Philippa Kaur

Sputnik/Science Photo Library
THE human story only becomes more intricate and fascinating. For hundreds of thousands of years, a mysterious group known as the Denisovans lived in the east of Asia – even as our species was emerging in Africa and beginning to spread around the world. Their homeland spanned thousands of kilometres and they existed as a group longer than we have as a species. Yet they were utterly unknown until 2010, when they were identified from DNA preserved in a bone fragment.
A decade later, the Denisovans remain enigmatic. We know they were a sister group to the Neanderthals, … More

By Ibrahim Sawal
Hand gestures affect the way people hear you
Getty Images/Westend61

Making simple up and down hand movements while speaking may influence the way people hear what you are saying.
We often use meaningless movements, such as flicking or waving our hands, known as beat gestures when speaking face to face. These typically align with prominent words in speech.
“Politicians use these gestures all the time to get their message across,” says Hans Rutger Bosker at the Max Planck Institute for Psycholinguistics in Nijmegen, the Netherlands.

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Bosker and his colleagues tested how important these movements are in influencing sound recognition. They presented Dutch participants with videos of Bosker saying Dutch words that have two meanings depending on which syllables are stressed – an example in English would be the difference between object and object. Bosker paired each word with a beat gesture either on the first syllable or the second syllable.
The team found that participants were on average 20 per cent more likely to hear stress on a syllable if there was a beat gesture on it. Mismatched beat gestures also biased what they heard, with 40 per cent of participants hearing the wrong sound.

“The timing of even the simplest hand movement is vital to face-to-face communication,” says Bosker. “We’ve shown how multimodal speech perception really is,” he says.
This could be a learned association, but there could be an evolutionary reason behind it says Wim Pouw at Radboud University in Nijmegen, who wasn’t involved in the research. “Manual gestures, like those with a beat quality, interact with the vocal system by using muscles that can increase lung pressure. This affects vocal qualities associated with stressed speech,” says Pouw. He suggests that observing these gestures helps us to perceive these changes in vocal qualities.
Although only tested in Dutch, Bosker says similar effects may be seen in other similar languages such as English, and may even be present in all languages. “This effect could be generalised to much more than just Dutch, but this is highly speculative,” he says.

Bosker says that his research is even more important during the current coronavirus pandemic. “With people wearing face masks, we can’t lip read. Our data explains how much communication can be improved if we gesture along,” he says.
Journal reference: Proceedings of the Royal Society B, DOI: 10.1098/rspb.2020.2419
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The existence of the Denisovans was discovered just a decade ago through DNA alone. Now we’re starting to uncover fossils and artefacts revealing what these early humans were like

Humans 27 January 2021
By Michael Marshall

Brian Stauffer

TODAY, there is only one species of human alive on the planet. But it wasn’t always so. For millions of years, and until surprisingly recently, there were many types of human-like groups, or “hominins”. They coexisted, perhaps they fought, and they interbred. It would be fascinating to know how these others lived, but understanding who they were and what they were like is extremely challenging. We cannot put ourselves into their minds, and we have only fragmentary clues from fossils and artefacts they left behind to reconstruct their lives.
That challenge is especially daunting for one of these extinct groups, the Denisovans. Discovered just a decade ago, the Denisovans have left us scant physical evidence. Instead, our knowledge of them comes almost entirely from their preserved DNA. It tells us that they are a sister group to the Neanderthals, that they lived in Asia for hundreds of thousands of years and that they interbred with our species. But we don’t know what they looked like, how they walked or if they could speak.
Now, that is changing. In the past few years, archaeologists have alighted on a few fossils that seem to be Denisovan. They have also unearthed treasure troves of artefacts, including tools, jewellery and even art, that they think were created by these mysterious people. These interpretations are potentially explosive, so it is hardly surprising that some dispute them. Nevertheless, we are starting to piece together a picture of the Denisovans, one of our closest cousins, and a group that still lives on in the DNA of many people today.
The discovery of the Denisovans … More

By Christa Lesté-Lasserre
Extroverts seem to find it easier than introverts to improve their dog’s behaviour
Kevin Kozicki/Image Source/Getty Images

Dogs with certain kinds of behavioural problems are more likely to show improvement during training if their owners are extroverts and open-minded.
After comparing human personalities and the success of behavioural training, scientists have found that introversion, close-mindedness and even conscientiousness are linked to fewer changes in some types of undesirable dog behaviour, including aggression and fearfulness.
The information could help veterinarians identify dog-owner pairs that might need more help during training, says Lauren Powell at the University of Pennsylvania School of Veterinary Medicine, who co-led the study.

