Category: English

Source: The Conversation – UK – By Timothy Hearn, Lecturer, University of Cambridge; Anglia Ruskin University

An upside-down jellyfish drifts in a shallow lagoon, rhythmically contracting its
translucent bell. By night that beat drops from roughly 36 pulses a minute to nearer 30, and the animal slips into a state that, despite its lack of a brain, resembles sleep.

Field cameras show it even takes a brief siesta around noon, to “catch up” after a disturbed night.

A new Nature Communications study has tracked these lulls in cassiopea jellyfish, which belong to a 500 million year-old lineage, as well as in the starlet sea anemone nematostella. The study findings may help settle a long-running debate among biologists about what sleep is for.

Does sleep conserve energy, consolidate memories – or do something more biologically fundamental? Until recently, most evidence for a “house-keeping” role for sleep came only from vertebrates.

When mice sleep, brain and spinal cord fluid surges through the brain and washes away metabolic waste. And a 2016 mouse study found that some types of DNA breaks are mended more quickly during sleep. Time-lapse imaging in a 2019 study of zebrafish showed that sleep lets neurons (nerve cells) repair DNA breaks that build up during waking hours.

The new study showed for the first time that the same process occurs in some invertebrates. That while the jellyfish and sea anemone are awake, DNA damage accumulates in their nerve cells and when they doze, that damage is repaired.

The work pushes the origins of sleep back more than 600 million years, to before the cnidarian branch (jellyfish, anemones, corals) split from the line that led to worms, insects and vertebrates roughly 600–700 million years ago. It also gives weight to the idea that sleep began as a form of self-defence for cells.

The new work moves the discussion to creatures whose nervous systems are much simpler than ours and are little more than thin nets. If sleep repairs their neurons too, that function is probably fundamental because simpler nervous systems evolved first.

The researchers first had to figure out when a jellyfish or anemone is asleep. This is surprisingly tricky: even when they rest, bell muscles keep twitching or the polyp drifts in slow motion. To do this they filmed the animals under infrared light and flashed white light at them or a pulse of food (a tiny squirt of liquid brine-shrimp extract).

Jellyfish that had been pulsing below 37 beats per minute for at least three minutes, and anemones that had stayed still for eight minutes, reacted more slowly. This meets the “reduced responsiveness” criterion for sleep, which is the same across the animal kingdom.

Next, the scientists stained nerve cells in tissue taken from jellyfish in a lab tank to mark where DNA breakages happened. The number of breakages peaked at the end of each species’ active spell (mid-morning for the jellyfish and late afternoon for the anemone) and dropped after a long rest.

When the scientists kept the animals awake by changing the tank’s water currents, both the DNA breaks and the next day’s sleeping time increased, similar to classic “sleep rebound” in humans where your body catches up on sleep.

To test cause and effect, the team shone ultraviolet-B light, which damages DNA, on the animals. This treatment doubled the number of DNA breaks within an hour and prompted extra sleep later the same day. When the animals had dozed, the breaks reduced back toward baseline and the jellyfish resumed their usual daytime rhythm.

Melatonin, the overnight hormone familiar to jet-lag sufferers, was added to the tank water and caused both species to doze during what should have been their busiest stretch (daytime for the jellyfish, night-time for the anemone), leaving their usual rest period unchanged.

The new finding is surprising because melatonin’s soporific role was thought to have evolved alongside vertebrates with centralised brains and circadian rhythms that respond to light cues. Seeing it work in a brainless animal suggests that this evolution took place much longer ago.

Putting these pieces together, it seems wakefulness gradually stresses the DNA in nerve cells. Sleep offers a period of sensory deprivation during which repair enzymes that stitch or swap the components of DNA can work unimpeded.

This logic fits with experiments in fruit-flies and mice which have linked chronic sleeplessness to neurodegeneration. Insomnia has also been linked to build-ups of reactive oxygen molecules (highly reactive by-products of normal metabolism that can punch holes in DNA, proteins and cell membranes).

If jellyfish need sleep to keep their nerve nets intact, the need to sleep probably predates the evolution of brains, eyes and even bodies that are the same on both left and right sides. In evolutionary terms, a nightly repair window could have been vital. Ancient organisms that skipped it may have accumulated mutations in irreplaceable neurons and slowly lost control of movement, feeding and reproduction.

The new study tracked two species in the lab and one in a Florida lagoon, but cnidarians live in many different light levels and temperatures. To be able to generalise this finding, future work will need to confirm that DNA-repair during sleep happens in similar animals that live in different conditions such as cold, deep or turbid waters.

