Category: The Conversation – UK

Source: The Conversation – UK – By Tom Brownlee, Associate Professor, Sport and Exercise Science, University of Birmingham

Imagine if your smartwatch didn’t just tell you how many steps you’ve walked or calories you’ve burned, but how many heartbeats you’ve “spent” each day. According to a recent study, that number might one day become another marker of health – a “heartbeat budget” that could, in theory, tell you if you’re overspending your most vital resource.

The idea of a lifetime heartbeat limit has floated around for decades. It’s based on an old myth that the heart comes with a fixed number of beats, often said to be about 2.5 billion, so every extra one you use brings you closer to running out. Thankfully, that’s pretty roundly accepted now to be untrue.

Exercise doesn’t shorten your life by making your heart beat faster. If anything, people who exercise tend to have lower resting heart rates and live longer. But the new research, published in JACC: Advances, borrows that same metaphor in a modern, data-driven way.

The scientists behind the study analysed fitness-app data from elite athletes, comparing resting heart rates with total daily beats. They estimated that endurance-trained athletes “save” around 11,500 heartbeats per day compared with untrained adults, thanks to lower resting rates.

But those savings don’t last. A single Tour de France stage can cost riders about 35,000 extra beats – according to the researchers’ estimates – reflecting just how hard the heart works during a competition.

This push and pull, saving beats at rest, spending them during exertion, is what researchers call heartbeat consumption. The concept is simple: your total beats per day reflect how your heart responds to everything you do, from sleep to stress to sport. Fitness trackers already measure heart rate continuously, so it wouldn’t take much to start summing those beats and turning them into a new health metric.

But does it actually mean anything? That’s where things get murkier. The study’s authors admit their analysis was small and observational. They didn’t track participants’ health outcomes, only patterns in their heart rate data. A high daily heartbeat count could mean someone is active, or it could reflect anxiety, poor fitness, caffeine or heat. Without context, the number itself tells us little.

Still, the idea has intuitive appeal. Heart rate is one of the clearest windows into how our body is coping with life’s demands. A persistently high resting heart rate has been linked to an increased risk of heart disease, stroke and early death.

Meanwhile, variability in the timing between beats, known as heart rate variability, is a well-established indicator of stress and emotional wellbeing. Thinking in terms of “beat consumption” could help people visualise that connection between physical and mental load.

Athletes already know the power of that balance. Training too hard, too often, can elevate resting heart rate, reduce heart rate variability and blunt performance – a classic sign of overtraining.

Lighter, so-called active recovery sessions, where the heart rate stays low, are known to speed recovery, improve overall performance and stabilise mood. If a “heartbeat budget” helps people notice when their ticker is working overtime, it might encourage gentler activity days before burnout hits.

What the data doen’t tell us

There are also implications for people living with chronic conditions. Some health apps already use heart rate thresholds to help users avoid overexertion, especially when fatigue or heart strain can make recovery costly. In that sense, tracking heartbeat consumption could serve as a safety signal rather than a competition, a way of knowing when the body needs to slow down.

But as with most bright new ideas in fitness science, a note of caution is needed. The JACC authors acknowledge that they used fitness tracker data from a small sample of highly trained cyclists and runners. That’s a narrow slice of the population.

They didn’t measure blood pressure, oxygen levels or recovery biomarkers – all of which matter for heart health. Translating those findings into advice for ordinary smartwatch users will take larger, long-term studies.

Then there’s the philosophical question: should we really treat heartbeats as a finite commodity? Exercise “spends” heartbeats in the short term but often “earns” more life in the long run.

A long-distance runner’s heart might beat more times in a single day, but fewer times across a lifetime, because endurance training lowers resting rate and improves cardiac efficiency. In that sense, using your heart isn’t the problem, but not using it might be.

Heartbeat consumption, at least for now, remains a metaphor in search of meaning. Still, it’s a poetic one. Whether or not your fitness tracker or smartwatch ever starts counting total beats, the message behind it is simple: pay attention to how your heart behaves across the day. It’s not about saving beats – it’s about spending them wisely.

Tom Brownlee does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Should you be concerned about ‘overspending’ your daily heart beats? – https://theconversation.com/should-you-be-concerned-about-overspending-your-daily-heart-beats-266829

Source: The Conversation – UK – By Rob Salguero-Gomez, Professor of Ecology, University of Oxford

I’ve long been fascinated by one of the most stubborn patterns in biology: males and females rarely live the same length of time. In humans, women nearly always outlive men, with an average advantage of about five years worldwide today. This pattern holds across history, from 18th-century Swedes to contemporary Japanese – though the magnitude of this sex-difference can vary considerably.

Humans are not alone in showing such sex biases in longevity. Across the Tree of Life, sex differences in longevity are widespread, but they are neither uniform nor always female-biased.

And a new study study led by evolution researcher Johanna Staerk, published in Science Advances, conducted the most comprehensive analysis of sex differences in longevity in birds and mammals. The study offered new insight into why these differences evolved and found these differences are more pronounced in the wild than in zoos.

Among mammals, females generally live longer. The recent comparative study examined 528 mammal species in zoos and found that 72% showed a female life expectancy advantage, averaging 12% longer lives for females. In the wild, where environmental pressures are stronger, the female advantage was even greater: around 19%.

In my own work with the Compadre animal demographic database and with wild populations, I’ve seen the same female advantage emerge time and again. Wild female African elephants often live into their 60s, while males rarely exceed their late 40s. This is in part because males spend much of adulthood in risky solitary ranging and competing through combat. Similarly, in moose, females live twice as long (17-22 years) as males.

Genetics plays a key role. Male mammals are the heterogametic sex (meaning males have an X and a Y sex chromosome), so males are more likely to inherit recessive x mutations. Also high levels of testosterone can suppress immune function.

