An association between certain sounds and spiky or round shapes, which is common to humans from cultures all over the world, appears to be shared by dogs.

Since 2001, many studies have reported that people are much more likely to give the made-up name “bouba” to a curved shape and “kiki” to a spiky shape. The effect has recently been shown in chicks and possibly , too.

at the University of Parma, Italy, and her colleagues decided to test whether pet dogs have the same tendency.

In the first experiment, 51 owners sat with their adult dogs, holding them during the experiment. They were shown a rounded shape on a panel on one side of the room and a spiky shape on the other. When they heard the word “bouba” 56 per cent of the dogs lingered on the round shape. When they heard “kiki”, 63 per cent concentrated their gaze on the spiky shape.

To make sure the dogs weren’t influenced by their owners, the team repeated the experiment with the owners wearing headphones playing music so they couldn’t hear the words. The outcome was the same, with a slightly stronger bias towards round shapes for the word “bouba”.

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“If animals without human-like language also spontaneously associate sounds with shapes, this suggests that at least some of the mechanisms underlying sound symbolism may not be specific to language,” says Biffi. “Instead, they may reflect more general principles of how the brain integrates information from different senses.”

However, it is unclear to what extent the effect depends on dogs having experience of listening to human speech, or the fact that dogs have co-evolved with humans for thousands of years. To investigate this, Biffi says the team is now collecting data on puppies and wild canids, including foxes, and also wants to see if the effect exists in cats.

“If cats also show the bouba–kiki effect, this would provide further evidence that sound symbolism may reflect general perceptual mechanisms, rather than adaptations specifically related to dogs’ long history of cooperation and communication with humans,” says Biffi.

at Eötvös Loránd University in Hungary says the study suggests the matching of speech sounds to shapes relies on general mechanisms rather than complex linguistic representations. “An exciting next question is to what extent [these links] in dogs arise through statistical learning or more hardwired expectations,” he says.

Big issues abound in this month’s books, as we batten down the hatches against El Niño and the known unknowns out there. Luckily, here in our snug bunker, we have plenty of other things to think about. There’s the source of the next big conflict (it’s probably not what you think), how to eat healthily (as close to definitive as you’re going to get), and fighting talk from inside the rush to develop AI. There’s also the real story of pregnancy loss, giving animals their rightful place, the nature of family, saving childhood, and why humans ask questions. Oh, and there are some silly sums and extraordinary fantasy botanicals for those who fancy a spot of fun. Lovely.     

by Kevin Roose

Just in case you’ve been living in an off-the-grid shack next to a beautiful lake for the past few years, The AGI Chronicles looks like an essential re-entry book before returning to, er, civilisation. The clue’s all over the subtitle, “The inside story of the race to create an artificial superintelligence”, and author Kevin Roose is tech columnist for The New York Times, so he ought to know – a lot. New Scientist will be reviewing it soon in depth, but meanwhile, this zeroes in on the past decade’s efforts by a few companies fighting to build the “most powerful technology in history… artificial general intelligence (AGI) – a computer system capable of outdoing humans at almost anything”. Expect a fat volume (an alarming 448 pages, says the book’s website), based on “more than 150 interviews with insiders at OpenAI, Anthropic and Google DeepMind, as well as unpublished company documents and research memos”. It will be fascinating to see what our reviewer makes of the book. Just don’t drop it on your foot, OK?

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by Tom Crawford

There’s a small band of mathematicians (think Matt Parker, Alex Bellos, Hannah Fry and Eugenia Cheng) who somehow manage to make a tough subject engaging, exciting or, whisper it, even funny. Tom Crawford’s title is certainly enough to raise a guffaw in the hardest of hearts, let alone Pokémon fans. Now try asking, as the publisher does, how many daily calories you would need to feed a Charizard. Could the Death Star’s laser actually blow up a planet? What is the half-life of the Incredible Hulk? And is the meaning of life really “42”? OK, we know the answer to the last question, but it does sound like Crawford is pulling out all the stops to use his Oxford fellow smarts on the fantasy maths of fictional, often wild, universes. Parting shot: just how would you work out Frodo Baggins’s life insurance premium for the journey to Mordor?

