Indholdsfortegnelse for New Year 2023 i BBC Science Focus Magazine

PALAEONTOLOGY DISCOVERIES It's often said the ability to make fire is one of the key skills that defines Homo sapiens – it allowed our ancestors to cook food, keep warm and eventually become the most dominant species on the planet. Recently, evidence has been found across Europe to suggest that Neanderthals were also skilled fire users, but now we may have to add another species to the list. Researchers excavating a complex network of caves in South Africa say they have unearthed evidence that Homo naledi, an extinct species of hominid that lived 200,000 to 300,000 years ago, also used fire. The finding was announced at a lecture given at the Carnegie Institution of Science in Washington, DC, on 1 December by Prof Lee Berger of the University of the…

The contents of the last meal eaten by one of the world's first large animals has been discovered by researchers from the Australian National University (ANU). It is the earliest evidence of food eaten by an animal, they say. The team analysed a pair of Ediacara biota fossils, which are ancient forms of life that are the ancestors of all living animals and were the first creatures to develop bodies with features such as heads, tails and guts more than 550 million years ago. To determine what the animals had been eating, they analysed the fossils in search of preserved phytosterol molecules, which are natural compounds found in plants. It turns out they ate green algae and bacteria. One of them, a slug-like creature called Kimberella, ate via a mouth…

An analysis of data collected by NASA's Stratospheric Observatory for Infrared Astronomy (SOFIA) has turned up no evidence of phosphine in Venus's atmosphere. The NASA researchers were following up on the detection of phosphine by Japan's Akatsuki satellite back in 2020. At the time, the discovery got astronomers excited, as phosphine is considered to be a sign of life. This is because phosphine is unlikely to arise from chemical processes on worlds such as Venus, but is known to be produced by microbial life in bogs, swamps and marshes on Earth. “Phosphine is a relatively simple chemical compound – it's just a phosphorus atom with three hydrogens – so you would think that would be fairly easy to produce. But on Venus, it's not obvious how it could be made,”…

ANALYSIS REALITY CHECK As December draws to a close, so too does party season. Whether it's the office Christmas party, a Yuletide family gettogether or New Year's Eve, the idea of socialising fills many people with dread. If all the parties over the festive period stressed you out, the first thing to say is you're not alone. Of course, there's a spectrum of severity, but feeling nervous about socialising is incredibly common. The reason for this is the way we evolved. Throughout our ancestral history, humans needed to work in groups to stay alive. That's why we've developed instincts to care a lot about social stuff, why we're so concerned about things like reputation and status, and why we dread making a fool of ourselves or being left out. But don't…

In the UK, the NHS recommends six to eight glasses, or up to 1.2 litres of fluids, a day, pointing out that we also get water from food. Harvard Medical School recommends four to six cups a day. But it's the more extreme two litres of water a day advice that has won the internet. In 2016, the idea that getting most of your liquids from water is more beneficial was debunked by Dr Stuart Galloway, an associate professor in physiology, exercise and nutrition at the University of Stirling. His study showed a range of drinks, including diuretics like lager and instant coffee, didn't stimulate any additional fluid loss than water when drunk in normal quantities. But nobody can really say how much everyone needs to drink, as we all…

Calories give us an idea of how much energy foods and drinks contain, and have been a dietary obsession in recent decades. Most of us can recite that women need 2,000 calories a day, and men need 2,500. But as NHS guidelines point out, “an ideal daily intake of calories varies depending on age, metabolism and levels of activity, among other things.” Calories are nice theoretical units, says Mellor, but are flawed. While a hazelnut contains a certain amount of energy potential, when eaten it requires quite a lot of energy to break it down – and still more energy will escape digestion. “This is because the energy is inside the fibre, which we can't break down. Whereas the same number of calories from instant noodles are a lot easier…

KEVIN HARDING, BEDFORD It is thought that one of the most common causes of neck ‘cracking’ is gas bubbles in the synovial fluid escaping a tight space. This synovial fluid is a lubricant between the joints, formed by a combination of carbon dioxide, nitrogen and oxygen. If you deliberately roll your neck, it is thought that you can sometimes release these bubbles, resulting in a series of popping sounds that may sound like cracking. The release of the gas build-up explains why muscles or joints often feel looser and more comfortable after they've been ‘popped’ or ‘cracked’.…