However, the clearest evidence points to sexual selection. In polygynous mammals (males compete for access to harems of females) such as red deer or lions, males grow large bodies and weaponry, and fight for mates, which reduces their survival chances.

Birds: the male advantage

The reversal in birds still surprises students when I teach life-history theory. Biology rarely hands us neat rules.

Across the 648 avian species studied in zoos by Staerk and colleagues, in 68% of them males outlived females, with an average 5% male advantage. In the wild, the gap widened to over 25%.

Female birds are the heterogametic sex (ZW chromosomes), which may expose them to greater genetic risks. More importantly, many female birds pay heavy reproductive costs. Egg production, incubation and chick rearing demand enormous energy. In some species such as ducks and songbirds, this burden translates into shorter female lifespans.

The exceptions are illuminating. Raptors like buzzards and eagles often show a female advantage. In the wild, female tawny owls live longer. But in zoos the advantage shifts to males. The reason is not yet known.

Beyond fur and feathers

Previous research has shown insects have vivid contrasts in longevity. In many moths and mayflies, females live only a few hours or days as adults, exhausting themselves in egg laying, while males persist days or weeks longer. Insects who live in highly organised colonies reverse this pattern: ant and bee queens can live decades, far outlasting short-lived male drones.

Here, the colony shields queens from many ecological risks, such as the need to evade predators when out looking for food, illustrating how social organisation can radically alter the relationship between sex and survival.

Amphibians and reptiles are known to showcase mixed patterns. Male frogs often die younger due to the costs of calling and combat at breeding sites, whereas female frogs sometimes pay higher survival costs through egg production.

Fish often show flexibility in sex roles, alongside variability in female and male lifespans. In stickleback fish, males provide sole parental care, defending nests at great cost. They often die shortly after the breeding season, while females survive to reproduce again. Conversely, in species where females produce enormous clutches, their shorter lives balance the equation.

Humans in context

Across cultures and history, women live longer than men. In 21st-century Japan, female life expectancy exceeds 87 years, compared to 81 for men. Among Hadza hunter–gatherers, who live in Tanzania, women live longer than men too.

Social and medical advances, such as better maternal care, have widened the human female edge in modern populations.

Intriguingly, the human “female advantage” is smaller than in apes, probably because sexual selection is weaker in humans. Female chimpanzees and gorillas live substantially longer than males, often by more than a decade. Indeed, men face fewer risks from mate competition than chimpanzees.

Why does sex-based longevity differ so much?

There are two main hypotheses. First is the heterogametic sex hypothesis, as mentioned above, which predicts that the sex with two different sex chromosomes (XY in mammals, ZW in birds) suffers shorter lives. However, this fails to explain the exceptions, such as long-lived female raptors.

Second are life history and sexual selection trade-offs. Traits that increase reproductive success often reduce survival. Among mammals, males die younger when they invest heavily in competition, size or weaponry. Among birds, females pay with their lives for egg production and parental care. The new study supported this explanation. Non-monogamous mammals with significantly larger males show the largest female advantage.

Who wants to live forever anyway

A longer life does not necessarily translate into better quality of life. In humans, although women live longer almost everywhere, they often spend more years in poor health compared to men, burdened by chronic conditions such as osteoporosis, dementia or autoimmune disorders. Similarly, in some nonhuman animals, females survive longer but may experience prolonged periods of reduced reproduction or physical performance.

A “female advantage” in survival may therefore come with hidden costs.

So, do females live longer than males across the Tree of Life? Often, yes, but not because of a universal law. The patterns are the messy product of chromosomes, hormones, competition, care and chance. That’s what makes it such an interesting question to study.

Rob Salguero-Gomez receives funding from NERC.

– ref. Why do so many female animals live longer than males? New research – https://theconversation.com/why-do-so-many-female-animals-live-longer-than-males-new-research-266824

Source: The Conversation – UK – By Daniel Joinson, PhD Candidate, Engineering and Maths, University of Bristol

What if the problem with social media isn’t just how much we use it, but when? A new study suggests that scrolling and posting through the small hours may be a red flag for mental wellbeing – and the effects could be as significant as binge drinking.

For the study, published in Scientific Reports, my colleagues and I analysed the Twitter (now X) habits of 310 adults and discovered that those who regularly posted between 11pm and 5am showed meaningfully worse mental wellbeing than daytime users. This finding challenges the current policy obsession with screen time limits and points toward a more nuanced understanding of how social media affects our mental health.

Australia has passed a law to ban social media for anyone under 16, with 68% of the population supporting the new law. Similar proposals are being debated across the western world, where policymakers cite rising concern about youth mental health. But is the solution that simple? Science tells a more complicated tale.

Studies examining social media use have found associations with worse mental health, better mental health and even no change at all. And a large analysis of over 350,000 people found that while more time on social media was associated with poorer mental health, the effect was minuscule.

The trouble with this research is its fixation on amounts of time spent on social media. Two people might spend identical amounts of time on social media yet have completely different experiences – one scrolling passively, the other engaged in fraught late-night exchanges. The difference in behaviour matters, and so does the platform where it occurs.

Complete bans will eliminate harmful effects, but they also remove potential benefits. Many young people rely on these platforms to form and maintain friendships. For those already struggling mentally, social media can provide support, guidance and community that might otherwise remain out of reach.

On the other hand, late-night use could push back bedtimes, fracture sleep quality and consequently harm mental health. The harm may intensify with highly interactive activities – posting, messaging – compared with passive browsing.

Understanding what people do on social media – and crucially, when they do it – is essential to grasping its real effect.

The night shift: what we found

Our study explored this using real-world Twitter data from participants in the Avon Longitudinal Study of Parents and Children, matched with detailed self-reported mental health measures. These include the Warwick-Edinburgh Mental Wellbeing Scale – a 14-item measure of how someone feels and functions. We produced statistical models, aiming to predict these measures of mental health from the average time of day our participants posted their tweets.

