Snworld

Why do we go red in the face when embarrassed? Humans seem to be the only animals to show embarrassment, and Charles darwin called blushing “the most peculiar and most human of all expressions”. A 2009 study by dutch psychologists found that we are more likely to give people a second chance if they blush when they betray us. the ability to blush acts as a signal that you are sensitive to the social rule you have just broken. Psychopaths, on the other hand, do not blush at all.

Could direct air capture prevent climate change ? direct air capture (dAC) is an appealing way to tackle climate change: just pass ambient air over chemicals that absorb the Co2 driving global warming, and then use or store the Co2. dAC differs from the better-known carbon capture and storage (CCs) in that it can be done anywhere, not just at big sources of Co2 such as power stations. it’s more effective than natural Co2 ‘scrubbing’ using trees and plants, and can be performed where the Co2 is most easily stored or re-used. unlike CCs at power stations, dAC must be effective at removing the far more dilute Co2 in ambient air. this demands special equipment and chemicals, plus renewable energy sources producing zero Co2. that has led to grave doubts about the economic viability of dAC. For now, it remains an intriguing but impractical remedy for global warming. 

How do we know when something is wet?  our skin contains lots of nerve endings that respond to different stimuli. there are receptors for touch, vibration, heat, cold and pain – but not for wetness. water is such a ubiquitous component of all living cells that it would be difficult for a nerve cell to avoid firing constantly in response to its own composition. instead, wetness seems to be a property that our nervous system learns to recognise, based on a mixture of cold, pressure and texture. A 2014 study at Loughborough university found that hairy skin is more sensitive to wetness than smooth skin, which may be because hairy skin has more temperature sensitive nerve endings. when you are born, you don’t feel wet or dry, you just feel cold or warm. over time we learn that the feeling of cold cloth sticking to our skin means that we’ve sat on a wet park bench.

Why do snakes have slits for pupils? Vertical pupils are an adaptation for ambush hunting. A 2010 study at sydney university found that of 127 Australian snake species, the ones that ambushed their prey by night had vertical pupils, while those that actively chased down prey in the day had round pupils. the constriction of round pupils helps distant prey stay in focus, but it also lets in less light. Vertical pupils improve vision across a wider range of light levels, and enable the animal to detect horizontal movement more effectively. it’s also possible that vertical pupils are more camouflaged, since they break up the round outline of the eye

Why does it feel good to scratch? studies using funCtionAL magnetic resonance imaging (fMri) have shown that scratching causes patterns of brain activity that are associated with pleasure and reward. this effect is strongest when you do the scratching yourself and when you are actually scratching an itch, rather than just an arbitrary patch of skin. But contrary to what you might expect, or might have read elsewhere, there’s no clear evidence that this pleasure comes from a release of endorphins – it happens purely in your brain and spine. this mechanism may have evolved to encourage us to dislodge skin parasites. All the evidence suggests that it’s a very ancient response, because all vertebrates scratch themselves – even fish! 

Can germs survive on a bar of soap? Yes. when you wash your hands, you  transfer a thin film of bacteria, skin flakes and oils to the bar of soap. A 2006 study of 32 dental clinics found bacteria growing on the soap in all of them – after all, standard soap doesn’t kill bacteria, it just dislodges them. A 1988 study found that washing your hands with a dirty bar of soap doesn’t transfer any of the germs onto your hands – but then the study was conducted by a us soap manufacturer.

Farmers under pressure to reduce chemical pesticides can take heart from the news that the US Department of Agriculture is about to start trialling a device that can kill insects with a laser. Developed by Seattle company Intellectual Ventures Lab (IVL), the ‘Photonic Fence’ isn’t really a fence at all, but a small box containing lasers, cameras and an AI computer system. The cameras scan the air around the device for 100 metres, and the AI system measures the shape, speed, acceleration and wingbeat frequency of any bugs detected, to establish which are potentially harmful. Any insects identified as a threat can be zapped by the lasers, with a ‘kill rate’ of up to 20 insects per second. By deploying several such devices, farmers could effectively create a virtual fence around their crops that kills harmful pests but leaves bees and other beneficial or harmless insects unharmed. As well as protecting crops, it’s hoped the Photonic Fence could also prove useful in the fight agai...