HOW TO SPOT A COMET WHEN: THROUGHOUT JANUARY If you find the precision of astronomical predictions impressive, this month's topic might change your mind. C/2022 E3 ZTF is a well-placed comet, possibly about to break the naked eye visibility threshold. However, comets are notoriously difficult to predict, sometimes likened to cats in the way they ignore predictions and do just whatever they please. In astronomy, a bright comet roughly describes any such object visible through binoculars or a small telescope. Many fall well short of this requirement! Comet C/2022 E3 ZTF is a long period comet discovered on 2 March 2022, with an orbit estimated as longer than 50,000 years. Consequently, this is a non-periodic comet; that's what the ‘C/’ in the name means. A periodic comet is typically regarded…

Mood Serotonin and dopamine are two key players involved in regulating our emotions. These are often referred to as ‘happy hormones’ as they promote feelings of pleasure, positivity and, as the nickname suggests, happiness! Sleep Melatonin helps control your body's natural sleep-wake cycle. As night draws in and low light levels are detected by the eyes, melatonin production increases, tellingthe body it's time to go to sleep. Hunger Ghrelin is an appetitestimulating hormone, mainly produced by the stomach. When you haven't eaten in a while and your stomach is empty, ghrelin secretion increases. This sends a signal to your brain to tell youthat you're hungry. Stress Cortisol is released by the adrenal glands in response to stress. It helps the body prepare for ‘fight-or-flight’ by making glucose and other nutrients…

The Royal Institution Christmas Lectures Okay, so we told you about this last month. But we're still super excited to see Prof Dame Sue Black take centre stage at the Royal Institution to share the secrets of forensic science. And if you're too busy thrashing your family at Monopoly to watch, you can always tune in on iPlayer later. BBC Four 26, 27 and 28 December, 8pm Also available on iPlayer Sliced Bread This might be our new favourite radio show. In Sliced Bread, Greg Foot challenges the latest fads and trends in the world of science, health and technology to find out whether the bold claims made by advertisers really stand up. BBC Radio 4 Thursdays, 12:32pm Also available on BBC Sounds The War Of The Worlds It's 125…

2022 IN PICTURES Window on the Universe LONDON, UK 12 JULY This stunning image beamed to Earth by the James Webb Space Telescope (JWST) reveals details of far-flung regions of the Milky Way that we've never seen before. Launched on Christmas Day 2021, from a spaceport in French Guiana, the JWST is the largest telescope ever sent into space. It uses infrared light to show us stars that were previously obscured from view by dust. Its first images, broadcast here to crowds in Piccadilly Circus, London, show the edge of a star-forming region around 7,600 light-years from Earth, in the Carina Nebula, which is home to stars millions of times brighter than our Sun. Hole at the heart of the Galaxy EVENT HORIZON TELESCOPE 12 MAY You would have thought…

The key to beating antibiotic-resistant bacteria could have been hiding in plain sight on our supermarket shelves. Three artificial sweeteners that are commonly used in diet drinks, yoghurts and desserts can dramatically halt the growth of multidrug-resistant bacteria, a study carried out at Brunei University London has found. The sweeteners saccharin, cyclamate and acesulfame-K inhibited the growth of two bacteria, Acinetobacter baumannii and Pseudomonas aeruginosa, which cause pneumonia and sepsis. These bacteria are on the World Health Organization's (WHO) list of ‘priority pathogens’ that urgently need new antibiotic treatments, thanks to the deadly threat they pose to those with compromised immune systems. The team found that acesulfame-K was particularly effective in preventing the bacteria from developing the biofilms that protect them from antibiotics. When used in conjunction with antibiotics, all…