We found strong evidence that the time someone posts on Twitter was associated with their mental wellbeing. Posting time accounted for about 2% of the differences in wellbeing between participants. This may sound small, but it’s a similar effect size to that found for binge drinking in other research.

Regular nighttime tweeters (23:00 to 05:00) consistently reported worse mental wellbeing than those posting primarily during daylight hours.

We also looked at how posting times related to symptoms of depression and anxiety. While mental wellbeing captures the positive side of mental health, depression and anxiety reflect specific problems that can undermine it.

The links between posting time and these symptoms were weaker overall, but they varied by age and sex. For example, the relationship between posting time and anxiety was about twice as strong in older participants, with posting time explaining 1.3% of the differences in anxiety levels among older users compared with 0.6% among younger ones.

Critical questions remain. Are we witnessing the harmful consequences of late-night posting, or do people with worse mental health gravitate toward nighttime social media use? Do these patterns translate to other platforms or different demographics, particularly adolescents and children?

If nighttime social media use genuinely harms mental health, then targeted solutions could be valuable. TikTok recently launched “wind down”, which replaces the homepage for under-16s with calming music and breathing exercises after 10pm. And in the UK, the government is now considering legislation to restrict multiple platforms after 10pm for this age group.

Nighttime use demonstrates how policy and platforms can address potentially harmful behaviour without resorting to outright bans. It represents a shift away from crude measurements of screen time toward considering what people do, when and where they do it, and who they are.

This approach moves us beyond simple measurements, toward a better understanding of how our digital lives affect our mental health.

Daniel Joinson receives funding from the EPSRC (grant number EP/S023704/1)

– ref. It’s not screen time that matters, it’s what you do and when you do it – new study – https://theconversation.com/its-not-screen-time-that-matters-its-what-you-do-and-when-you-do-it-new-study-266845

Source: The Conversation – UK – By William Crozier, Duns Scotus Assistant Professor of Franciscan Studies, Durham University

Bruised by recent events, the Church of England has just entered a new era. Dame Sarah Mullally’s appointment as the first female archbishop of Canterbury is momentous. But Mullally has an enormous challenge ahead of her in healing the wounds that afflict her church. Restoring trust in the church’s senior leadership and preventing the church from fracturing over issues of sexuality and gender will be at the top of her agenda.

Mullally’s appointment comes on the heels of a period of crisis in the church. The former archbishop of Canterbury, Justin Welby, was forced to resign following revelations about how he and other senior church leaders handled historic cases of child abuse.

Mullally made clear that her first task will be to restore confidence in the church’s senior management and safeguarding processes: “As archbishop, my commitment will be to ensure that we continue to listen to survivors, care for the vulnerable, and foster a culture of safety and wellbeing for all.”

As the first female archbishop of Canterbury, Mullally faces a unique set of challenges. A former chief nursing officer for England, Mullally was one of the first women to be made a senior bishop in a diocese when she was made bishop of London in 2018. While many in the Church of England have welcomed women priests and bishops, some – particularly on the traditionalist Evangelical and Catholic wings of the church – continue to oppose women’s ordination.

Mullally’s role in guiding the global Anglican family is also complicated by the fact that many of its member churches do not accept women bishops and priests. Senior Anglican leaders from Africa and Asia have openly criticised her appointment, both because she is a woman and because of her views on same-sex marriage.

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Read more:
First woman archbishop of Canterbury can’t preside over communion in hundreds of churches

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Mullally will have to try and build bridges with those who oppose women priests and bishops – and who thereby deny her right to hold the office of archbishop – while assuring them that the church can still provide suitable provisions for them.

Leadership culture

Along with restoring trust in the church’s safeguarding processes, Mullally must also heal divisions within the church’s hierarchy over leadership culture. In the weeks leading up to Welby’s resignation, both he and the archbishop of York, Stephen Cottrell, were accused of using “coercive language” by the bishop of Newcastle, Helen-Ann Hartley.

According to Hartley, both archbishops showed a “complete lack of awareness of how power dynamics operate in the life of the church”. Mullally is now in a position to encourage reconciliation within the church’s hierarchy, and to lead it in a way that fosters mutual respect and accountability.

Mullally must also encourage more people to join the priesthood, especially among the under-40s. Key here will be attracting new vocations not only to the parish system, but to “non-stipendary” forms of ministry – priests who hold down regular secular jobs while helping out in local churches. Mullally may have a unique advantage in this respect, given that she was a non-stipendary priest prior to resigning her post as chief nursing officer.

While overall church attendance has declined in recent decades, the trend has reversed slightly in the last few years. In 2024, some 582,000 people regularly attended Sunday services, up from 574,000 in 2023. Mullally’s task will be to help foster this growth, while finding new ways of communicating to a radically changing society.

Same-sex marriage

Currently, the Church of England does not conduct same-sex marriages, nor does it allow its clergy to enter them. In 2017, however, it launched Living in Love and Faith – a project to “listen, learn and respond to changing views” on gender, marriage, relationships and sexual identity.

In light of this, the House of Bishops – one of the church’s main systems of government – voted in 2023 to allow the clergy to offer prayers of blessing for same-sex couples. Mullally was one of the bishops who voted for this move.

Many in the church, including several bishops, are pushing for the church to go further and conduct same-sex marriages. A poll of clergy taken in 2023 by the Times revealed that 49.2% of Church of England clergy would be willing to conduct same-sex weddings. Others, though, oppose any change to the current doctrine, arguing that such a move would contradict both the Bible and tradition.

As archbishop, how Mullally steers the church on this issue will be one of the defining characteristics of her tenure. But she herself cannot change church doctrine. Only the General Synod – the church’s chief governing body – has the power to do this.