Primatologist Frans de Waal, who died in 2024, left a huge legacy for other scholars and campaigners fighting ideas of human exceptionalism and arguing that animals have complex inner lives. Minds I’ve Met is one of two books by de Waal posthumously published this year; the other is , a selection of photographs taken during his work over 30 years, showing, say the publishers, “the rich social life” of the primates he studied. Both books sport the provocative and sometimes moving titles de Waal used to challenge the status quo (think , Mama’s Last Hug, or ). In Minds, the kicker is also in the subtitle: “From denying to embracing the inner lives of animals”. The publishers say his “pioneering work… contributed to a new image of animals as intentional agents with minds of their own, capable of remarkable cognitive feats, demonstrating empathy and self-awareness, showing emotions and conscious”. He often wrote for and talked to New Scientist. If he’s new to you, you could do worse than starting here.

by Paris Marx

Forget, for a moment, grappling with AI conceptually and think about it as an environmental issue. All over the world, the data centres already built and those planned are crucial to the current AI successes and to the ambitions of the companies involved. What’s more, say the publishers of a polemical book called Hyperscale, the centres use up resources such as water and power at “dangerously unsustainable levels”. This book’s author is Paris Marx, a tech critic, journalist and host of the Tech Won’t Save You podcast. It sounds like a wild ride, with the publishers saying the “tech overlords are waging a resource war as they trade our future for their profit”. It is nothing less than a “civilisational time bomb in the making”, where tough reporting shows that “the greatest threat is not the spectre of AI, but a global disaster that has already begun”. The book is already longlisted for this year’s .

by Christopher Gardner

The sheer amount of advice on what to eat to be healthy is unnerving, especially since a lot of it is quite probably junk. But before you reach for a doughnut out of sheer despair, there are books out there that offer sane ways through the morass, with excellent science and tasty-sounding recipes. Food Sense is by Christopher Gardner, who’s been researching nutrition and health for decades, and is now the director of nutrition studies and a professor of medicine at Stanford University in California. His publishers promise that he “shows you where there is genuine scientific consensus so you can discern fact from fads and ignore the health food marketing hype. From weight loss to protein, ultra-processed foods, seed oils, GMO’s and fermented foods, this definitive and myth-busting guide answers all your nutrition questions”. Now there’s a big claim or two. Luckily, former New Scientist staffer (and all-round nutrition, health and longevity specialist writer) Graham Lawton is on hand to review the book later this month so we’ll find out how well they all stack up  – that, and how good the recipes are.

by Tania Lombrozo

Why are the clouds white? What made that artwork so special? Where does the cat vanish to at night? Who am I? From the existential to the trivial, questioning – curiosity and the seemingly endless desire for answers – feels hardwired in us. So, is it? And does it connect evolutionarily to the human way of learning? Could it even be that elusive thing that makes humans, human? Certainly, the subtitle of Tania Lombrozo’s new book –  “The science of explanation and the human drive to understand” – tells us where she thinks we are. She is a professor of psychology at Princeton University, and her research, say her publishers, is all about turning our explanation seeking back on itself by asking, ”What does explanation do for us? And, most important, how can we do it better?” The idea that some explanations are more satisfying than others also sounds intriguing.

by Cherry Casey

Have childcare and education in the UK been turned into a business – and if so, who is profiting? Certainly not the children, argues Cherry Casey, a journalist specialising in children’s rights. Her book comes billed as an “exposé of how chasing profits and league tables has come at the cost of developing well rounded, happy people”. As ever, the book’s subtitle positions her quest: “How we turned children into data and why we need to stop”. It’s an interesting argument, given the rise of mental illness even in young children and the overall datafication of our world, and the use (or overuse) of testing and “zero-tolerance” behaviour policies many schools advertise as a desirable end. So, who is profiting, and how do we turn the ship round?

by Kate Clancy

This looks to be a moving but probably also essential book, dealing with the realities of one of life’s most important but common events: the loss of a pregnancy. The author is Kate Clancy, a professor of anthropology at the University of Illinois, Urbana-Champaign, where she’s based in the Department of Gender and Women’s Studies and the Program in Ecology, Evolution, and Conservation Biology. This is likely to give her book the kind of heft it needs to challenge the myths surrounding pregnancy loss. According to its publisher, Clancy “makes an impassioned, fact-based case for truthfulness and care at a time when inaccurate images of fetuses abound, electronic impulses continue to pass for a heartbeat, and reproductive autonomy is criminalized”.