Do video games affect behaviour? Video games are likely able to affect the way we behave in a number of ways. For instance, there’s concern about whether violence in games makes young people more violent. It’s not uncommon for news outlets to blame games every time a crime happens, but how true is that claim? This is controversial even within the scientific community. Yes, exposure to violence seems to affect the brain, but studies have also found that we’re good at distinguishing between real and virtual violence, and aggressive behaviour is better explained by other, mainly socio-economic factors. Numerous studies about the effects of games on the brain had been published, but all that information had not been put together until now. How did you review the research?  We gathered all scientific articles to date and compared results. In total, we found 116 experiments, the first from the 1980s. Many compared regular video game players with people who had never played; other...

That’s the temperature of your core. Your skin is usually around 34°C, and your face, fingers and toes can be much colder. The receptors in your skin react to differences in temperature, so, when you put your hand on your bare stomach, your hand registers warmth but your belly shrieks ‘cold!’, even though both are ‘skin temperature’. Similarly, the inside of your mouth feels warm to your finger, but not to your tongue.

It won’t make you stronger in the sense of building muscle in your heart or diaphragm, but holding your breath while training for certain sports has been shown to improve the ability of your muscles to cope with short, intense exertions. This works by increasing the concentration of bicarbonate in the blood, which helps to neutralise the lactic acid produced during anaerobic exercise. For this technique to work, you need to exhale normally and hold your breath when your lungs are empty, rather than taking a big breath in and holding that. There are significant risks, though. A 2009 study found that free divers who regularly held their breath for several minutes had elevated levels of a protein called S100B in their blood, which is an indication of long-term brain damage.

Sleep consists of two radically different physiological states. There is rapid eye movement sleep (REM) and non-rapid eye movement sleep (NREM). The sleep stages seem to have different functions, but why we sleep is still not completely understood. Babies spend half of their sleep in REM, but this drops to a quarter by the age of two. It is therefore thought that REM sleep is particularly vital for the developing brain. In NREM sleep, brain activity slows and a person woken at this stage may feel groggy. 1. Pituitary gland During non-REM sleep, the pituitary gland produces growth hormone and secretes prolactin. This counteracts dopamine, to lower general arousal levels. 2. Mouth You produce less saliva, which reduces the need to swallow. Five per cent of adults also grind their teeth at night, mostly during the early stages of sleep. 3. Lungs The throat muscles relax so your airway narrows when inhaling. This can cause snoring, or temporarily halt your breathing for a few ...

Humans need to sweat to survive in warm conditions, and that’s only possible if the combination of temperature and humidity – known as the wet-bulb temperature – stays below around 35°C. According to a 2012 study by scientists at MIT, this limit could be reached globally if our planet warms by around 12°C. Fortunately, few scientists think global warming will do this in the foreseeable future.

You can still have a fairly normal life without one of your lungs, a kidney, your spleen, appendix, gall bladder, adenoids, tonsils, plus some of your lymph nodes, the fibula bones from each leg and six of your ribs. Losing your uterus, ovaries and breasts, or your testicles and prostate, is also quite survivable, although you might need hormone therapy to avoid other long-term problems, such as brittle bones. If you allow yourself artificial replacements and medication, we can go further and remove your stomach, colon, pancreas, salivary glands, thyroid, bladder and your other kidney. Still not enough for you? Theoretically, surgeons could amputate all of your limbs, and remove your eyes, nose, ears, larynx, tongue, lower spine and rectum. Supported by machines in an intensive care unit, they could also take away your skull, heart and your remaining lung, at least for a short while. This adds up to a theoretically survivable loss of around 45 per cent of your total body mass. But a...