Adding an extra degree of complexity is that, as the new archbishop of Canterbury, Mullally is also the spiritual leader of the 85 million-strong global Anglican communion.

Present in 165 countries, the Anglican communion consists of 42 member churches. Some of these, including the Scottish and Canadian Episcopal Churches, already permit same-sex marriage. Others, however, oppose it. Laurent Mbanda, the archbishop of Rwanda, said Mullally had “repeatedly promoted unbiblical and revisionist teachings regarding marriage and sexual morality”.

Should the Church of England – as the “mother church” of the Anglican communion –move towards same-sex marriage during Mullally’s time in office, it is possible that the already deeply divided Anglican communion could fracture irrevocably.

William Crozier does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. The new archbishop of Canterbury has already made history – but she has huge challenges ahead – https://theconversation.com/the-new-archbishop-of-canterbury-has-already-made-history-but-she-has-huge-challenges-ahead-266821

Source: The Conversation – UK – By Clodagh Toomey, Physiotherapist and Associate Professor, School of Allied Health, University of Limerick

Stiff knees, aching hips and the slow grind of chronic joint pain are often accepted as an unavoidable part of getting older. But while osteoarthritis is the world’s most common joint disease, experts say the way we treat and prevent it is badly out of step with the evidence.

The best medicine isn’t found in a pill bottle or an operating theatre – it’s movement. Yet across countries and health systems, too few patients are being guided toward the one therapy proven to protect their joints and ease their pain: exercise.

Exercise is one of the most effective treatments for chronic, disabling joint conditions such as osteoarthritis. Yet very few patients actually receive it.

Research across health systems in Ireland, the UK, Norway and the United States shows the same pattern: fewer than half of people with osteoarthritis are referred to exercise or physiotherapy by their primary care provider. More than 60% are given treatments that guidelines do not recommend, and around 40% are sent to a surgeon before non-surgical options have even been tried.

To understand why those figures are so troubling, it helps to understand what exercise does for joints. Osteoarthritis is by far the most common form of arthritis, already affecting more than 595 million people worldwide.

According to a global study in The Lancet, that number could approach one billion by 2050. Longer life expectancy, increasingly sedentary lifestyles and rising numbers of overweight or obese people are driving the trend.

Yet people who exercise regularly are physically and biologically protecting themselves from developing the disease and from suffering its worst effects.

The cartilage that covers the ends of our bones is a tough, protective layer with no blood supply of its own. It relies on movement.

Like a sponge, cartilage is compressed when we walk or load a joint, squeezing fluid out and then drawing fresh nutrients back in. Each step allows nutrients and natural lubricants to circulate and maintain joint health.

That is why the old idea of osteoarthritis as simple “wear and tear” is misleading. Joints are not car tyres that inevitably grind down.

Osteoarthritis is better understood as a long process of wear and repair in which regular movement and exercise are critical to healing and to the health of the entire joint.

A disease of the whole joint

We now know osteoarthritis is a whole-joint disease. It affects the joint fluid, the underlying bone, the ligaments, the surrounding muscles and even the nerves that support movement.

Therapeutic exercise targets all these elements. Muscle weakness, for instance, is one of the earliest signs of osteoarthritis and can be improved with resistance training. There is strong evidence that muscle weakness increases the risk of both developing the disease and seeing it progress.

Nerve and muscle control can also be trained through neuromuscular exercise programmes such as GLA:D® (Good Life with osteoArthritis: Denmark) for hip and knee osteoarthritis. Usually delivered in supervised group sessions by physiotherapists, these programmes focus on movement quality, balance and strength to improve joint stability and rebuild confidence.

Significant improvements in pain, joint function and quality of life have been recorded for up to 12 months after completing the programme.

Exercise is good medicine for the whole body: it has documented benefits across more than 26 chronic diseases. In osteoarthritis, it helps not only by strengthening cartilage and muscle but also by tackling the inflammation, metabolic changes and hormonal shifts that drive the disease.

Obesity is a major risk factor for osteoarthritis, and not merely because of the extra mechanical load on joints. High levels of inflammatory molecules in the blood and in joint tissues can degrade cartilage and accelerate disease.

For osteoarthritis, regular activity can counter this at a molecular level, lowering inflammatory markers, limiting cell damage and even altering gene expression.

Exercise first, surgery later

Currently there are no drugs that modify the course of osteoarthritis. Joint replacement surgery can be life-changing for some people, but it is major surgery and does not succeed for everyone.

Exercise should be tried first and continued throughout every stage of the disease. It carries far fewer side effects and brings many additional health benefits.

Osteoarthritis is not simply a matter of “worn out” joints. It is shaped by muscle strength, inflammation, metabolism and lifestyle.

Regular, targeted exercise addresses many of these factors at once – helping to protect cartilage, strengthen the whole joint and improve overall health. Before considering surgery, movement itself remains one of the most powerful treatments we have.

Clodagh Toomey receives funding from the Health Research Board (Ireland) for research in the area of osteoarthritis. She is affiliated with non-profit initiative GLA:D(r) (Good Life with osteoArthritis Denmark).

– ref. Joint pain or osteoarthritis? Why exercise should be your first line of treatment – https://theconversation.com/joint-pain-or-osteoarthritis-why-exercise-should-be-your-first-line-of-treatment-260638

Source: The Conversation – UK – By Will de Freitas, Environment + Energy Editor, The Conversation

This roundup of The Conversation’s climate coverage was first published in our award-winning weekly climate action newsletter, Imagine.

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As the world mourns Jane Goodall, the pioneering chimpanzee scientist and campaigner who died last week aged 91, it’s worth asking what chimpanzees can still teach us about climate change. They not only have a few tricks for surviving a warming planet – they’ve also helped to cool it.

