A nondescript 115-million-year-old fragment of leg bone has yielded spectacularly preserved red blood cells, which may be the earliest ever found in dinosaurs.

Red blood cells have previously been found in dinosaur remains, including 75-million-year-old bone fragments collected in Canada in 2015 and the femur of a Tyrannosaurus rex that died 68 million years ago, found in Montana in 2005.

Now, at Curtin University in Perth, Australia, and her colleagues say they have isolated the oldest-ever dinosaur red blood cells from the hind-limb of a theropod dinosaur, Aratasaurus museunacionali, found in Brazil in 2008.

The Aratasaurus individual studied by the team wasn’t yet fully grown, with an estimated body length of just over 3 metres, and weighed about 34 kilograms.

“The fossils we worked on are not display specimens by any means, so they don’t look very interesting,” says Grice. “If you look at them, you think there’s just a bunch of bones and there’s probably not much in there.”

Grice cut thin sections of bone, mounted them onto glass slides and used hydrochloric acid to remove surrounding rock – and she was shocked at what she saw.

“I was jumping up and down,” says Grice. “I ran up to my head of school’s office and was so excited that he gave me a whisky to calm me down. No one has ever seen dinosaur red blood cells in high resolution before.”

The cells she found were abundant: in a single slide, just a fifth of a millimetre wide, there were 20 blood cells. All of the cells were within fossilised blood vessels, providing further evidence that they really were red blood cells.

Liquid chromatography–mass spectrometry analysis revealed the presence of haem B, a constituent of haemoglobin that binds to oxygen, adding molecular evidence of the type of cell.

The team also had to rule out the possibility of any contamination, especially from the sediments in which the fossil was preserved, which were dominated by algae.

The cells found outside the bone were dominated by chlorophyll-derived compounds, whereas those inside contained haem-derived molecules, which strongly suggests that the latter cells weren’t a result of contamination.

The researchers also compared the blood cells to those of the closest living relatives of the dinosaur fossil, birds and crocodiles. The Aratasaurus red blood cells are significantly larger. This could indicate that the cells swelled during fossilisation, or that the species grew much bigger than the fossilised specimen.

at the Natural History Museum in London says previous studies reporting red blood cells in fossils tens of millions of years old are contentious, with some researchers suggesting they could be the result of bacteria or artefacts of the fossilisation process. “This paper is further evidence that fossilised soft tissues such as red blood cells can preserve over geological timescales,” she says.

Grice says the discovery may mean that other nondescript dinosaur fossils that have been locked away in museum collections may hold profound secrets. “There’s drawers and drawers of fossil material, which don’t look very nice,” she says. “This kind of work opens up a whole new opportunity to unlock those collections and bring modern technology and molecular techniques to these specimens.”

As seasonal storms take many of us by surprise, it’s time to head for the certainty of indoors, and a decent book (or two). We have some really intriguing titles this month, including a profoundly odd-sounding book by a forest that shares author rights with humans, and some terrifying night terrors that may teach us a lot about our brains. Oh, and if you want to stop trying to control everything around you, try surrendering to a higher power – of your choice, naturally.

by Anna Lembke

In a complex world, the pressure to control your life is immense: from removing annoying noises around you to slavishly avoiding missing out on living your best life, to keeping your relationship, children and health on track in every way imaginable. It’s overwhelming. Surely we can’t keep it up? According to Anna Lembke’s new book, Radical Surrender: Letting go in a world addicted to change, there is a way out. The word ”addicted” in the subtitle offers a clue here: this is the author of the bestselling book Dopamine Nation, in which she looked at pleasure and pain – and the critical task of finding a delicate balance between them, especially in an age of unprecedented high-reward, high-dopamine stimuli, mostly delivered digitally.

In this new book, we are promised tools to help us let go of our desire for control, but we have to follow Lembke’s advice and acknowledge a “power greater than ourselves, however we define it, and give our will over to that power: less mastery and more a return to mystery”. As an addiction medicine psychiatrist and head of Stanford University’s Addiction Medicine Dual Diagnosis Clinic in California, this “radical surrender” should be scientifically argued. Watch out for our review on 5 November.

