BBC Science Focus MagazineAugust 2017的目錄

To anyone taking a stock check of our planet’s resources, the future doesn’t look bright. Coal, gas and oil supplies are shrinking. Indium, nickel and tantalum – just some of the metals that go into our smartphones – are being used faster than we can dig them up. Food supplies and drinkable water are becoming strained as our planet’s population swells and the climate changes. It’s easy to imagine that the next century could be characterised by scarcity. And that’s without considering the ethical and ecological consequences of acquiring these precious resources. However, there is another way to look at this problem. On p36 Matt Ridley makes his case for a different future, one that’s brighter than you might think. Just one more thing… I’m a big crime fan. Columbo’s…

“All eyes are on the outer Solar System right now. First, astronomers found tantalising clues of a ninth planet beyond the orbit of Neptune. But now there might be a tenth, too. We shouldn’t really be surprised. The early Solar System was a much more chaotic place than the largely serene environment of today. Another planet is thought to have whacked into the Earth to form the Moon, for example. What’s more, computer models of Solar System formation work better if there were more than four gas planets to begin with. Today’s gas planets were the gravitational victors in the Solar System’s childhood squabbles. Planets Nine and Ten, should they be confirmed, were likely bullied into far-flung orbits. But why is it taking until now to find them? After all,…

Steller’s sea cow was a most unusual beast. The herbivorous, cold-water-dwelling relative of dugongs and manatees was discovered in 1741 by Georg Steller when he and his shipmates were marooned on the uninhabited Bering Island in the North Pacific. Rich in blubber and meat, slow-moving and unafraid, this 10-ton, kelp-eating creature proved a tempting target to hunters that winter and in the years that followed. Within three decades of its discovery it was extinct. This is a tempting metaphor for the impact of human beings on the planet. The seven billion people on Earth, together with their domestic animals, use a large proportion of the planet’s resources. They have already caused the extinction of many species. According to Prof Helmut Haberl of Austria’s Klagenfurt University, about 14 per cent of…

When I was small I often entertained the idea that the Moon was alive and observing me. On my way home from school, I enjoyed looking up into the sky, believing that the Moon kept following me to ensure that I arrived safely. This is an example. of animism, which is the belief that inanimate. objects, such as stones, trees and mountains, are all alive. Jean Piaget, the Swiss pioneer of developmental psychology, collected many examples of child animism, such as bringing home more than one flower at the same time so that they would not feel lonely, and moving stones from paths every now and then so that they would not have to constantly look at the same view. As Piaget observed, animism is commonly present in young children…

1 HOW WE DETECT A PINPRICK Using molecular biology and various natural chemicals as ‘probes’, we’ve identified most of the nociceptors in the body that respond to painful events. However, we’re still missing the nociceptor that detects a painful hammer blow, knife cut or pinprick. Several research groups are on the hunt for this elusive nociceptor. 2 WHY PEOPLE DEVELOP CHRONIC PAIN In chronic pain, the A-delta and C fibres often switch on permanently, causing non-stop agony. If we can work out why this happens and manage to prevent it, we’ll have gone a long way to helping millions of sufferers. Also, we still need to understand why, after the same injury, one person can develop chronic pain, but the other person does not. 3 WHERE THE ‘HURT’ IS IN…

“THIS MEANS THE POT OF GOLD AT THE END OF THE RAINBOW IS UNATTAINABLE” Proper summer has finally arrived, along with the opportunity for sitting outside and basking like a lizard through long and lazy afternoons. On a sunny day, while eating al fresco, intense sunlight glints off plates and glasses, and the most important question of the afternoon is whether clotted cream or jam should be spread on scones first. But take a moment away from these ponderings to look at the table – really look – and you’ll see that it’s covered in bright lines and odd dark patches. The surface of your tea is decorated with two sharp semicircles on the side furthest from the Sun. Your transparent glass of water casts a weird dark shadow (even…