Most of the world’s 200,000 or so wild chimpanzees live in the huge rainforests of west and central Africa, the second largest in the world.

As recently as 2,500 years ago, much of this rainforest had withered away, broken into scattered fragments by a sudden lengthening of the dry season. Yet within five centuries, the forest had largely recovered.

Trees didn’t do this by themselves.

Chimpanzees, among other species, had acted as the forest’s “proto-gardeners”. That’s according to Alex Chepstow-Lusty, a paleoecologist then the University of Cambridge (now at the University of Sussex).

Chepstow-Lusty looked at the oil palm tree, which “demands a lot of light and so thrives in open areas or in the gaps created in forests when the canopy opens up rather than in the dense centre”. This means it often acts as a “‘pioneer species’ allowing the forest to regrow”.

But, he notes a problem: the oil palm’s large seeds are too heavy to be blown in the wind. “They therefore need to be dispersed in the poo of animals such as chimpanzees which are able to swallow the large seeds and for whom the bright orange flesh can be an important part of the diet. And this is how chimps and other seed-dispersers played a crucial role in regenerating Africa’s rainforests.”

Without chimpanzees, the forest would have taken far longer to recover – if it ever did. “Maybe we need to consider the true value of chimp poo, and those that produce it”, says Chepstow-Lusty.

But if chimpanzees once helped the planet heal itself, today that partnership is under strain.

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Read more:
Chimpanzees once helped African rainforests recover from a major collapse

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Adaptation written in their genes

Across Africa’s mix of forest and savanna, chimpanzees have evolved with their habitats. Harrison J. Ostridge of UCL Genetics Institute and his co-authors recently wrote about their work with a team who collected faecal samples from “hundreds of wild chimpanzees across 17 African countries”.

They found different populations have developed distinct adaptations: those in wetter regions have to survive infectious diseases, for instance, while others have to cope with life in hotter and drier open woodland.

This, they suggest, means chimpanzee populations across Africa are “not interchangeable”. Genetic diversity is typically a form of resilience, but as climate zones shift and habitats shrink, some chimpanzees may find themselves trapped in the wrong place. And while it takes thousands of years for genes to change, the climate is changing in decades.

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Read more:
Chimpanzee genes have changed over time to suit local conditions – new study

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Variable habits, variable behaviour

If DNA adapts over millennia, behaviour can adapt within a lifetime.

A team from UCL, Harvard and Liverpool John Moores wrote about their work compiling data from 144 wild chimpanzee communities across Africa’s forests and savanna. They found populations that had learned to dig wells, or to take refuge from extreme heat in caves. Some chimpanzee populations used all sorts of tools, while others barely used any.

The common thread was an adaptation to local circumstances. “Chimpanzees meet variable habitats with variable behaviour”, in their words.

This flexibility may help chimpanzees weather the next degree or two of climate breakdown. But behavioural diversity depends on a strong social life. Young chimps learn by watching others, by playing and imitating. And if that social culture is lost, so is some of their ability to adapt to climate change.

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Read more:
Chimpanzees in volatile habitats evolved to behave more flexibly – it could help them weather climate change

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A cultural collapse

That same UCL–John Moores team have documented a “cultural collapse” in chimpanzees. “The more that humans had disturbed an area”, they write, “the less behavioural variants are exhibited by nearby chimpanzees”. Animals are forced to forage in smaller groups, with less long distance communication through hoots or drumming on tree trunks. This “lowers the chance of learning socially from one another” and makes it harder to spread any culture.

Why does it matter, they ask, “if the species is gradually merging into a single cultural entity that stretches all the way from Senegal to Tanzania”? After all, most animals don’t have distinct cultures.

One reason is that a loss of social learning makes chimpanzees more vulnerable: “A loss of behavioural diversity [could compromise how they respond] to changes in food availability and how they adapt to climate change.”

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Read more:
A chimpanzee cultural collapse is underway, and it’s driven by humans

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Carrying on Goodall’s legacy

Jane Goodall bridged science and society in a way very few others have managed since. One of those few is Ben Garrod, a professor of evolutionary biology and science engagement at the University of East Anglia. A BBC television presenter and a primate scientist, he’s worked with Goodall and her foundation and says we need more Jane Goodalls.

“There will be countless ways we can carry on with Jane’s legacy”, he writes, “but one of the most powerful is to encourage more of us to make science accessible for all of us”.

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Read more:
Why we need more Jane Goodalls

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– ref. When chimps helped cool the planet – https://theconversation.com/when-chimps-helped-cool-the-planet-267043

Source: The Conversation – UK – By Christina Wilkins, Lecturer in Film and Creative Writing, University of Birmingham

Shows about men still dominate our television screens. But the stories being told are starting to change, with more room for vulnerability and portrayals of male mental illness. These changes include explicit mentions of diagnostic categories and male characters with mental illnesses in the lead role.

In the last few years in the UK and the US, male-centred shows such as The Bear (2022-), Ted Lasso (2020-), Barry (2018-23), The Boys (2019-26), Succession (2018-23), Baby Reindeer (2024) and Slow Horses (2022-) have been hugely popular. It is telling that of these series, at least four explicitly deal with male mental illness.

While researching my new book, Male Mental Illness in Contemporary Culture (due out late 2025), I found that male mental illness is made much more explicit within the comedy genre, particularly in the UK.

For series in the US, male mental illness is more often used as a plot device rather than being the focus of the story itself. And even then, it may reinforce stereotypes. For example, the Netflix show Unstable (2023) focuses on Ellis (Rob Lowe) and his mental breakdown following the death of his wife. Very often his mental health struggle is presented as eccentricity and oddness, giving him an excuse to behave strangely rather than dealing with his experience.