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by Steven Strogatz and Alex Townsend

Let’s face it: our every move, from our next Google search to our latest Netflix selection, is utterly dependent on numbers, and AI is now an everyday reality. We have no choice but to face up to the overwhelming presence of mathematics, small, medium – or big. In Big Math: The hidden codes that run our world, Steven Strogatz and Alex Townsend (both leading mathematicians at Cornell University, New York) set out to show how relatively familiar concepts such as matrices, vectors, Markov chains, linear algebra and the like lie at the heart of computer science and quantum computing – essential for us all to know, say its publishers, if we’re to “comprehend the changes sweeping the world”.

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by Amy Crawford

For some while now, we’ve known that the story of invasive species is complex, but just how complex is the stuff of Amy Crawford’s Undesirable: Invasive species, humans, and where we all belong. Blundering all over the world, we have accidentally (as well as deliberately) carried species with us on our adventures – and often created great incidental damage to the recipient environments, ranging from destroyed habitats to changes in the climate. Then there is the accidental introduction of blow-in species over relatively short stretches of water, or those dropped by migrating birds. After hundreds of years, it’s still not entirely clear where the gains or losses to local biodiversity really land.

“Whether it’s garlic mustard spreading through American forests or brushtail possums allegedly decimating the flightless birds of New Zealand,” Undesirable is a “multi-faceted story”, say its publishers. On top of that, exactly how to hold ourselves to account remains an open question. And apparently, the young field of “invasion biology” has been “wracked by controversy and haunted by ethical quandaries as it has sought to destroy some species for the benefit of others”. Crawford, a freelance writer and long-time contributor to Smithsonian magazine, looks set to give us plenty to chew on here.

by Robert Macfarlane, Cosmo Sheldrake, Giuliana Furci, César Rodríguez-Garavito, Los Cedros Cloud Forest. Illustrated by Paula Terán Ospina

Look closely at the list of creators on the cover of this book, aimed at a 5+ age group, about a cloud forest within the Intac valley in northwestern Ecuador, and along with nature writer Robert Macfarlane and other experts, you’ll spot a more unusual contributor: Los Cedros Cloud Forest itself. As the publishers (probably correctly) point out, this is the first time a forest has been included in the creation of a book. To celebrate that fact – and the anniversary of a court decision recognising Los Cedros’s right to exist and flourish in the future – this is apparently “more than a book”, in that by making it, “we are recognising the forest’s moral rights as the co-creator of a literary work”. When you open Song of the Cedars, the flora, fauna and fungi of Los Cedros Cloud Forest jump off the page in a panoramic scene, which can be read or displayed as you wish. All the royalties from sales of the book, the publishers say, will be used to support the protection of Los Cedros. Fighting talk!

by Angèle Christin

What’s it like to make your money as a content creator? Angèle Christin, a digital studies scholar at Stanford University, California, takes us inside that world in her new book. The things these influencers post on social media range “from dance routines to political commentary, makeup tutorials to carpentry DIY”. She looks far and wide to explore what she calls their “golden dreams of passion, autonomy, and monetary returns”. No spoiler alert needed: the outcome for these creators and their followers shows how this digital work tends to fuel precarity, inequality – and much more. Christin’s bottom line: it’s more than time to rethink the economic structure of social media.

by Ashley Ward

Ocean water is nearly four times saltier than human blood, yet it has been central to our evolution – the  “amniotic fluid of life itself”, as the publishers of Saltwater: A natural history of the sea describe it. In this book, author Ashley Ward, a marine biologist, will bring readers face to face with the deep secrets of marine life. There will be jousting rival humpback whales, and claustrophobic journeys in a submersible to 600 metres deep to see an aurora of bioluminescence. We will also apparently encounter the complex seabird cities that develop along coasts, where auk fathers train their chicks to become skilful divers. And there’s mention of the ethereal song of a pod of belugas carrying across a fjord in the Arctic archipelago of Svalbard. Ward could hardly be better placed to deliver all this and more, given his background as a biologist at the University of Sydney, Australia, and as head of its Animal Behaviour Lab.

by Baland Jalal

A sneak peek at the introduction of Baland Jalal’s The Phantom Mind: Insights from the borderlands of sleep shows what we can expect from a researcher often billed as the leading expert in sleep paralysis. “One morning in my teenage years, I awoke gripped by terror… In horror, I realized a demon was on my bed. It grabbed my legs and began tossing them up and down in the air, while crushing my chest and squeezing my neck. While being strangled to death, I could somehow telepathically read the mind of the monster. It had one – and only one agenda: to destroy me.”