DISCOVERIES ZOOLOGY It turns out that heavy metal singers and bats have more in common than their mutual love of the dark and a tendency to move in groups. They both use distinct structures in their larynxes, or voice boxes, to produce booming, demonic vocalisations, a study carried out at the University of Southern Denmark has found. Echolocating bats are known to have an incredibly wide vocal range. They can make sounds spanning around seven octaves, which is pretty impressive, considering how even Mariah Carey can only manage five. To investigate how they achieve such a feat of vocal gymnastics, the Danish team removed the larynxes from five adult Daubenton's bats, Myotis daubentonii, mounted them in a frame, applied an airflow designed to mimic the animals’ natural vocalisations and filmed…

Actor Chris Hemsworth, who you might know as Thor in the Marvel Cinematic Universe, recently announced that he was taking a break from the limelight after carrying out a genetic test that highlighted he had a heightened risk of developing Alzheimer's disease. To find out whether we all ought to be considering testing ourselves, we spoke to Sir Peter Donnelly, CEO and co-founder of Genomics PLC, and emeritus professor of statistical science at the University of Oxford, about what genetic screening can tell us about our health. WHAT HAPPENS WHEN SOMEONE TAKES A GENETIC TEST? Usually, the test would involve taking a biological sample from the individual. Typically, that's either a blood sample, or a saliva sample. Then the sample would be sent to a laboratory, which would extract the…

DISCOVERIES COMMENT How worried are you about environmental issues? If thinking about climate change and biodiversity loss stresses you out, you're not alone. Psychologists are trying to understand this feeling – referred to as eco-anxiety – and they're finding that this worry may be essential for our fight to save the planet. In late 2021, Australian applied psychologist Teaghan Hogg and colleagues proposed a new scale to help us measure eco-anxiety: the Hogg Eco-Anxiety Scale. It uses 13 questions to capture our complex feelings about the environment. The scale asks about negative emotions like feeling nervous, on edge or afraid about environmental issues, including global warming, ecological degradation, resource depletion, species extinction, the hole in the ozone layer, pollution of the oceans, and deforestation. The scale also measures whether we…

There are some tastes that we're hard-wired to favour. One of those is sweetness. Not only does an early preference for sweetness help to ensure that babies are attracted to the slightly sweet taste of breastmilk, but our general preference for sweetness is understood to be an evolutionary adaptation, motivating us to seek out and consume (once rare) energy- and carbohydrate-rich foods. Sweetness may also have become a signal for safety, as there are hardly any naturally sweet foods that are toxic. The bumps on your tongue, called papillae, also contain thousands of receptors for the other basic tastes: bitter, sour, umami (the rich, savoury taste of cheese, meat and mushrooms), salty, and the recently added oleogustus – which describes the unique taste of fat. Again, these tastes indicate the…

One of the best ways to get the most out of any workout is to make it ‘eccentric’. You might think that running up a hill is better for you than jogging down it, or that climbing a flight of stairs is going to challenge your muscles more than walking down, but in fact, the opposite is true. It seems crazy, but this is the new science of ‘eccentric exercise’. The name comes from the fact that contracting your muscles (to climb stairs or lift weights) is called ‘concentric exercise’, but any work that goes into those muscles while they are stretched and elongated (as you go downstairs or lower the weights) is known as ‘eccentric exercise’ (pronounced ‘ee-centric’). Tony Kay is professor of biomechanics at the University of Northampton.…

RDA – a term from the US that's also familiar in the UK – stands for Recommended Dietary Allowance. In the UK and Europe, the official ideal daily measure for nutrients is called the ‘dietary reference intake’. They're not identical, but both indicate the optimum levels of nutrients needed every day to keep most of the population healthy. Based on averages, these figures can be misleading for individuals, says Dr Susan Fairweather-Tait, professor in health policy and practice at the University of East Anglia Medical School, with a special interest in micronutrients. “Not everybody needs that level of intake,” she says. Nevertheless, she adds, seeing these figures on product and supplement labels is useful as a rough guide. But rather than being taken as instruction for what you need to…