These stereotypes emerge from the dynamics of the television industry, particularly in the US. Men historically outnumbered women in the industry three to one in US-produced television. Despite this improving in recent years to women taking 43% of the roles onscreen in US television, traces of the past remain. Much of the research focuses on US examples, with a gap around how men onscreen are presented in the UK.

With the overrepresentation of men, it might be assumed there is more variety of masculinity onscreen. However, research in 2017 into the depiction of men onscreen in the US has shown men often upholding old-fashioned ideals of masculinity, noting that the men on our screens are “likely to be shown as dominant and in the prime of their lives”.

For mental health and mental illness, this has an impact. Men’s expected roles in society conflict with their experience of mental illness.

Differences between cultures

There appears to be a difference in UK and US portrayals. In the US, recent series that are categorised as “about mental health” include Apple TV+’s Shrinking (from the team involved with Ted Lasso, another series that engages with male mental health) as well as Unstable.

While these shows are based on the idea of the central male protagonist struggling mentally, this is due to grief from the loss of their spouses. Their struggles are mainly communicated through eccentric behaviour, rather than engaging with their emotions.

By contrast, recent UK series that have explored male mental health and illness – still in the vein of comedy – have done so with more attention to the details of illness itself. One of the best examples is Big Boys (Channel 4, and now on Netflix), which follows Jack (Dylan Llewellyn) as he starts university.

Jack is trying to navigate the death of his father, coming out and starting a new chapter. But it is the portrayal of his friend Danny (Jon Pointing) that is the most interesting. Danny is a lad type, whose swagger functions as a central part of his character. But we’re also shown his struggle with depression, including the mundanities that aren’t always covered onscreen: the alarms for medication, the side effects of that medication, the friends who check in and help out during an episode.

Unlike other portrayals of men onscreen, Big Boys presents a character whose struggles aren’t just played for laughs. Instead, Danny’s character addresses the very real details of the mental illness experience.

The differences between the UK and the US could be down to how mental health is viewed in each country. Surveys in the UK found in 2021 that nearly three quarters of people believed stigma towards those with a severe mental illness has not improved in the last decade.

Even more recently, a survey by Mind in 2024 found that 51% of the UK population believes there is a great deal or fair amount of shame associated with mental health conditions. The specifics of this stigma are highlighted by other surveys, which have found that “negative attitudes towards people with mental illness [are] more common among men”.

The American response in some surveys looks different. In 2019, the American Psychological Association claimed that Americans were becoming more open about mental health. But the same survey found that a third of respondents still saw people with mental illness as someone to be scared of.

There are many similarities here between the way mental illness is viewed between the two cultures, with stigma remaining something to be countered, and a recurrent part of charity campaigns. The differences between the portrayals on television suggests something to do with understandings of masculinity and expectations of what male mental health and illness looks like.

For now, Big Boys offers something different. But there is still room for more portrayals to engage with the experience in more detail without resorting to stereotypes.

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Christina Wilkins does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. The evolution of male mental health in television – https://theconversation.com/the-evolution-of-male-mental-health-in-television-266318

Source: The Conversation – UK – By Alex Ford, Professor of Biology, University of Portsmouth

Most environmental scientists believe that chemical pollution can and is negatively affecting people and wildlife, according to my team’s recent survey.

We surveyed 166 environmental scientists across academia, government and industry and found that industry scientists working in environmental toxicology were reluctant to use behavioural studies when assessing the risk posed by chemicals. There are several possible reasons for their reticence.

As a society we have known for centuries that chemical pollutants can affect our behaviour. The terms “mad as a hatter” and “crazy as a painter” entered the English language due to observations of psychotic behaviour caused by occupational exposure to mercury and lead. Around the world, lead has been removed from water pipes because it can reduce cognitive ability in children.

Restrictions of alcohol and drug consumption exist while people are driving because it increases the risk of accidents. But previous research highlights that behaviour is rarely used to assess the effects of pollution on wildlife.

There are approximately 350,000 different chemicals in everyday domestic and industrial use. Before these chemicals are licensed for use, governments or industries conduct experiments to assess the potential risk to the environment.

Unfortunately in many incidences, chemicals have reached the market without a thorough assessment of the harm they may cause to the environment. That includes plastic additives – chemicals added to plastics to give them certain properties such a flexibility, heat resistance, colour and UV protection.

Scientists have estimated that there are over 16,000 chemicals known to be within plastics or used to make them. Two-thirds of these chemicals do not have sufficient data on their toxicity.

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Read more:
Lobbying in ‘forever chemicals’ industry is rife across Europe – the inside story of our investigation

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Toxicity tests typically involve a limited number of animals including fish, crustaceans and algae. They are exposed to particular chemicals to assess their effects on survival, growth and reproduction. As as means of protecting the wider environment, risk assessments determine what the safe levels of these chemicals might be in the environment.

However, they aren’t assessed to determine whether they change an animal’s behaviour. Studies into the effects of prescribed and illegal drugs taken to deliberately alter human behaviour has driven questions over their environmental consequences.

Many pollutants that mimic and act like hormones also alter behaviour. For example, synthetic oestrogens and androgens can alter the reproductive behaviour of fish. Antidepressants and anti-anxiety medications alter the behaviour of many aquatic organisms.

An animal’s behaviour is critical to its survival. A split-second decision while driving on the road may cause or prevent a traffic collision and could mean the difference between life or death. Similarly, if an animal isn’t behaving normally, it might struggle to escape predators, find food or attract mates.

Reasons for reluctance

We found there could be many reasons why industry toxicologists are reluctant to embrace behavioural studies.

First, industry scientists were more sceptical that behavioural studies are repeatable. Some expressed concern about the reliability of toxicity metrics.

While some scientists share these concerns, efforts are being made internationally to standardise methodology. The pharmaceutical industry already uses behavioural tests in drug design which suggests some acceptance to their credibility.