This terrifying no man’s land between REM sleep and wakefulness became the territory of his research for the next decade or so. There are plenty more great stories in this highly accessible book, including one featuring Jalal’s mentor, the eminent neuroscientist V.S. Ramachandran, who appears as a sleep-paralysis ghost to Jalal – and leads him off on a new train of thought about exactly how the ghostly figures people see in sleep paralysis are formed. The borderlands of sleep turn out to be a rich seam to mine for those hoping to discover more about the waking mind. And watch out for our interview with Jalal, in our 14 November issue.

by Erica McAlister, illustrated by Natalie McIntyre

This is the latest in the Chicago University Press’s Day series. Earlier in the year, we enjoyed marine biologist Helen Scales’s Shell Day and behavioural ecologist Marty Crump’s Snake Day. Insect Day: A story of 24 hours and 24 hexapod lives follows the same pattern, acting as an hourly guide, this time following insects as they hunt for food, mates or just plain safety from predators. Author Erica McAlister is a curator at London’s Natural History Museum who studies flies. She starts at midnight in Africa with a female mosquito, Anopheles gambiae, which is out for the blood of any unwitting sleeper and may unintentionally transfer malaria. Who knew, by the way, that the males have no taste for blood?

By 7am, we’ve moved on to the Arctic circle, where a queen of Bombus polaris, the Arctic bumblebee, is basking within the flowers of the Arctic poppy. She can also keep warm simply by vibrating. Throughout the day, we meet the yellow-legged saddle casemaker (Agapetus ochripes), the blue-winged helicopter (Megaloprepus caerulatus), the Peruvian shield mantis (Choeradodis rhombicollis), the ferocious water bug (Abedus herberti) and Grote’s bertholdia (Bertholdia trigona). In its closing pages, Insect Day delivers a final punch: we’ve just toured insects, but there may be as many as 30 million more yet to describe.

by Richard Dawkins

A new Richard Dawkins book is always a bit of a treat, and 42 Tales from Life: A modern bestiary looks set to be no exception. This is a collection of animal tales, explaining how they evolved into the extraordinary, intriguing and often beautiful forms they have, with a colourful backdrop of illustrations by 19^th-century naturalist, morphologist and artist Ernst Haeckel. According to the publisher, Dawkins reveals “the fundamental truths behind even the most unfathomable animal behaviours”, such as the galloping of fish, the shape of the rhinoceros’ horn, the surprising similarities between horses and lizards, and why hummingbirds glow so brilliantly. The book starts with “The Cephalopod’s Tale” and “The Hummingbird’s Tale”, ending with “The Bat’s Tale” and “The Frog’s Tale”. They are accompanied by Haeckel’s art, whose depictions of plants, sea creatures and other animals turn out to have fascinated Dawkins all his life.

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There are some stories that stay with you forever, the big scientific moments that change the course of history. These are not those moments – but we can’t stop thinking about them anyway.

Push my button

Surgeon Stuart Meloy was performing a pain-relief operation on a woman’s spine when she started exclaiming emphatically. “You’re going to have to teach my husband to do that,” the woman said. This inspired Meloy to invent an implant to help women who are unable to achieve orgasms in the usual way. New Scientist broke the news in 2001, sparking a frenzy of worldwide media excitement. But 13 years later, Meloy was still struggling to raise funds for a full clinical trial, and the “orgasmatron” never reached a climax.