YUJIN NAGASAWA Philosophy professor Yujin is the perfect person to investigate panpsychism – the theory that everything, even a rock, is conscious. p64 HELEN SCALES Helen, a marine biologist and scuba diver, loves exploring the oceans. This month, she takes a look the weird creatures lurking off Australia’s shores. p56 IRENE TRACEY Everybody hurts, sometimes. Irene Tracey, a neuroscientist at the University of Oxford, guides us through the science of pain. p70…

“WE MAY BE WITNESSING A REVOLUTION IN THE WAY HUMANITY DEALS WITH THE INEVITABLE UNCERTAINTIES OF LIFE IN A COMPLEX WORLD” Ten years ago this month, an event took place in Paris which signalled the start of EOTWAWKI. No, it’s not a Maori festival; it’s something much less fun: The End Of The World As We Know It. In August 2007, a French investment bank told some of its clients they couldn’t get access to £1bn of their own money. While undoubtedly bad news for those involved, it didn’t seem like a huge story for the rest of us. But what happened on that Thursday afternoon is now widely seen as the start of the Global Financial Crisis. Over the following year, trillions of pounds of wealth evaporated, global financial…

CODING FOR GIRL SCOUTS Girl Scouts in the US can now earn badges for coding, hacking and cybersecurity awareness. The new badges have been introduced in a bid to encourage more young women to pursue careers in the IT sector. CITIZENS OF SPACE Asgardia, a ‘virtual nation’ set up by a Russian scientist last year, already has some 200,000 citizens. And now it’s launching its own small satellite where all those citizens’ data will be stored, along with Asgardia’s flag, constitution and 13-month calendar. TEMPERANCE TAG Police in Lincolnshire are trialling a leg-mounted tag that, instead of tracking the movements of low-level offenders, monitors their alcohol intake. It’s designed to ensure offenders stick to booze-free conditions imposed as part of a community sentence.…

On the flipside In a recent ‘Q&A’ (Summer, p86) you answered a question by Coco Shang that indicates that work was still going on into the reason for toast to usually land butter-side down on being dropped. This is an old chestnut, and surely any school boy will tell you that the usual reason for this occurrence is that the toast was probably buttered on the wrong side in the first place. Peter Duckworth, Ceredigion Re: the ‘Q&A’ question about toast, I recommend ALL scientists to read the excellent book Eurekas And Euphoriasby Walter Gratzer. On page 45, he describes a US scientist investigating this very problem, who found his children’s toast always fell butter-side up. He only discovered later that his children buttered BOTH sides of their toast! Stuart…

 Anti-environmentalists often use a three-part strategy to talk their way around resource limits. First, sow doubt by cherry-picking a few instances where predictions of scarcity didn’t pan out. Second, use the shaky foundation of these failed predictions to dismiss scientific evidence about resource limits. Third, advance the seductive idea that we don’t have to change our behaviour because machines and markets will solve all environmental problems. “WE EXTRACT AND CONSUME RESOURCES AT FAR HIGHER RATES THAN ANY PREVIOUS CIVILISATION” That last point sounds too good to be true, because it is. While we’ll technically never run out of non-renewable resources, there are real impacts from depletion. The harvesting of Earth’s non-renewables follows the low-hanging fruit principle. Extraction industries target resources that are easy to get. As these are exhausted, miners…

We may have learnt to tame it with drugs, but pain is one of the certainties of human existence. It can be both physical and emotional, ranging from a searing torment to a mild soreness. But what exactly is it, what function does it serve, and how can we really know how much pain someone is in? What is pain? Simple, you’d think. You touch a hot saucepan by mistake and it hurts like hell. You immediately withdraw your hand, rush to the tap and run cold water over it. Phew. No need to rush to A&E. But then it throbs for days, reminding you of the burn and your carelessness until the pain fades away. Lesson learned: you’ll be more careful around cookers in future. This simple incident can…

