Book The Good Virus Tom Ireland Hodder & Stoughton EVERY so often I remember that I should be scared, not just of climate change and creeping authoritarianism, but also of antibiotic resistance. As bacteria acquire the ability to fend off ever more antibiotics, we risk returning to a time when a simple bacterial infection could mean death. To tackle the threat, some researchers are developing new antibiotics to replace the old ones that no longer work. It is expensive and time-consuming. What if there was a simpler solution? What if we could use viruses to cure bacterial infections? That is the premise of science journalist Tom Ireland’s debut book, The Good Virus: The untold story of phages: The most abundant life forms on Earth and what they can do for…

THERE is a line in Best Interests that haunts me. In the first episode of this four-part BBC drama, a doctor (Kevin Eldon) tells Nicci and Andrew Lloyd that their baby daughter is unlikely to lead a long life. “Please don’t assume that Marnie’s story is going to be any less beautiful,” he says. “It’ll just be different, and you have to adapt to that difference. And you’ll find such joy if you do.” Marnie (Niamh Moriarty) has a severe form of muscular dystrophy, a degenerative condition with no cure. She has grown into a funny, sweet-tempered 13-year-old. When Marnie is in good health, Nicci and Andrew (Sharon Horgan and Michael Sheen) are two big kids who seem settled in their love. Returning from a rare holiday away from Marnie…

With one CRISPR therapy set for approval and more to follow (see main story), a new question arises: should we edit the genomes of embryos, eggs or sperm so that the DNA in all of the cells of our children is changed, and those changes are passed down the generations? For now, there is no compelling reason to do so. Almost every inherited genetic condition can already be prevented by existing forms of screening, including by testing IVF embryos before implantation. By contrast, using CRISPR is risky because it isn’t guaranteed to fix the disease-causing mutation in all cells in children’s bodies, and could introduce unwanted or dangerous mutations. As a result, there is near-unanimous agreement among experts that no one should be attempting heritable genome editing at present. And…

Flowery language Polymorphic perversion has fallen by the wayside in academia. As a subject of study, that is. Research publications in recent years make few overt mentions of it. The phrase and long-running quarrels as to its meaning are associated with psychoanalyst Sigmund Freud, whose death in 1939 prevented him putting paid to those quarrels. Grażyna Gajewska at Adam Mickiewicz University in Poland is one of the few academics who is now overtly studying polymorphic perversion on a broad, societal level. Her recent treatise “Polymorphic perversion of human and other-than-human bodies” appears in the journal Porównania. Gajewska gives a peek into aspects of life that will be new to many readers. She focuses mainly on our relationships to plants, rather than to bacteria, archaea or non-human animals. Her paper, she…