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Over a six-month period, Powell and her colleagues followed 131 dogs and their owners attending training sessions with a University of Pennsylvania veterinarian, who performed an initial behaviour assessment of each dog. The dogs had various issues, such as aggression towards people or dogs, chasing cars or animals, general fearfulness, separation anxiety, excessive barking and fear of being touched.

Owners underwent personality testing and provided information about their dogs through a global canine research database called C-BARQ. The researchers also used a survey to evaluate how attached each dog and owner were to one another.
The most important factor affecting success was how bad the dog’s behaviour was to start with, Powell says. Those with the worst behaviour improved the most over six months – possibly because they had so much to gain from the training.
Confirming previous studies, the group also noted that younger dogs improved more than older dogs, and that the stronger the pair’s attachment, the more successful the training was.
However, their research also revealed that human personality plays a role in corrective training for some kinds of unwanted behaviour.

For example, dogs that were generally fearful or afraid of being touched made more progress during therapy if their owners were extroverted. And people who were open to new experiences tended to have dogs that became gradually less fearful towards other dogs – perhaps because these owners were more willing to adopt the vet’s recommendations, says Powell.

The findings make sense, says Charlotte Duranton, head of Ethodog, a canine behavioural research facility and clinic near Paris, since dogs and their owners tend to “synchronise” their behaviour with each other, especially in social settings.
“When dogs are confronted with a new stimulus – like an unfamiliar human, dog, or object – they’re going to watch the reaction of their owner to know how they themselves should behave,” says Duranton. As such, it is critical for professionals to keep this in mind during behaviour training. “The dog isn’t the only [partner] to consider,” she says.
As for the more conscientious people, Powell says her data showed that their dogs did not become particularly less aggressive towards strangers despite six months of retraining. But these results might be somewhat affected by the fact that the owners themselves were reporting on their dogs’ behaviour. “More conscientious people may just view their dogs’ behaviour differently than less conscientious people do,” she says.
Journal reference: Frontiers in Veterinary Science, DOI: 10.3389/fvets.2020.630931
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The late Mike deGruy filmed iconic underwater footage that wowed audiences, drawing the admiration of David Attenborough and James Cameron. A fond documentary by his wife reveals the real man

Life 20 January 2021
By Elle Hunt
DeGruy exploring more than 117 metres below the surface in a diving suit
Adventure Entertainment

Diving Deep: The life and times of Mike deGruy
Mimi Armstrong deGruy
Streaming on Apple and Amazon Prime from 19 January

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IT SPEAKS volumes about the kind of person Mike deGruy was that, after he nearly lost his life in a shark attack, he not only continued diving, he returned to the scene to figure out where he had gone wrong.
The film-maker and biologist is the subject of Diving Deep, a documentary directed by his widow, fellow film-maker Mimi Armstrong deGruy, in the wake of his death. Mike DeGruy was killed in a helicopter crash – along with Australian film-maker Andrew Wight – while on assignment in Australia in 2012.
The film takes a fond look at his adventurous and compassionate life, leaving no doubt that he lived it to the fullest and what he would want his legacy to be.
In 30 years of marine film-making, deGruy gained a reputation for both his stubborn pursuit of the shot, often in unprecedented conditions, and his passion: he was remembered at his funeral as a “human exclamation mark”.
In 1986, deGruy filmed a volcano eruption in Hawaii as experienced underwater, pushing his bodyboard straight into the oncoming lava. Later, he put himself in the path of hunting orcas, capturing the first film of them seizing sea lion pups from the water’s edge – footage that is now iconic in nature film-making.