by Elisabeth Braw

Where the next war will come from is a question that keeps many of us awake at night – not to mention political analysts and defence chiefs fully occupied. One place you would be unlikely to guess is the bottom of the sea. But that is where an extraordinary-sounding book is set. A quick peek confirms that the book looks to deliver on its publisher’s description as a “gripping account of the hidden battles beneath the world’s oceans, where cables and pipelines – the lifelines of the modern world – are under constant threat from states, corporations, and hackers”. And remember, the stakes could hardly be higher at a time when so much global traffic – internet, energy, telecoms – runs through cables that are out of sight. Braw is a force to reckon with: she’s a senior fellow at the Atlantic Council, where she leads the Threats to the Global Maritime Order initiative. She was previously a senior research fellow at the Royal United Services Institute and is also a member of the UK National Preparedness Commission.

by Alison Flood, illustrated by Emma Tudor-Bloch

Here’s some fun – a chance to join New Scientist’s own Alison Flood (sidenote: this is included here without any pressure or suggestion from her…) on a strange voyage into the fictional botanical worlds created by authors drawn from the ranks of science fiction and fantasy. Published in association with the Royal Botanic Gardens Kew, it comes with over 100 beautiful (if occasionally scary) illustrations by artist Emma Tudor-Bloch, vividly bringing to life all manner of unreal plants and fungi. And for those seeking a bit of heft, there’s expert text and historical images from Kew’s experts, exploring the real-life plants and fungi that inspired the fantasy. So, watch out for a host worlds including nightlock (The Hunger Games, Suzanne Collins), weirwood trees (A Song of Ice and Fire, George R.R. Martin), Ents (The Lord of the Rings, J. R. R. Tolkien), redweed (The War of the Worlds, H.G. Wells), wheel trees (The Amber Spyglass, Philip Pullman) and the Cordyceps fungus (The Last of Us).

by Meredith Small

Mother. Father. Son. Daughter. Grandmother… Most of us grow up in a family of some sort, no matter how dysfunctional. But Family: How the human need for belonging shapes our lives by Meredith Small is no self-help book. Small is a well-known anthropologist at Cornell University in New York state, and the author of Our Babies, Ourselves. Here, say her publishers, she sets out to examine the roots of the family and why this type of connection is the bedrock of human interaction in all cultures – and how getting to grips with its nature might help us “navigate our rapidly changing world”. Given the sometimes overemphasis on the family and “family values” globally, some might argue we should join Small as she asks why we form families and place such importance on family relationships, and whether family life does deliver – throughout our different stages and ages. As you would expect from an anthropologist, Small’s time frame spans millions of years and her scope is global – all human life and setup is here, promises the publisher. From a peek, it looks like family is as varied as the human experience. Lots of room for manoeuvre, thankfully.

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Like many people, I spend much of my time at home fantasising about my next holiday. During the trip itself, most of my stresses seem to melt away, and I return feeling optimistic and energised.

Each time, I am determined to integrate those feelings into my day-to-day life, but I am almost invariably disappointed. Within a couple of weeks – sometimes less, depending on how much time I have to spend on the London Underground – I become the same irritable and frustrated person that I always was. And so, I start dreaming about my next escape.

As I planned a recent trip to Madrid, I wondered whether I was foolish to hope that my travels would offer anything more than temporary relief.

Delving into the psychological literature, though, I was relieved to see that the answer is a resounding no. Growing evidence explains the specific ways that our holidays can increase our wellbeing and, crucially, the types of activities that will offer the greatest restoration, based on the ancient Greek principle of eudaimonia: “human flourishing”.

“Instead of thinking only about where you are going to travel, you can think about what psychological experience you want the vacation to provide, and try to create that experience,” says , a psychologist at the University of Amsterdam in the Netherlands.

A serious consideration of holiday psychology has been a long time coming: until recently, psychologists studying wellbeing had mostly focused on the benefits of relaxation and leisure activities more generally. There have been plenty of , for instance, while the research on vacations was patchy. As a result, they failed to capture the distinct opportunities for a mental reset that holidays can afford away from the daily grind. “From a psychological perspective, that separation is quite important,” says Yan.