Dinosaurs do live today: as birds. Birds evolved from dinosaurs, and are part of the dinosaur family tree, so technically some dinosaurs did survive the asteroid impact 66 million years ago, by virtue of their fast growth, their biology that allows them to eat seeds, and their ability to fly away from danger. And there are some 14,000 species of them flourishing today. But what about the dinosaurs that perished? Many of them probably could survive today. Dinosaurs ruled the world for 150 million years, and endured hot and cold spells, volcanic eruptions, and changing sea levels. There is nothing about today's world that would be fatal to them. With that said, the major difference between the world of dinosaurs and today is that our modern Earth is considerably colder,…

Seasonal affective disorder (SAD) is a type of depression that comes and goes in a seasonal pattern. The exact cause isn't fully understood, but it's often linked to reduced exposure to sunlight during shorter days. Some people find that a light box, called an SAD lamp, can help. These produce a very bright light to simulate sunlight. This is thought to encourage your brain to reduce melatonin (the hormone that makes us sleepy). Light therapy has been associated with a reduction in fatigue on a short-term basis. However in 2019, Cochrane (the global independent research network whose reviews are considered the gold standard for research) published a systematic review of light therapy for SAD, and concluded that the quality of evidence about whether light therapy prevents winter depression is very…

Q&A ADRIAN FLINT, VIA EMAIL When David Beckham curled a free kick into the goal against Greece to take England into the quarter-finals in the 2001 World Cup, he was exploiting the Magnus effect. A ball that is kicked head-on travels with the air flowing past it symmetrically in all directions. Friction with the surface of the ball causes the airflow to initially follow the contour of the ball before forming a turbulent wake that trails behind. The interactions of this wake with the surrounding air are extremely complex but they form a significant part of the overall aerodynamic drag on the ball. This interaction changes when the ball is initially kicked off-centre, sending it spinning on its own axis as it travels. The air flowing past the side of…

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MEDICINE Heart disease is one of the biggest killers in the UK. According to the British Heart Foundation, cardiovascular diseases are currently responsible for around a quarter of all UK deaths, which is around 160,000 deaths per year. Patients deemed to be most at risk are prescribed statins, which are drugs that lower the level of cholesterol in the blood and protect the insides of the artery walls. But signs of the disease are not always picked up early, meaning that many patients who would benefit from taking the drugs are not receiving them. Now, researchers based at Massachusetts General Hospital have developed a deep learning AI model that can reliably predict a patient's 10-year risk of death from a heart attack or stroke by analysing a single chest X-ray.…

HEALTH The cause of irritable bowel syndrome (IBS) has remained a mystery ever since it was first described more than a century ago. Now, Prof Brennan Spiegel at Cedars-Sinai Medical Center in Los Angeles, has published a theory in the American Journal Of Gastroenterology that suggests it could be caused by the body's inability to cope with gravity. IBS affects around 10 per cent of the population. Sufferers experience painful cramps, bloating, diarrhoea and constipation, which can last for weeks or months at a time. There is currently no cure, but certain medications or dietary changes can help ease the symptoms. There are several more traditional theories for the cause of the disorder, including abnormalities in the gut microbiome, miscommunication between the gut and the brain, or issues with the…

DISCOVERIES COMMENT A proton should be one of the simplest objects in physics. It's a basic building block of all atoms, or, alternatively, the simplest possible atom all by itself, since hydrogen (one positively charged proton plus one negatively charged electron) is still hydrogen when it's ionised. Most of the atoms in the Universe are hydrogen, as are most of the atoms in your body. In fact, since electrons are tiny and weigh very little, it's straightforward to conclude that you are mostly, specifically, protons. Given all this, you'd think physicists would understand protons very well by now. You would be wrong. If you ask your physics teacher what protons are made of, they'll likely tell you protons are made of three smaller particles called quarks. Quarks come in six…

The carnivore diet Social anxiety Food aversions “Side effects are similar to those reported for the ketogenic diet: bad breath, constipation, diarrhoea, headaches, dehydration” Visit the BBC's Reality Check website at bit.ly/reality_check_ or follow them on Twitter @BBCRealityCheck You've probably heard of the ketogenic diet and you may have heard of the paleo diet, but have you heard of the carnivore diet? This emerging diet trend takes lowcarbohydrate diets to a new extreme. The carnivore diet excludes all plant foods; only foods derived from animals are consumed, including meat, fish, animal fats (lard and ghee, for example) and low-lactose dairy products. So, breakfast might be eggs and bacon with cream, lunch could be cheese-topped meatballs (no herbs added) with chicken breast and, finally, roast beef and salmon for dinner. Advocates of the…

