Why Do Most Languages Have So Few Words for Smells?

And why do these two hunter-gatherer groups have so many?

Describe a banana. It's yellow, perhaps with some green edges. When peeled, it has a smooth, soft, mushy texture. It tastes sweet, maybe a little creamy.

And it smells like... well, it smells like a banana. 

Every sense has its own “lexical field,” a vast palette of dedicated descriptive words for colors, sounds, tastes, and textures. But smell? In English, there are only three dedicated smell words—stinky, fragrant, and musty—and the first two are more about the smeller's subjective experience than about the smelly thing itself.

All of our other scent descriptors are really descriptions of sources: We say that things smell like cinnamon, or roses, or teen spirit, or napalm in the morning. The other senses don't need these linguistic workarounds. We don't need to say that a banana “looks like lemon;” we can just say that it's yellow. Experts who work in perfume or wine-tasting industries may use more metaphorical terms likedecadent or unctuous, but good luck explaining them to a non-expert who's not familiar with the jargon.

Some scientists have taken this as evidence that humans have relegated smell to the sensory sidelines, while vision has taken center-field. It's a B-list sense, deemed by Darwin to be “of extremely slight service.” Others have suggested that smells are inherently indescribable, and that “olfactory abstraction is impossible.” Kant wrote that “Smell does not allow itself to be described, but only compared through similarity with another sense.” Indeed, when Jean-Baptiste Grenouille, the protagonist of Perfume: The Story of a Murderer can unerringly identify smells, remember them, and mix and match them in his head, he seems disconcerting and supernatural to us, precisely because we suck so badly at those tasks.

But not all of us. In Southeast Asia, there are at least two groups of hunter-gatherers who would turn their noses up at this textbook view. Asifa Majid from Radboud University in the Netherlands has found that the Jahai people of Malaysia and the Maniq of Thailand use between 12 and 15 dedicated smell words.

Want to learn faster? Stop multitasking and start daydreaming

Neuroscientist Daniel Levitin explains how students can avoid letting social media and multitasking ruin their study time.

Information is being created and disseminated faster than any of us can absorb it. Google estimates that humans have created more information in the past five years than in all of human history - 300 exabytes of information (300,000,000,000,000,000,000) to be precise. If all that information were written on 3x5 index cards, your personal share of it would wrap around the earth twice. The pile of cards would reach to the moon three times.

Social media, emails, texts, WhatsApp messsages and phone calls take up an increasing amount of time. Our to-do lists are so full that we can’t hope to complete every item on them. So what do we do? We multitask, juggling several things at once, trying to keep up by keeping busy.

Research by Earl Miller of Massachusetts Institute of Technology (MIT) and others however shows that multitasking doesn’t work - simply because the brain doesn’t work that way. If you’re studying from a book and trying to listen in on a conversation at the same time, those are two separate projects, each started and maintained by distinct circuits in the brain. Pay more attention to one for a moment and you’re automatically paying less attention to the other. 

To make matters worse, learning information while multitasking causes the new information to go to the wrong part of the brain, as shown by Russ Poldrack of Stanford. If students study and watch TV at the same time, for example, the information from their course work goes into the striatum, a region specialised for storing new procedures and skills, not facts and ideas. Without the distraction of TV, the information goes into the hippocampus, where it is organised and categorised, making it easier to retrieve it. 

“People can’t do [multitasking] very well, and when they say they can, they’re deluding themselves,” says Miller. And it turns out the brain is very good at this deluding business.

How to teach ... cold and flu

From making cuddly bacteria to lessons on Louis Pasteur, here’s our guide for teaching your students the basics of avoiding the dreaded lurgy.

Winter brings lots of wonderful things – a new year, snow, the chance to break out your scarf collection. But they are all doomed to arrive during the most disgusting time of the year: cold and flu season. For those in schools, each day brings a chorus of other people’s coughs and sneezes, and a gauntlet of germs to dodge. So how can you teach your students the basics of staying healthy?

Primary

For key stage 1 pupils, this three-lesson module – linked to the science and personal, social and health education (PSHE) curriculum – from Share Good Times Not Flu offers a simple overview of what it means to be healthy and how exercise, diet and hygiene can help your young charges stay that way. A key stage 2 version, also made up of three lessons , goes into greater detail about how germs enter the body through coughs, sneezes and unwashed hands, and how good hygiene practices can keep them out.

This resource pack from e-Bug offers a variety of fun ways to look at germs and microbes, including yeast races (exploring how microbes cause dough to rise), an experiment to see how far germs can spread through handshakes (using glo spray), and a toothbrushing tracker to highlight the importance of oral hygiene.

This guide to preventing the spread of bugs through handwashing, also from e-Bug, uses quizzes, colouring and a bowl of water and pepper (yep) to teach pupils the power of soap and water. And you can decorate your classroom with this accompanying poster to reinforce the message.

This US guide provides more puzzles, word searches and songs (“If you’re happy and you know it, scrub your hands!”) to ensure your little ones remember to clean their mitts, whileHygiene4Health offers a variety of resources on the topic, including this poster explaining the principles of good hand hygiene.