Second, all of the scientists we questioned agreed that adding behavioural tests to existing chemical contamination assessments would increase costs for both industry and government. Although it may affect profit margins, we argue that not adding behaviour to the suite of tools to assess chemical safety comes with cost to human health and the environment.

Industry may also be apprehensive about adopting behavioural testing due to fear of what scientists may find out about existing chemicals. Could there be a chemical in our everyday products that increases the likelihood of dementia, anxiety or depression?

For example, some scientists are starting to link pollution with incidences of neurological disorders, anxiety and some have correlated even higher rates of crime.

Developing internationally standard toxicity tests can take years if not decades, so existing tests need to incorporate behaviour. This will hopefully reduce time, costs and ethical concerns while at the same time maximising the available information to protect human health and the environment.

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Alex Ford has received funding from research councils, european union, regulatory authorities, NGOs and industry

– ref. Chemical pollutants affect wildlife and human behaviour. But industry toxicologists are reluctant to carry out tests, new survey reveals – https://theconversation.com/chemical-pollutants-affect-wildlife-and-human-behaviour-but-industry-toxicologists-are-reluctant-to-carry-out-tests-new-survey-reveals-266919

Source: The Conversation – UK – By Blanka Grzegorczyk, Senior Teaching Associate, Faculty of Education, University of Cambridge; Manchester Metropolitan University

Between 2013 and 2015, Malorie Blackman was Britain’s first black children’s laureate. Her young adult series Noughts and Crosses (2001-21) at once challenges and plays with the prevailing racial ordering of western life and thought.

Blackman’s series is set in an alternative Britain called Albion, where power is held by a dominant, black majority known as the “Crosses”, while the white “Noughts” are stigmatised minority subjects. In doing so, Blackman suggests that if we see difference as threatening or inferior, then any alternative worlds we imagine will just reflect our own culture. The upending of racial formations, the books seem to suggest, could result in an equally powerful, reverse form of oppression.

Most contemporary criticism and the book’s most well-known adaptations (at the Royal Shakespeare Company and for the BBC) treat Blackman’s series as a case study of anti-racist political allegory, counterfactual historical, or dystopian fiction. Their focus tends to be on the forbidden romance between Callum McGregor, an increasingly disaffected and conflicted working-class Nought, and a Cross politician’s wealthy and privileged daughter, Persephone “Sephy” Hadley.

But it is also possible to read Noughts and Crosses specifically as an attempt to show systems of oppression at work: how they prop up (neo-)imperialist power, enable racial segregation and traumatise people.

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This article is part of Rethinking the Classics. The stories in this series offer insightful new ways to think about and interpret classic books and artworks. This is the canon – with a twist.

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Noughts and Crosses isn’t just a dystopian story – it’s a critical dystopia, meaning it aims to inspire political thought and change. Critical dystopias don’t usually show us a better world; instead, they make us think about how one might be created.

What makes a critical dystopia powerful is how it mixes everyday life with moments of fear or tension. This mix makes familiar situations feel unsettling, encouraging readers to see the world differently. It pushes them to question unfair or harmful systems and imagine better alternatives.

The power of secrets

In Noughts and Crosses, Callum and Sephy repeatedly come up against suppressed truths and hidden histories. The truth behind Callum’s sister Lynette’s fragile mental state, for example, is revealed to be a vicious racist attack on her and her Cross boyfriend prior to the events of the novel. But by the time Callum learns this secret, it is too late to stop the events leading to Lynette’s suicide, which draws Callum’s family deeper into a terrorist militia.

The novel’s constant use of hidden knowledge draws attention to the atomised condition of life in a racially divided state. Particularly significant here is a picture of the family unit in which dreams, aspirations and motivations are only partially knowable – and never completely fulfilled. Tragedies such as those experienced by the McGregor family galvanise the tribalist rhetoric of a segregated society.

On the other hand, the novel shows that through discovery, its young characters become more sceptical about any stories that they have been handed by that social order. When Sephy learns that she has an older half-brother, she concludes: “Nothing in [her] life was a fact. There was nothing to cling on to.”

This is also the case when Callum struggles to “find something of sense to hold on to” after his brother Jude’s admission that he became more radicalised due to learning another crucial family secret – that their great-grandfather was a Cross.

Noughts and Crosses does explore, at times, what happens when marginalised voices are repositioned as central. But it also seeks to heal society’s divisions while challenging its self-defeating logic and suggests that one way to do so is by revealing the truth.

In the novel’s final passages, the reader learns that Sephy has defied her parents’ wishes and given birth to her and Callum’s baby. This can be read as a suggestion that their – and perhaps our – social divisions can be healed, eventually, and that a less divided future is possible.

At the same time, however, Blackman sometimes seems to make the truths told in the novel – like what Callum reveals to Sephy as the “biggest secret of them all” – clearer to us, the readers, than her own characters. This is not just a matter of plot, but one of effect. As readers, we start to become immersed in a rush of twists and unravellings, crossings and unwindings, until we can almost glimpse a different kind of reality, beyond the segregated world of the novel.

In the end, the novel is not recentring one part of society at the expense of another – it is recentring us, the reader, and how we think about its world and ours, by inducting us into the secrets of others. In this context, the act of writing – and reading – is an act of hope.

This is the art of the critical dystopia: the further we read, the more we become engrossed in the shadow texts, or truths of which the characters themselves might be unaware, about how society could be fractured, transformed and remade.

Beyond the canon

As part of the Rethinking the Classics series, we’re asking our experts to recommend a book or artwork that tackles similar themes to the canonical work in question, but isn’t (yet) considered a classic itself. Here is Blanka Grzegorczyk’s suggestion:

Haunted by real-world histories, and specifically by the repeat patterns of the colonial past and neocolonial present, S.F. Said’s alternative Britain in his critical dystopia Tyger (2022) is one where the British empire still rules the world, and slavery was never abolished.