Even after passing through water treatment plants, small quantities of chemical compounds from cleaning products can find their way into rivers, ponds and lakes and have adverse effects on aquatic life. Phosphates in laundry and dishwasher detergent have a fertilising effect, triggering the widespread growth of algae that saps away the water’s oxygen, reducing biodiversity. By reducing water tension, surfactants allow other pollutants in water bodies to be absorbed more easily by plants and animals. Many other compounds can be toxic to wildlife, or affect growth and reproduction, for instance by mimicking the effects of hormones in mammals and fish

Talking in our heads is referred to by psychologists as ‘inner speech’. It involves some similar processes to ‘overt’ speech – it recruits brain regions involved in language, such as the Broca’s and Wernicke’s areas, and is even accompanied by minute muscle movements in the larynx. However, there are notable differences too, with brain areas useful in inhibiting overt speech playing a greater role in inner speech. The exact brain mechanisms involved may come down to why we are talking in our heads in the first place. For example, when we read a book, brain regions involved in attention may be more active than when we are mentally preparing for a race.

Beer typically has around 40 calories per 100ml (one pint = 568ml). To get your daily 2,000 calories just from beer, you’d need to drink 11 pints every day, which is hardly healthy. But the alcohol is the least of your problems. Beer, even real ale or Guinness, contains no fat, almost no protein and – crucially – no vitamin C. Without any source of vitamin C, you’ll experience symptoms of scurvy in two or three months and be dead in six.

             Ten endangered languages Kaixána Where: Brazil According to reports from 2006, one named individual spoke this language – though he was 78 years old. patwin Where: USA native to northern california, by 2011 it was assumed that just one person spoke Patwin as their first language. Diahói Where: Brazil Probably fewer than a hundred members of the indigenous people who spoke this language live in southern Amazonas state; a 2006 study estimated that only one actually spoke the Diahói dialect. Apiaka Where: Brazil only a few hundred members of the Apiaká people survive in northern mato Grosso state; having adopted Portuguese, only one person is now believed to speak the language. chaná Where: Argentina/Uruguay in 2005, a man was discovered who spoke at least some words of this language, long believed extinct. Bikya Where: Cameroon in 1986, it was reported that only four people spoke this Bantoid language, only one of t...

10 incredible human Records Longest time breath held  in 2012, stig severinsen of Denmark held his breath underwater for a remarkable 22 minutes. Longest tooth extracted  A tooth measuring 3.2cm long was removed from loo Hui Jing in singapore in 2009. Longest nose  mehmet Özyürek of turkey has the world’s longest nose. in 2010, his proboscis measured at 8.8cm from bridge to tip. Longest fingernails  in 2009, American melvin Boothe’s fingernails were measured at having a combined length of 9.85m. Longest tongue  englishman stephen taylor’s tongue measures at 9.8cm (from the tip to the middle of his closed top lip). Largest hands  American robert Wadlow, the tallest man ever, also holds the record for largest hands – 32.3cm from wrist to fingertip. smallest waist  cathie Jung of the usA has the world’s smallest waist. it measures 38.1cm corseted – and just 53.34cm even without a corset. Longest legs  svetlana Pankra...

the 10 most Widely spoken languages 01Mandarin Chinese speakers: 848m 02 Spanish Speakers: 406m 03 english  Speakers: 335m 04 hindi Speakers: 260m 05 arabic  Speakers: 223m 06 Portuguese  Speakers: 202m 07 Bengali  Speakers: 193m 08 russian  Speakers: 162m 09 Japanese  Speakers: 122m 10 Javanese (Indonesia)  Speakers: 84.3m

Top 10 invented languages esperanto  created by: Ludwik Lazarus Zamenhof in 1887 An international auxiliary language devised with the aim of promoting peace and understanding across the world. solresol  created by: François sudre in 1827 in the language of solresol, words can be communicated using hand gestures, colours and musical notes as well as verbally. Universalglot  created by: Jean pirro in 1868 An early – and unsuccessful – attempts at an international auxiliary language drew on vocabulary from a number of existing dialects. blissymbols  created by: charles K Bliss in 1949 using symbols, this written language was adopted for signs in places like airports in canada and sweden. Slovianski  created by: a team of language experts in 2006 An interlanguage designed to improve communication between slavic peoples. it’s now spoken by around 2000 people. Sambahsamundialect  created by: olivier simon in 2007 this new tongue...