Monkey pleasure

We aren’t the only primates capable of coming up with creative ways to pleasure ourselves. In a study of long-tailed macaques (Macaca fascicularis) in Bali, Indonesia, at the University of Lethbridge in Alberta, Canada, and her colleagues filmed hundreds of examples of male and female monkeys using stone tools as sex toys, rubbing or tapping them on their genitals. According to at the University of Western Australia, the Balinese monkeys get plenty of food handouts from humans, and this frees up time for sexual experimentation. But some monkeys in other places have unusual kinks, too: another study reported a wild macaque in Japan rubbing its genitals on the back of a sika deer.

Head transplants

In 2015, surgeon Sergio Canavero announced plans to carry out the first human head transplant, intended to extend the lives of people with muscle and nerve degeneration or widespread cancer. He claimed his technique could overcome technical hurdles, including how to fuse the spinal cord and prevent the body’s immune system from rejecting the head. In the following two years, Canavero published animal experiments supposedly backing up his methods, but other surgeons remained highly sceptical. A human head transplant never did happen, but Canavero has reportedly moved on to an even bolder ambition:

Rats driving

Have you ever wondered if a rat can drive a car? Kelly Lambert at the University of Richmond in Virginia has. She and her colleagues built a tiny car with three copper bars that would steer it left, forward or right. Sure enough, 18 rats learned to drive towards food rewards. They even found it relaxing, as measurements of their stress hormones indicated. Lambert proposed that driving challenges could replace traditional maze tests when using rat models to study neuropsychiatric conditions.

The sniff test

Humans are more similar to rats than we like to think. In a psychology experiment, and his colleagues at the Weizmann Institute of Science in Rehovot, Israel, surreptitiously filmed 153 volunteers. After shaking hands with someone of the same sex, people smelled their shaking hand more than twice as much as they did before the handshake. Puzzlingly, after shaking hands with someone of the opposite sex, people were more likely to sniff their non-shaking hand. The team suspected that humans use chemical signals all the time without being aware of it.

Urine fountains

Communication through scent is, of course, widespread in mammals, but some never-before-seen behaviour in dolphins took biologists by surprise in 2025. While studying Amazon river dolphins (Inia geoffrensis), or botos, in Brazil, Claryana Araújo-Wang at CetAsia Research Group in Ontario, Canada, saw a male “flip his belly up out of the water, expose his penis and then proceed to urinate into the air”, she told New Scientist. They saw dolphins do this a total of 36 times, and most of the time another male was nearby and would pursue the stream of urine. The purpose of this behaviour hasn’t yet been established, but hormones in urine might signal a male’s social position or physical condition, said Araújo-Wang.

Giving the finger

As for human modes of communication, many of us struggle to put our smartphones down – so the last thing we’d want is for them to crawl across the table towards us. Nevertheless, Marc Teyssier at the University of Paris-Saclay in France and his colleagues gave phones this ability in 2018, with a robotic appendage dubbed the MobiLimb. It plugs into a device’s USB port and, for some reason, looks eerily like a human finger, giving it a spooky quality reminiscent of Thing from The Addams Family. The MobiLimb can stroke your wrist, wave, wag like a tail or, most disconcertingly, drag the phone around. Thankfully, the idea hasn’t taken off.

Horror frog

If you find the thought of a phone with a finger horrifying, wait until you hear about the nightmare-inducing hairy frog Trichobatrachus robustus. In 2008, researchers reported that these frogs can break their own bones to produce claws that burst through their skin. at Harvard University’s thought these weapons were for defence, but two years later, that they were used in fights between males – and that the frog’s unusual hairs were a kind of armour to protect its vulnerable parts from sharp claws.

Corpse shrinking

In 1957, when New Scientist was 1 year old, we reported on a new method for shrinking an adult human body to the size of a baby. At an exhibition of inventors in Winnipeg, Canada, the unnamed inventor of this process claimed it would make disposing of dead bodies simpler, as they could be slid into underground tubes and take up less space. The method involved applying high pressure to the corpse and squeezing out fluids so its flesh could be compressed into a mould. “All this is, of course, highly ingenious but it is uncertain why the inventor thinks that his newly proposed form of burial is in any way better than the current and very popular method of cremation,” the writer mused.