The novel brings its exposé of the terrors of the imperial past to bear on the present moment.

In its exploration of art- and story-based forms of oppositional agency, the novel highlights British Muslim characters Adam and Zadie’s calls for a future where a truly sustainable and equal way of living might be possible. At the same time, it shows them acting as if that hoped-for, radically transformed world already exists in the present.

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This article features references to books that have been included for editorial reasons, and may contain links to bookshop.org. If you click on one of the links and go on to buy something from bookshop.org The Conversation UK may earn a commission.

Blanka Grzegorczyk does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Malorie Blackman’s Noughts and Crosses uses critical dystopia to challenge us to build a better future – https://theconversation.com/malorie-blackmans-noughts-and-crosses-uses-critical-dystopia-to-challenge-us-to-build-a-better-future-253879

Source: The Conversation – UK – By Beverley O’Hara, Lecturer in Nutrition, Leeds Beckett University

Since Wegovy received approval as a weight loss treatment in 2021, there has been huge demand for GLP-1 drugs. These drugs reduce hunger and suppress the “food noise” that can make it difficult to lose weight.

But while these drugs have been a gamechanger for many who have struggle to lose weight, it wasn’t long before the backlash against them started. In response, high-profile celebrities such as Serena Williams have opened up about using these drugs in the hopes that it would counter the rising stigma of using them.

Sadly, it’s probably going to take more than celebrity endorsement to change the way society views people who are overweight. Weight-loss drug stigma is just the latest form of “fatphobia”.

Weight and obesity have long been stigmatised in our society. Obesity is even considered by some to be a moral failing, rather than a result of an person’s unique biology interacting with complex societal and environmental forces. This misconception has contributed to weight stigma and weight bias, where people may hold negative attitudes towards people who are overweight and may even discriminate against them.

While popular initiatives in recent years have aimed to advocate for the acceptance of all bodies regardless of size (such as the body positivity movement), stigma against larger bodies is still the norm, as our work has shown.

Earlier this year, we conducted research on perceptions of health and weight. As part of our survey, we asked 143 participants to describe photos of adults of varying body weights. These photos depicted people engaging in so-called “healthy” and “unhealthy” behaviour – such as exercising or lying on a couch.

The results were stark. Photos of slender people elicited more friendly or warm comments from participants. However, photos of people with obesity were consistently described using negative and stigmatising language, such as “lazy”, “dirty”, “slobbish” and “unappealing”.

The message was clear. You’re only as healthy and desirable as your body size. Even though body size is not a good indicator of metabolic health, our work shows that slimness is still highly valued and seen as a marker of being healthy – regardless of a person’s actual health status.

Although most participants understood that the causes of obesity are complex and not just due to lifestyle choices, this insight did not affect their attitudes towards people with obesity. Weight bias still appears to be a permissible form of discrimination to some.

With the use of weight loss drugs becoming increasingly more common, one research team hypothesised that these drugs might change attitudes towards obesity – helping our society see that weight is more related to biology than willpower. They conducted two surveys to uncover whether weight loss drugs had any effect on reducing weight bias.

The results from that survey showed that nothing has changed when it comes to weight stigma. Participants overwhelmingly thought that obesity is controllable through willpower – and that the use of weight loss drugs is unfair and the “easy way out”.

Judging people for taking weight loss drugs is merely a new variation of weight stigma. People are first negatively judged for being overweight in the first place – but then judged again for undergoing the “wrong sort” of treatment.

Although significant and long-lasting weight loss through behavioural changes alone is extremely rare, taking weight loss drugs is seen by some as “cheating”.

What people want to see is “good old-fashioned hard work”. Research shows that people are more likely to see someone in a negative light if they don’t think that person is putting in the effort to lose weight.

The “right way” is often thought of as exercising willpower, being more physically active and eating less. Using weight-loss drugs is seen by some as evidence that people with obesity are “too weak” or “too lazy” to lose weight in a way that is perceived as being correct.

The harm of GLP-1 stigma

Using a GLP-1 drug as a weight loss method is judged more harshly than losing weight through traditional methods.

Fear of this negative judgement is reportedly driving some users to take GLP-1 drugs in secret, even hiding their use from loved ones.

We currently don’t know the full scale and effect of weight loss drug stigma. It’s possible that it could deter people from seeking treatment with these medications or even increase social isolation as users withdraw for fear of being judged.

Weight stigma is already harmful to physical and psychological health – leading to poorer wellbeing and even depressive symptoms. The burden of keeping use of these drugs private could further increase risk of these harms.

Worryingly, it could even stop people from seeking medical attention for any side-effects they may experience, whether that’s mild gastrointestinal problems to rare, potentially severe complications such as thyroid tumours, severe gastrointestinal complications and a rare eye condition that may result in vision loss.

People using weight-loss drugs must also navigate the potential psychological aspects of GLP-1 treatment. Alongside negative judgement of taking the drugs, there may be anxiety about supply and affordability, the spectre of weight regain and an altered relationship with food.

It’s darkly ironic that, despite the increased awareness and use of GLP-1 drugs in our society, weight stigma is still so prevalent. The social, emotional and physical effects of using these drugs amounts to a costly commitment and is not, in fact, an “easy way out”.

Beverley O’Hara is affiliated with The Association for the Study of Obesity.

Jordan Beaumont receives funding from NIHR. He is affiliated with the Association for the Study of Obesity.

– ref. Weight loss drug stigma shows society still holds negative attitudes towards body weight and obesity – https://theconversation.com/weight-loss-drug-stigma-shows-society-still-holds-negative-attitudes-towards-body-weight-and-obesity-265019