Does this study settle the debate? Not entirely. Sleep almost certainly carries more than one benefit. Tasks such as memory consolidation could have been layered onto an ancient physiological maintenance programme as nervous systems grew more complex.

Yet the new findings strengthen the view that guarding DNA is a core purpose of sleep.

Timothy Hearn 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. What an ancient jellyfish can teach us about the evoution of sleep – https://theconversation.com/what-an-ancient-jellyfish-can-teach-us-about-the-evoution-of-sleep-273307

Source: The Conversation – UK – By Steven David Pickering, Honorary Professor, International Relations, Brunel University of London

Academic freedom is often described as a cornerstone of democratic society. Politicians regularly claim to defend it, universities invoke it in mission statements and most members of the public say they support it in principle.

So why does it provoke such intense disagreement once it becomes concrete? At first glance, these disputes look like arguments about universities. But our research suggests something else is going on. Public disagreements over academic freedom are not simply about campus policy. They reflect deeper divides over political ideology and trust in expertise.

Debates about academic freedom have become increasingly prominent in the UK. New free speech legislation to protect academic freedom in universities was introduced in 2025. Disputes over offensive research, controversial speakers or international partnerships routinely make headlines.

Similar tensions exist elsewhere, even if they are less visible. In Japan, for example, academic freedom is formally protected in article 23 of the constitution, but scholars often report subtle pressures to avoid politically sensitive topics.

In a new study, we surveyed over 3,300 people in the UK and Japan to examine how citizens understand academic freedom when it is presented in concrete terms rather than abstract slogans.

Instead of asking whether people support “academic freedom” in general, we asked how much they agreed or disagreed with specific scenarios. These included whether universities should protect research that causes offence, and whether academics should be free to publish controversial findings. We also asked whether universities should collaborate with multinational corporations or political regimes accused of human rights abuses.

This approach matters. In surveys, people often express strong support for free inquiry in the abstract. But once academic freedom is tied to real-world trade-offs, such as offence, harm, reputation or political controversy, agreement tends to fracture.

Across both countries, political ideology emerged as one of the strongest predictors of attitudes toward academic freedom.

Right-leaning respondents were consistently more supportive of academic freedom. They were more likely to oppose restrictions on offensive research and more likely to agree that academics should be protected even when their work provokes controversy. This pattern appeared not only in the UK, where universities are deeply entangled in culture-war debates, but also in Japan, where such disputes are less visible in public life.

Left-leaning respondents, by contrast, were more likely to emphasise accountability. They tended to support limits on research perceived as offensive or harmful, reflecting greater concern for social sensitivity and the potential impact of academic work on marginalised groups.

These differences suggest that academic freedom is not a single, universally understood value. Instead, people interpret it through broader political worldviews. For some, it primarily means freedom from interference. For others, it is inseparable from social responsibility.

Trust in scientists matters

Trust also plays a crucial role. In both countries, people who trusted scientists more strongly were more likely to support academic freedom, particularly when asked whether researchers should be protected regardless of whether their findings cause offence.

Trust appears to act as a kind of permission structure. When people believe scientists are acting in good faith, they are more willing to tolerate controversial outcomes.

This effect was especially pronounced in Japan. There, trust in scientists was one of the strongest predictors of support for academic freedom across multiple scenarios. This likely reflects Japan’s institutional culture. Deference to expertise remains relatively high and political conflict over universities is more muted than in the UK.

In Britain, by contrast, trust in scientists mattered most when academic freedom was framed as protection for individual researchers, but less so when questions involved partnerships with controversial regimes. In those cases, trust was more conditional. This suggests that even trusted experts are expected to exercise judgement about ethical boundaries.

Taken together, these findings point to a deeper pattern. Public attitudes toward academic freedom are structured by two competing logics.

One emphasises autonomy. This is the idea that scholars must be insulated from political and social pressure in order to pursue knowledge freely. The other emphasises accountability: the belief that universities, as publicly funded institutions, should be responsive to social norms and moral concerns.

Most people do not fully embrace one logic or the other. Instead, they shift between them depending on the issue at hand. Many support free research in principle but draw lines when offence, ethics or international politics enter the picture.

This helps explain why debates over academic freedom so often feel polarised and unresolved. They are not simply disputes about policy details. They are disagreements about which values should take priority when liberal principles collide.

These findings have important implications.

First, they suggest that appeals to “academic freedom” alone are unlikely to persuade sceptics. Because people understand the concept differently, arguments that assume a shared meaning often talk past their audience.