°ä´Ç˛Ô˛őľ±»ĺ±đ°ůĚý, published last year. Analysing the results of 32 different studies,  at the University of Georgia has shown that the average mood boost begins before we have even left home, as the anticipation of a trip builds. Those good feelings remain highly elevated for at least 21 days after we have returned home and may not return to the baseline for a further three weeks.

If you, like me, struggle to feel those longer-lasting benefits, it may be because you have been focusing on the “wrong” kind of happiness. Behavioural scientist at the University of St Andrews Business School in the UK argues that we should distinguish between hedonic wellbeing, which concerns enjoyment and pleasure, and eudaimonic wellbeing, which concerns “personal growth, sense of purpose and meaning”.

“On holiday, hedonic wellbeing might come from lounging on a beach, enjoying nice food or staying in a lovely hotel,” he says. “Eudaimonic wellbeing might come from the sense of achievement in completing a challenging hike, learning about a new culture or forming connections with fellow travellers.”

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, McLean and his colleague at King Faisal University in Saudi Arabia found that the boost in hedonic wellbeing faded pretty quickly, whereas the eudaimonic feelings lingered for at least eight weeks. For this reason, he recommends planning holidays that combine both elements – pure relaxation alongside the kinds of activities that feel more purposeful.

Yan agrees. “Travel can also expose people to novelty, different cultures, new activities and different versions of themselves,” she says – and it is here that the biggest benefits lie. “These experiences may help people not only feel rested, but also feel more alive, connected and reflective.”

So, what can we do to achieve it? Based on the available research on both hedonic and eudaimonic wellbeing,  to think about (see below).

You don’t have to include every single element, but you may benefit from reflecting on the list and deciding which are most significant to you. “For example, if relatedness is very important, you might want to prioritise meaningful time with family, friends or a partner, rather than trying to do too many activities,” says Yan. To maximise autonomy, “it helps to build in freedom and flexibility”, she says. “A vacation that is too tightly scheduled can become another source of pressure.”

Mastery, meanwhile, might involve attending an art class or learning to scuba dive, and the need for novelty might encourage you to try to experience a whole new culture, rather than returning to a familiar destination.

That may take more serious attention than you currently pay to your travel plans. “Do not treat vacations only as time off. Think about what kind of psychological needs the vacation can satisfy,” says Yan. The hard work may pay off immediately. “Our research showed that merely anticipating an upcoming vacation can boost wellbeing, so the planning and looking-forward phase has value in itself,” says McLean. “It’s better to book early!”

If you are worried about protecting your purse strings, rest assured that you can glean many of these benefits from shorter trips – in fact, the . Nor do the activities have to be exceptionally luxurious: in Grant’s meta-analysis, physical exercise proved to be one of the best predictors of enhanced wellbeing, and that can be achieved through long walks or visits to outdoor gyms.

You may not even have to leave your home city, provided that you take those psychological needs seriously enough and don’t simply spend the time catching up on other responsibilities. When planned correctly, taking some time off at home can still be beneficial, says Yan. “For example, people can create boundaries around work, avoid routine chores during the holiday period, try new local activities, spend quality time with others, visit nearby nature or create small rituals that make the time feel different from ordinary life.”

Whether you are travelling abroad or staying at home, you should try to find ways to immerse yourself in the memories of the experiences after your break has ended. Along these lines, McLean also found that using virtual-reality headsets to return to the location of their holidays significantly prolonged the wellbeing benefits experienced by his study participants.

We can’t all afford this technology, of course, but he suggests some lo-fi alternatives. “Deeply engaging with holiday memories – perhaps through journaling about the experience in vivid detail, creating a rich photo or video montage that you actively revisit, or even planning a return trip to the same destination – might tap into similar psychological pathways, though this would need further research to be confirmed.”

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“The underlying factor is about re-engaging psychologically with the vacation experience in a rich, immersive way,” says McLean. You are unlikely to get this from passively scrolling through your photos; it needs your full attention.

Attempting to put all this into practice on my trip to Madrid, I made a greater effort to chat to locals in Spanish, maximising my sense of autonomy and mastery; attended a concert by one of my favourite singers, an experience that was imbued with meaning; and visited the city’s botanical gardens, which helped me connect to nature.

It has now been six weeks since I returned, and the warm glow remains. My sunnier mood may be slowly fading, but it hasn’t yet been extinguished. Now, I’m dreaming of my next trip.