David Attenborough – who voiced deGruy’s footage for many years, including on the Emmy and Bafta-winning The Blue Planet – recalls it causing “a sensation” at the BBC: “Everybody was talking about it… Those pioneering sequences hold their place in the history of discovery.”
Between archival footage and fond recollections from family and collaborators, deGruy is an engaging person to get to know. His life’s story is one that might inspire you to make more of yours, if only through the sheer force of his enthusiasm.
DeGruy was a risk-taker, but an informed one. His fearlessness in the face of sharks was rooted in an understanding of them and their behaviour, so when one took off part of his right arm while he was filming in the Marshall Islands in 1978, requiring 11 operations, deGruy’s response was to make a film exploring why.
“When a shark took off part of his arm while shooting, deGruy’s response was to make a film exploring why”
He later campaigned, as a shark-attack survivor, for shark conservation and used his clout as a fixture on cult TV show Shark Week to push back against sensationalist treatment of them. This led him to be identified on television news as a victim of “Sharkholm syndrome”.
But it wasn’t until the 2010 Deepwater Horizon oil spill in the Gulf of Mexico, where deGruy had grown up learning to freedive, that he really embraced activism. The devastation he documented at the scene, and the reluctance from many quarters to accept responsibility for it, drew out a new and urgent purpose to his film-making.
Footage of deGruy rallying against the disparity between polluters’ profits and funding for science was what prompted his widow to put together Diving Deep.
Today, more than a decade later, the full impact of Deepwater Horizon is still unclear because so much of the ocean is undocumented, especially at depth. “We were in some ways working in the dark,” says Charles Fisher, a marine biologist at Pennsylvania State University.
As the technology evolved to take him to greater and greater depths, DeGruy was drawn to uncover the mysteries of the deep and what lessons they might hold for humanity. He had been due to join James Cameron’s Deepsea Challenge, venturing into the Mariana Trench, when he died.
Paying tribute to deGruy in the film, Cameron offers a theory for the lack of impetus and investment in deep-sea exploration compared with that for outer space. The space race, he says, represents man’s desire to conquer his environment, but you don’t conquer the ocean, he says. “You understand the ocean, you become intimate with the ocean, you let it teach you.”
DeGruy’s life stands as a testament to the possibilities of that approach. It is demonstrated in the film’s opening sequence as he ventures more than 117 metres deep in a diving suit, an underwater astronaut wearing a blissful smile, a man completely immersed.
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From Now, created by Rhys Wakefield and William Day Frank, is podcast company QCode’s drama about brothers reunited across space and time. Brian Cox and Richard Madden play identical twins, set at loggerheads by relativity.

Stuart Clarke

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Climate Change: Why should we care? features mathematician Hannah Fry and luminaries including conservationist Jane Goodall (pictured), at London’s Science Museum on 28 January. Join in online to discover the difference that climate efforts make.

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Small Gases, Big Effect: This is climate change by David Nelles and Christian Serrer explains climate change with the help of more than 100 scientists, presenting complex science in a way that everyone will find easy to understand.
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Lack of diversity in genome studies means that treatments derived from them are leaving people of colour behind. Changing that isn’t only about justice – it could also lead to new therapies that would otherwise go undiscovered

Health 20 January 2021
By Layal Liverpool

Ruby Fressen

IF YOUR doctor suspects you might have type 2 diabetes, they will want to know your average blood sugar level, which typically means taking a glycated haemoglobin test. This method of diagnosis is recommended by the World Health Organization and used pretty much everywhere. The problem, as Deepti Gurdasani discovered in 2019, is that the test may not work for everyone.
Gurdasani and her colleagues found that a gene variant present in almost a quarter of people with sub-Saharan African ancestry alters the levels of glycated haemoglobin in their blood independent of blood sugar. This suggests they will be more likely to be falsely diagnosed with diabetes, she says.
Gurdasani’s discovery is just the latest in a growing list of medical injustices resulting from the fact that the vast majority of people who have had their DNA sequenced are of European descent. Again and again, people from under-represented backgrounds find that drugs and diagnostics based on research that makes connections between DNA and disease don’t work for them. The dearth of diversity in these studies also means that people in overlooked populations are more likely to get inaccurate results from tests that look at an individual’s genetic risk of developing a condition, excluding them from the much-vaunted promise of personalised medicine.
All of which explains why researchers like Gurdasani, a geneticist at Queen Mary, University of London, are sequencing the DNA of thousands of people from under-represented populations around the world. This isn’t just about justice: increasing the diversity of genetic studies could also uncover novel genetic variants associated with disease, providing targets for treatments that … More