Everything points to the idea that Google should be a dominating force in the world of wearables. Google owns the massive wearable brand Fitbit; it's the maker of Wear OS, the software that most Android smartwatches run on; and it's Google, one of the biggest names in technology! So it's surprising that Google hasn't made a smartwatch… until now. The Google Pixel Watch is the brand's first smartwatch. But with a hefty £339 price tag and some tough competition, is this the future of wearable tech or yet another device we'll forget about in a few years? I spent some time with it to find out. DRESS TO IMPRESS The watch looks great. It's one of the best-looking smartwatches out there, dare I say. It's sleek, stylish and – compared…

…start a radio show from anywhere In a world where everyone thinks they should host a podcast, the Blast Mic is a dangerous but brilliant tool. A small device slapped with an aggressively neon display, the Blast Mic lets you record audio and upload it live to the Blast Radio app (for podcasts and audio shows). This cuts out all of the fiddly steps in the middle, allowing anyone to easily start a radio show without needing loads of equipment and time. It's the perfect gift for that family member who has a lot to say this Christmas, giving them a speaking platform that isn't the dinner table. Blast Mic $249 (£205 approx), blastradio.com …a watch for every sport ever Garmin's new Instinct Crossover Solar is for people who exercise…

On top of a nearby rock, a marmot perches, rotund from a summer of feasting. Cowbells chime in the green pasture below. The path ahead is blocked by a stubborn herd of sheep. As I approach, they scurry up the rocky cliff. Balancing stone to stone, I cross a small stream, before zigzagging up the mountainside. The higher I go, the harder it is to breathe, the altitude and heavy backpack weighing me down. I'm now past the tree line. The ground is barren, except for some lichen clinging to the rocky ground. A vulture circles above. Its vast wings outstretched, swooping in for a closer look, before soaring upwards on a thermal and disappearing from view into a cloud. Another looms out of the white-grey sky, then another. Soon…

Five-a-day started out as a health marketing slogan in the US. “[It was] loosely linked to populations that had more fruit and vegetables having lower risk of heart disease or longer lives,” says Dr Duane Mellor, a British Dietetic Association spokesperson and registered dietitian. “The World Health Organization data now shows eating half a kilo of fruit and vegetables daily is a minimum to see lower instances of disease.” Five good handfuls should provide this quota, but the more the merrier. Five-a-day may be super catchy, but in practice it can be problematic. Fruit juice counts as a daily portion in the UK, even though you're getting the concentrated sugar hit of many more fruits than you'd eat, without the fibre, potentially causing a sugar rush and tooth decay. In…

According to UK guidelines, adults should stick to no more than 14 units of alcohol a week, spread over a period of three days or more. “If you stick to a maximum of 14 units a week, your chances of dying of an alcohol-related disease are probably one in 100 or less,” says Sir Ian Gilmore, chair of Alcohol Health Alliance UK and founder of Liverpool Centre for Alcohol Research. “It's estimated most people would accept a risk of one in 100, as nothing in life is free of risk.” The struggle, however, is getting people to adopt those recommendations. The drivers of how much people drink, and how much harm is seen, are basically price, availability and marketing, he explains. Plus, as he says, most people enjoy a drink.…

Website cookies are little files of information that a webpage tells your computer to store, and then access later. They're named after fortune cookies, an object with an embedded message. They tend to be the same size: 4,096 bytes. Not so big, but when each website could be saving 50 or more of them, they can be used to store a lot about you. There are three types of web cookies: session cookies, persistent cookies, and third-party cookies. When you click into ‘manage cookie preferences’, the first two types may be listed under ‘necessary’ or ‘preferences’, while third-party cookies may be listed under ‘tailored advertising’, ‘marketing’ or ‘analytics’. Session cookies only last while you have that webpage open. They are often helpful – they enable an online shop to remember…