Transient anus

We may take it for granted, but the anus, which allows food to pass through the body, was an evolutionary breakthrough, both figuratively and literally. The earliest animals, like jellyfish today, had only one gut opening, where food went in and waste came out. In 2019, scientists discovered that the warty comb jelly (Mnemiopsis leidyi, pictured top) forms an anal opening when it needs to defecate, but it vanishes straight afterwards. This, they suggested, could represent how the anus evolved in the first place.

Fart science

Flatus – gas expelled from the anus – has been a topic of endless fascination for many readers (and journalists). In 2001, we featured the work of Michael Levitt at the Veterans Administration Medical Center in Minneapolis, a leading authority on the subject. He developed a “Toot Trapper” that reduces odours by trapping certain gases using activated charcoal. We also reported on a device for monitoring gas emissions from dogs, used to test dog snacks that were supposed to reduce flatulence. In 2016, researchers in Australia worked out which foods cause the smelliest farts by mixing faeces with different foods. They recommended eating less protein and more slow-release carbohydrates to minimise hydrogen sulphide production. In 2022, at the Mayo Clinic in Rochester, Minnesota, and his colleagues worked out that some poos float because of gas from gut microbes, confirming a hypothesis first put forward by Levitt 50 years earlier.

Brew your own

Even stranger things go on inside some people’s intestines, as we found out in 2019. A 46-year-old man started experiencing unexplained mental fogginess, dizziness and memory loss, and had to give up his job. Later, doctors found high levels of alcohol in his blood when he hadn’t been drinking. Eventually, they realised his gut contained high levels of Saccharomyces cerevisiae – brewer’s yeast – which got him drunk any time he ate a lot of carbohydrates. This rare condition, known as auto brewery syndrome, had been triggered when the man took antibiotics for a thumb injury, which disrupted his gut microbiome. This year, a study reported that another man with this condition fully recovered after getting a transplant of faeces from a healthy donor. Both articles were written by Alice Klein, who we also have to thank for the monkey sex toys, car-driving rats, smelly farts and floating poos. Thanks, Alice!

You don’t need a jet plane to get jet lag – even feathers will do. At least one species of bird gets jet lag, in the sense that its body clock can diverge from local time by more than an hour on fast flights across the Atlantic, as revealed by navigational errors.

“We’ve slightly shied away from using the term jet lag itself, because people associate that with the health impacts of that clock shift, rather than the clock shift itself. But it’s exactly the same process that causes jet lag in people,” says at the University of Oxford. “It’s having these physiological and behavioural effects, where the birds are mistiming their behaviours.”

It is likely that other long-distance fliers, possibly including some insects and bats as well as birds, also get jet lag in the clock-shift sense, says Lewin.

Manx shearwaters are small seabirds that fly vast distances, using a technique called to exploit wind gradients near the sea surface. “They’ve evolved this niche of being really amazing long-distance travellers,” says Lewin.

They breed on islands around the UK and Ireland. While parents are raising a chick, they may fly more than 1000 kilometres westwards to reach rich fishing grounds in the mid-Atlantic. Once they have food, they fly back in a fairly straight line, diverting only to skirt around landmasses such as Ireland.

How do they achieve these navigational feats? While some birds can sense Earth’s magnetic field, Manx shearwaters don’t appear to. Lewin’s team has confirmed this by attaching small magnets to the birds that should disrupt geomagnetic navigation. They .

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Instead, it appears that shearwaters rely on a sun compass – if you know what time it is, you can maintain a course by adjusting your orientation relative to the sun. Many animals, from insects and fish to turtles and birds, have been shown to do this. If their internal clocks are reset using artificial light and darkness, they head in the wrong direction.

“We realised that there might be a kind of natural experiment where the birds were manipulating their own clocks,” says Lewin.

For instance, at 6am, a Manx shearwater wanting to fly eastwards back to its nest needs to head sunwards. At noon, it needs to fly at right angles to the sun, which will be due south. But if a shearwater travels 15° of longitude eastwards, the local time will be 1pm, while its internal clock will still register the time as noon, so the sun will no longer be due south. This means birds flying rapidly east should veer slightly off course in a clockwise direction over the course of day, in the absence of other cues.