The eco guide to packaging

Make your zero tolerance stance on unecessary packaging known: it's the best way to stop it.

In the mid-noughties my inbox was full of images of shrinkwrapped fruit and veg: readers were incensed that supermarkets wrapped coconuts (which famously provide their own husks) with layers of non-recyclable film. The debate has been repackaged for a new generation. Twitter is awash with examples of idiotic packaging from e-tailers, such as one bottle of nail varnish and a cat’s toy, each sent in a big box.

We accumulate 200kg of packaging materials a year per person, adding up to almost 13m tonnes entering the UK waste stream. Even if you drag your cardboard to the recycling plant, you’re still complicit in a system that wastes important resources on a single-use box. It’s also cheaper to have one size of box that fits neatly into a truck. Logistics companies don’t get charged for shipping air, creating more carbon emissions and traffic. The protective packaging industry that makes crumpled paper and inflatable plastic pockets is a real winner, projected to be worth $35bn by 2020.

If you want to do something practical, report outrageous over-packaging (where the product takes up less than 10% of the volume of the packaging) to your local trading standards officer. A former officer tells me that they’re particularly hot on the issue of shipping air in huge, unnecessary boxes, because part of their mandate is to keep delivery traffic to a minimum.

Amazon, though often named and shamed, seems keen to hear reports of packaging frustration and is working with German researchers to make its deliveries eco-friendly.

In the past the packaging industry avoided closer control by arguing that lavish packaging was demanded by the consumer. But it makes it harder for the industry to use this defence if we all continue to Instagram our discontent.

Who are the homeless and how do we count them?

For the thousands of people who are sleeping on the streets or are in temporary accommodation, winter is one of the hardest times of the year. Being able to provide relief during this period depends, at least in part, on understanding how many people are affected by homelessness – and who they are. Unfortunately, that’s not straightforward.

In the UK, a person is legally defined as homeless if they have accommodation but can’t reasonably be expected to occupy it, or if they don’t have any accommodation at all. This definition covers a broad range of circumstances – from those who can’t afford to pay rent, to those forced to leave home, for whatever reason. But the first thing to know is that there’s a big difference between the number of people who the state recognises as homeless and how many people actually are. This is known as the distinction between the “statutory” homeless, and the “non-statutory” or “single” homeless.

The “statutory” homeless are those who apply to local authorities as homeless, and are accepted as such. People are only accepted if the council deems that they are eligible for housing support, or can be classified as being “unintentionally homeless” or in “priority need”. Information on statutory homelessness is readily available. All local authorities are required to report on the number of statutory homelessness applications received (and “acceptances” made) to the government on a quarterly basis.

In England, between April and June 2015, 13,850 households were accepted as homeless – an increase of 5% compared with the same quarter in 2014. Few of these households will have been without a roof over their heads. Rather, their circumstances can be considered an indicator of housing stress, as a result of relationship breakdown or over-crowding, for example.

“Single” homelessness refers to individuals without dependents, who are not entitled to accommodation from local authorities. Some of these are visible on our streets – in autumn 2014, the official rough sleeping estimate was 2,744, up 14% from 2013. But most remain out of sight – “hidden” in bed and breakfasts or squats and on the floors and couches of friends and family. There is no effective or robust mechanism to monitor “single” homelessness, so these people are largely absent from government statistics. Our best estimate is that there were 2.23m single homeless people in England, in 2013.

Three ways teachers can wind down effectively after a long term

The Christmas break is finally here, so how can teachers make sure they leave work in the classroom? Neurologist Judy Willis shares her advice.

The countdown has begun for many teachers who eagerly anticipate a well deserved and much needed Christmas break.

It may surprise you to hear that there is a neuroscience behind effectively switching to rejuvenation mode. Just as your brain’s memory strengthens with practice, so do your brain’s behaviour control networks. Essentially, what this mean is that teachers get used to patterns of behaviour – such as thinking about their pupils before themselves – during term time which can be hard to break over the holidays. However, it’s important to switch off. So to help you I’ve put together a few tips on how to do this.

Make a list and check it twice

Write down all the things you’ve promised yourself to get done during the break. This could include organising things you’ve put off – cleaning your desk and arranging the photos on your phone into albums on your computer. It might also include getting together with people you’ve had to put off during the term or sending thank you cards to students and families. Other top festive tasks include pre-making any holiday food or buying gifts for family and friends.

To care for your brain and body during the school break any demands that are put upon us need to be managed. Your behavior control centres are located high up in your brain’s prefrontal cortex. These neural networks send messages to the brain directing the desired physical actions or emotional responses. The system works well until stress builds up and blocks the behavior control messages flowing from cortex to brain. This means that knowing what you have to do stops you from stressing out.

What can science tell us about the Star of Bethlehem?

During winter it can sometimes feel that the whole day passes in the blink of an eye and that evening darkness comes far too quickly. While more daylight would be a lovely thing, the early darkness has one big advantage: the stars. On a clear evening you can look up and see far into space. I’ve spent many winter evenings with my children, on our way home from activities, looking for Orion (and other constellations), following its path through the seasons.