DR ALASTAIR GUNN Astronomer, astrophysicist ALEX FRANKLIN-CHEUNG Environment/ climate expert DR PETER J BENTLEY Computer scientist, author PROF ALICE GREGORY Psychologist, sleep expert PROF MARK LORCH Chemist, science writer CHARLOTTE CORNEY Zoo director, conservationist DR HELEN SCALES Oceans expert, science writer DR CHRISTIAN JARRETT Neuroscientist, science writer EMMA DAVIES Heath expert, science writer LUIS VILLAZON Science/tech writer DR AARATHI PRASAD Biologist, geneticist PROF ROBERT MATTHEWS Physicist, science writer Why do rockets follow a parabola after launch? FRED WILHELM, US Students have long been taught that all projectiles follow a curved path known as a parabola. The explanation is that as they fly, they cover distance both horizontally and vertically – but only the latter is affected by the force of gravity, which bends the path of the projectile into a…

There are two ways that hand creams act to moisturise your skin. Occlusive agents form a barrier that traps water, while humectants attract more water to your skin. The problem is that the humectants are water soluble, while the occlusive agents dissolve in oil. So to get them to mix in an easy-to-use formulation, the creams also need an emulsification system. ML WATER 80 per cent Gives the cream volume and dissolves some ingredients. GLYCERINE 3 per cent Is a typical humectant used to draw water in from the atmosphere. THICKENERS 5 per cent PEG or polyacrylic acid (which may appear as carbomer on the label) are long polymer molecules that increase the viscosity of the cream, making it easier to apply. FATS AND OILS 7 per cent Coconut oil,…

1. Frogs, like all amphibians, have thin, porous skin that they can breathe through. But this also poses a risk because it makes it easier for bacteria to infect them. 2. To protect themselves, frogs secrete substances called cationic antimicrobial peptides (CAMPs). Other animals secrete CAMPs too, but frogs produce much more, including some peptides that are effective against multi-resistant bacteria. 3. Milk goes off because of bacteria, especially species of Lactobacilliand Pseudomonas. These ferment the lactose in milk into lactic acid, and hydrolyse milk proteins into various unpleasant tasting by-products. 4. According to Russian folklore, putting a live frog in milk would help it stay fresh. Recent research has found that CAMPs from the Russian brown frog could kill the bacteria in milk and prevent it from turning.…

TACOMA PC/XBOX ONE ( 2 AUGUST) Tacoma is the latest release from Fullbright, makers of the critically-acclaimed Gone Home. Tacoma is a narrative adventure set in an abandoned space station 200,000 miles from Earth. Its crew of six have been evacuated in mysterious circumstances, and it’s your job to piece together exactly what happened. SONIC MANIA PS4/PC/XBOX ONE/ NINTENDO SWITCH (15 AUGUST) Welcome back, O blue one! Sonic the Hedgehog returns in full 2D, pixellated glory with this homage to the Sega games of yore. There are reimagined levels from the iconic titles of the 1990s, as well as entirely new zones and bosses, plus a welcome return for Tails and Knuckles. UNCHARTED: THE LOST LEGACY PS4 (22 AUGUST) Uncharted 4: A Thief’s End was many critics’ game of 2016.…

The palm cockatoo fancies itself as the next Ringo Starr p16 There is a group of marine animals known as sea spiders p56 Emotions amplify pain, making it feel worse p70 You could throw a frisbee on Mars, but you’d have to put some effort in! p81 Frogs can keep milk fresh p88 CONTACT US Advertising neil.lloyd@immediate.co.uk 01173008276 Lettersforpublication reply@sciencefocus.com Editorialenquiries editorialenquiries@sciencefocus.com 01173147388 Subscriptions bbcfocus@buysubscriptions.com 033301620113* Othercontacts sciencefocus.com/contact WANT MORE ? FOLLOW SCIENCEFOCUS FACEBOOK TWITTER PINTEREST GOOGLE+…