Other researchers have been attaching GPS trackers to Manx shearwaters for decades, so the paths taken on nearly 4000 foraging trips are known. Sure enough, when Lewin and his colleagues analysed these flight tracks, they found birds on rapid return flights tended to deviate clockwise when out of sight of land.

The team considered other potential explanations, from the Coriolis effect to winds. “The one thing that best predicted the observed changes in shearwaters’ orientation was always this sun compass effect,” says Lewin.

The effect is small. After a 1000 km flight, a bird would have to fly only an extra 5 km to reach its colony, which, for such efficient long-distance fliers, is probably negligible, Lewin says. This might explain why Manx shearwaters haven’t evolved some mechanism for avoiding jet lag, he says.

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“What is good about the study is that they analyse a lot of tracks, making for robust data to test different models,” says at Macquarie University in Sydney.

While other species may get this form of jet lag, too, long-distance flights by birds are typically done during migrations, and migrations usually involve mainly north-south travel, says Cheng, so jet lag won’t be much of a problem.

However, near the poles, the travel distance required to cross 15° or more of longitude becomes so short that many animals might be affected, says Lewin, perhaps even including polar bears or Arctic foxes travelling on sea ice.

“Near-polar species may be quite strongly affected,” he says. “Now, it all gets a bit complicated because you have 24-hour daylight and 24-hour darkness in parts of the year, so circadian rhythms break down generally in some species.”

Wind turbines have killed nearly 19 million bats in the US over the past four decades, according to the most comprehensive analysis of its kind to date. The problem seems to have worsened in recent years, with more than 1.5 million deaths now occurring annually.

But there may be ways to make this green energy source safer for wildlife without overly affecting energy production. This data can help “advance research to really support effective conservation measures and science-driven decision-making in the future”, says at Fort Collins Science Center in Colorado.

Bats play a vital role in ecosystems, particularly by controlling insects like mosquitoes and moths that produce crop-killing caterpillars. But many species face growing threats from habitat loss, disease and human activities, with some now classified as threatened or endangered.

These human-activity threats include use and the building of . Researchers have also previously found during required monitoring to comply with wildlife protection regulations. But not all wind farms share their results, and monitoring methods vary from site to site, says team member , also at Fort Collins Science Center.

“We know bats are being impacted, but could we change the engineering or sites of a turbine to minimise those impacts?” she asks. “There’s been an increasing interest in this, but we just haven’t had the appropriate data yet.”

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Now, Straw, Labuzzetta and their colleagues have analysed 499 reports from wind farms across the 48 adjoining US states to estimate how many bats were killed by turbines from 1981 to 2024, focusing on 10 species. They used a statistical model that considered differences in how wind farms searched for dead bats, the size and design of their turbines, and the surrounding environment.

Their results suggest that wind turbines killed an estimated 18.7 million bats between 1981 and 2024. Annual deaths seem to have exceeded 1.5 million from 2021 onwards, which may be the result of more wind turbines being installed.

Hoary bats (Lasiurus cinereus) had the greatest losses, with an estimated 6.7 million deaths, followed by 5.8 million deaths among eastern red bats (Lasiurus borealis), 3.4 million among silver-haired bats (Lasionycteris noctivagans) and 1.5 million among big brown bats (Eptesicus fuscus).

Wind farms near rivers and turbines with longer blades were linked to more deaths among certain species, while having more space between the blades and the ground may reduce the risk.

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The researchers aren’t sure why bats fly so close to wind turbines. suggests that migratory bats mistake the structures for trees and approach them in search of food, shelter or mates. A recent European study also found that , potentially attracting females into the path of spinning blades. Differences in species prevalence and behaviours may partly explain why some seem to be more at risk than others.

The researchers hope their findings will help wind farm developers protect bats by choosing safer locations and adjusting turbine designs. For example, research suggests that stripy wind turbines could prevent seabird collisions.

Changing when turbines operate might also help. shows that temporarily shutting them down during periods of high bat activity, particularly in low winds, can substantially reduce fatalities with limited loss of electricity production.

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.