Stars and space are two of the most popular science topics, whatever the age of the child. There’s something awe-inspiring and beautiful about looking into the night sky at the stars.

But it isn’t just children and young people who are fascinated by stars – astronomy is one of the few sciences where amateurs can make a significant contribution to our understanding of the subject.

… and there came from the East

At this time of year, the Christmas story can serve as a reminder that, throughout history, people have looked at the night sky, and wondered about what they have seen. The Babylonians had star catalogues as early as 1300 BC which contained information about constellations and patterns in the stars. It’s likely that the observation and naming of these constellations went back before that date.

The stars and constellations were important to those observing them. According to biblical tradition, after Jesus was born, magi (or wise men) from the east came to find Jesus saying that they had seen his star when it rose and followed it. The magi were people who studied the stars and saw significance in them.

How anxiety scrambles your brain and makes it hard to learn

Levels of stress and anxiety are on the rise among students. Juliet Rix has tips to control the panic and thrive academically.

Olivia admits she’s always been a worrier – but when she started university, her anxiety steadily began to build. One day she was simply too frightened to leave the house. For two weeks she was stuck indoors, before she was diagnosed with generalised anxiety disorder and began to get the help she needed.

With support from her GP and university wellbeing service, and courses of cognitive behavioural therapy (CBT), she was able to stick with her university course and to start enjoying life again.

But Olivia is far from alone in her anxiety: the number of students declaring a mental health problem has doubled in the last five years, to at least 115,000.

“And that is a very small proportion of the students who are having mental health difficulties,” says Ruth Caleb, chair of Universities UK’s mental wellbeing working group.

A study of UK undergraduates has found that even among students symptom-free before starting university, some 20% are troubled by a clinically significant level of anxiety by the middle of second year.

What does anxiety do to students? It causes the body to prepare itself for fight or flight.

“If you are in a situation of imminent actual threat, then the increased alertness and body response can be lifesaving,” explains Chris Williams, professor of psychosocial psychiatry at the University of Glasgow, and medical advisor to Anxiety UK.

“But if it occurs when trying to revise, or present a talk, or at such a high level that it paralyses or causes errors, it can interfere with what we want to do.”

How to discipline your children without rewards or punishment

Many parents are moving towards “gentle parenting”, where they choose not to use rewards (sticker charts, lollies, chocolates, TV time as “bribes”) and punishments (taking away “privileges”, time-out, smacking) to encourage good behaviour, but encourage good behaviour for the sake of doing the right thing.

Gentle parents argue that to offer rewards and punishments overrides a child’s natural inclination towards appropriate behaviour by teaching them to behave in certain ways purely to receive a reward, or to avoid punishment.

What is discipline?

For most people it would seem impossible to discipline without rewards and punishments. However, it depends on your understanding of “discipline”. Discipline always has a silent “self” in front of it because it’s about controlling yourself.

So, in the case of parenting, it’s about helping children learn to manage themselves, their feelings, their behaviour and their impulses. We want our children to develop a sound moral compass, to sort behaviours, impulses and feelings into “appropriate” and “inappropriate” and be able to justify judgements about their choices.

When the term discipline is used, it is often in a sense that implies punishment. This meaning is implied because discipline is associated with a behaviourist view of how humans learn. Behaviourism is associated with conditioning, a process whereby learning is an association between behaviour and good or bad outcome, just like in Pavlov’s dog experiment.

However, behaviourism is used less and less because human behaviour is seen as more complex than a simple rewards/punishments model suggests. Behaviourism is also problematic because it implies people behave in desirable ways only to secure rewards or minimise punishments.

We don’t want our children to behave in a way that’s desirable just because they might get something or get into trouble if caught. We want our children to do the right thing because they know it’s right, and because they want to do right.

Motivating children intrinsically not extrinsically

Behaviourism teaches children to look for external motivations to behave in a desirable way. It has been said that rewards and punishments override a child’s natural inclination to do the right thing because they rely on extrinsic (external things that are used to motivate us) rather than intrinsic (a motivator that is internal and usually a feeling of well-being that comes over us when we choose to do something) motivators.

This 78-page book on physics is selling more copies than 'Fifty Shades of Grey'

Since it was published last September, Carlo Rovelli's book, "Seven Brief Lessons on Physics," has sold more copies in Rovelli's native country, Italy, than E.L. James' smash hit "Fifty Shades of Grey," The Spectator reported.

And the English translation has quickly risen to become Penguin's fastest-selling science debut in the publishing company's history.

So what's Rovelli's secret?

After all, it's not like physics is a topic that people flock toward. In fact, physics has been the least popular STEM (science, technology, engineering, and mathematics) major for US undergraduates since the late '60s.

For starters, Rovelli is an expert on the topic.

He's a theoretical physicist by profession with a focus in quantum gravity — a field that attempts to join the greatest two theories in history: Isaac Newton's theory of gravity and Albert Einstein's general theory of relativity.

Rovelli is also an avid writer of popular science, so he has a habit of transforming complex ideas into clear, simple concepts.