“THE MOST LIKELY EXPLANATION FOR OUR RESULTS IS THAT THERE IS SOME UNSEEN MASS” It seems the Solar System may be a little more crowded than we thought: a planet around the size of Mars could be hidden among its outer fringes. A team from the University of Arizona has discovered a mysterious mass, dubbed Planet Ten, that appears to be tugging at the orbits of a population of space rocks known as the Kuiper Belt in the icy outskirts of the Solar System. The Kuiper Belt lies beyond the orbit of Neptune and extends to a few hundred Astronomical Units (AU) with one AU representing the distance between Earth and the Sun. The Earth and the other major planets all orbit the Sun in roughly the same plane. However,…

“GOING ELECTRIC WOULD DO NOTHING TO REDUCE CONGESTION” Volvo is the first major car company to announce that all its cars will soon have electric motors. None of its new models will rely solely on internal combustion after 2019, and other manufacturers are presumably not far behind. So what does this mean for the environment, and for our congested cities? Are electric cars really as eco-friendly as we’re led to believe? There is one area where electrification clearly brings an advantage, and that is exhaust emissions. Fumes from vehicles are implicated in around 40,000 premature UK deaths every year, with around 9,000 in London alone. Diesel fumes are a major issue here, although petrol is hardly benign. Vehicle emissions cause a host of unpleasant conditions, including cancer, heart disease, diabetes…

What did they do? Computer scientists at Georgia Institute of Technology in the US have taught a robot to compose its own musical pieces, and then play them on the marimba – an instrument similar to a xylophone. How did they do that? The robot – nicknamed ‘Shimon’ – was fed nearly 5,000 complete compositions, ranging from pop songs to classical pieces, and over two million smaller fragments such as riffs, solos and codas. Using deep learning techniques, its AI system then analysed the material and devised its own set of rules for composition. Using these rules, it then ‘wrote’ and played recognisably musical creations of its own. Why did they do that? Project leader Mason Bretan is interested in exploring the possibilities of AI and computer learning in music…

MARS IS COVERED WITH TOXIC COMPOUNDS The surface of the Red Planet is teeming with chemicals that could wipe out living organisms, say researchers from Edinburgh University. This finding greatly reduces the chances of finding life on Mars. OUR BRAINS BENEFIT FROM PHYSICAL EXERCISE Working out can be just as beneficial for our brains as our bodies. A team at the University of Arizona has found that taking exercise leads to improvements in brain structure and function – an effect thought to be linked to our evolution from sedentary apes to active hunter-gatherers. CHILDREN WHO SLEEP LESS COULD AGE FASTER Telomeres are structures at the end of our chromosomes that shorten with age. In nine-year-old children who miss out on sleep, they are significantly shorter than in kids who sleep…

To kick off the ‘Summer of Mars’ events programme at the Kennedy Space Center in Florida, NASA recently unveiled an 8.5m-long concept Martian rover that wouldn’t look out of place in the Batcave. The vehicle consists of a detachable rear section housing a science laboratory, and a front section that’s equipped with radio and GPS. Sadly it isonly a concept: according to the latest information on NASA’s website, the actual rover used in the Mars 2020 mission is likely to be similar in size and appearance to Curiosity, the 3m-long rover that’s been busy exploring the Red Planet’s surface since 2012.…

A South Korean biomedical start-up called Ybrain has developed a headband that they claim will offer relief from the symptoms of depression. The device, called Mindd, works using a technique called transcranial direct-current stimulation (tDCS). Here, a low-voltage electrical current is applied to specific areas in the brain via electrodes placed on the skull. tDCS is not new – the basic principles have been understood since the early 19th Century. But the past decade or so has seen increased interest in its use in treating neurological and psychiatric conditions, and a 2016 meta-analysis of hundreds of studies concluded that it’s “possible or probably effective” as a treatment for depression. tDCS equipment can stimulate particular brain regions either ‘anodally’ (increasing neuronal activity) or ‘cathodally’ (decreasing neuronal activity). The Mindd headset applies…

Brushing up I was fascinated by your article about the work of Prof Richard Muller on the origins of time (May, p38). I like the idea that time is made as a series of ‘nows’, as space-time expands following the Big Bang. With new space, new time has to also come into being. It occurred to me, though, that there might not be any reason for each new ‘now’ to be the same size as the last one. This would have a bearing on the current work on dark energy and the apparent acceleration of the expansion of the Universe. If, as space expanded, the successive ‘nows’ were actually becoming very slightly smaller over aeons, then the expansion of the Universe might not actually be speeding up, but only appear…

CAPSAICIN This chemical, found in chillies, binds to a nociceptor that also responds to extreme heat. This is why biting into a chilli can cause pain. NOCICEPTORS These are receptors on the pain nerve fibres that act like a lock. Certain keys (irritants, mechanical forces, temperature) open them and set off messages to the brain, signalling pain and tissue damage. Over-the-counter painkillers target nociceptive pain. PAIN NERVE FIBRES A , (A-delta) and C fibres are nerves that carry signals from nociceptors in the skin, muscles and joints to the spinal cord. PHANTOM PAIN This is the perception of pain in a limb or organ that’s missing. This most often occurs following the amputation of an arm or a leg. It’s devastating for patients, and some theories suggest that it’s a…

1 NATURE’S ALARM Pain is essential for survival, alerting us that something is wrong and that we’ve possibly damaged ourselves. It prompts us into action and is a great teacher – we learn to avoid things that hurt. 2 ALL IN THE BRAIN Pain emerges from brain activity, but there isn’t a simple one-to-one mapping between the amount of tissue damage and the pain we experience. It’s a highly subjective phenomenon, and our emotions, attention, expectations, and context can all influence the incoming signals to strengthen or weaken the pain. 3 PROBLEM PAIN One in five adults experiences pain that persists beyond three to four months from the original injury – the definition of chronic pain. Our understanding of the biology behind this is vastly improving, so there could be…

1. FOOD CHAIN COLLAPSE Most non-marine food chains depend on insects. Almost all birds eat insects, and even those that eat seeds as adults still feed insects to their young. It takes 200,000 insects to raise a swallow chick to adulthood. Insects also break down plant matter and help recycle nutrients into the soil. Without any insects at all, most bird and amphibian species would be extinct in two months. 2. NO POLLINATION Of the world’s food crops, 75 per cent are pollinated by insects. Without insects, we could still grow many foods, but onions, cabbage, broccoli, chillies, most varieties of tomato, coffee, cocoa and most fruits would be off the menu. So would sunflower and rapeseed oil. Demand for synthetic fibres would also surge because bees are needed to…

Hailed as the biggest breakthrough in genetic science this century, CRISPR is shorthand for a molecular toolkit that allows scientists to make precise changes to the genetic code of living organisms. Strictly speaking, the acronym stands for ‘clustered regularly interspaced short palindromic repeats’, a pattern in the DNA of bacteria first noticed by 1987. For years the role of this pattern was mysterious, but in the mid-2000s clues emerged that suggested it was part of the antivirus defence system of bacteria. Studies showed bacteria took sections of a virus’s DNA and built it into their own genome using an enzyme codenamed Cas. The resulting CRISPR sequences then allowed the bacteria to detect an attack and fight back. But the key breakthrough came in 2012, when teams in the US and…

“Indiana Jones and I have different policies on artefact acquisition. I try to avoid any sort of death trap” What do you do? I dig up dead people and study their teeth and bones so I can work out what their lives were like. An archaeologist, eh? How like Indiana Jones are you? Indiana Jones and I have different policies on artefact acquisition. I go with the systematic, planned scientific excavation and generally try to avoid any sort of death trap. The travel and the worrying choice of clothing are, however, accurate. Hats are critical. I cannot stress how important hats are. Ever found a ‘Lost Ark’? No, but I have found lots of cool stuff. I once found an Aladdin-style, ceramic lamp on a remote Greek island. At the…