Second, they highlight the importance of trust. Where confidence in scientists and universities is high, support for academic autonomy is more resilient. Where trust erodes, demands for oversight and restriction grow stronger.

Finally, disputes over academic freedom reflect broader tensions within democratic societies between liberty and accountability. These tensions are not new, but they are becoming more visible as universities sit at the centre of political and cultural change.

Rather than asking whether academic freedom is under threat, a better question may be this: how can institutions sustain public trust while defending the autonomy that makes academic inquiry possible in the first place?

Steven David Pickering received funding from the Japan Society for the Promotion of Science (JSPS, grant reference JPJSJRP 20211704) and the UK Research and Innovation’s Economic and Social Research Council (UKRI-ESRC, grant reference ES/W011913/1).

Yosuke Sunahara receives funding from Japan Society for the Promotion of Science (grant reference JPJSJRP 20211704.

Martin Ejnar Hansen 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. How political leanings affect views on academic freedom – new research – https://theconversation.com/how-political-leanings-affect-views-on-academic-freedom-new-research-273408

Source: The Conversation – UK – By Thomas Lockwood, PhD Researcher in Politics, York St John University

Suella Braverman’s decision to defect to Reform UK is not just another blow to Kemi Badenoch’s attempt to stabilise the Conservatives after their 2024 defeat. It also changes what Reform is being judged on.

Earlier this month, Badenoch sacked Robert Jenrick from the shadow cabinet for plotting to defect to Reform. Hours later, he did just that. Braverman’s move takes Reform’s number of MPs to eight. Party leader Nigel Farage has said Reform had been in talks with her for a year.

At this point, though, Reform is at risk of absorbing so many former Tories that it starts to look like the establishment it denounces. This recruitment spree rewrites the insurgent brand.

Reform’s leadership will understandably celebrate Braverman’s arrival as a serious coup. She is a former home secretary and a national media figure. Her departure is an unmistakable signal that the Conservative right is fragmenting. The Times reports she told supporters it felt like she had “come home”, but there is a basic strategic tension here. Reform has thrived by arguing that British politics is run by a closed circle of insiders who fail repeatedly and then reshuffle into new jobs. A rapid intake of ex-ministers risks making Reform look less like a clean break and more like a migration route for political careers.

That attack line is already being deployed. After former chancellor Nadhim Zahawi’s switch earlier this month, the Liberal Democrats described Reform as “a retirement home for disgraced former Conservative ministers”. The same basic charge has followed Braverman’s move: critics argue that people who helped shape the recent Conservative record are now trying to rebrand themselves inside Reform rather than account for that record.

For Reform, then, the immediate gain in publicity comes with a reputational cost: the party becomes easier to frame as a collection of defectors rather than a coherent alternative.

The May deadline: Reform knows the danger

If Reform were confident that any defection is good news, it would have no need for a cut-off date. But Farage has set the local elections date of May 7 as the latest date he will take Conservative switchers. After that, he believes his party would start to look like “a rescue charity for every panicky Tory MP”.

That is revealing. It implies Reform is trying to capture the benefits of defections (experience, profile, the aura of inevitability) while limiting the downside (brand dilution, factional chaos, accusations of being “Tories in new colours”). A deadline is, in effect, an admission that there is such a thing as too many ex-Tories… or at least too many arriving too quickly.

The deeper issue is organisational. Recruiting MPs is not the same as building a party machine. Defectors bring personal followings, constituency operations, donor networks and ideological baggage. They can add reach but they can also add volatility, especially if Reform’s appeal relies on projecting discipline and clarity.

And internal tensions are not theoretical. Braverman and Jenrick are not merely Conservatives who happen to have drifted rightwards. They were also senior figures in a government that Reform has attacked as incompetent and deceitful.

That is why a July 2025 post on X by Zia Yusuf (widely circulated as Braverman joined) lands so sharply. In the post, the head of policy at Reform UK referred to the Conservative government’s handling of an Afghan data leak and secret resettlement, asking “who was in government?”, and then named Braverman as home secretary and Jenrick as immigration minister.

The point isn’t whether Yusuf’s earlier argument was fair or unfair. It’s that it feeds an “own goal” narrative. Reform’s senior figures have recently depicted these people as emblematic of the failures of the Conservative state, and now the party is inviting them into the tent.

That forces Reform into a delicate position. If it embraces defectors uncritically, it weakens its anti-establishment brand. If it keeps attacking them, it destabilises its own recruitment strategy.

Braverman’s seat: opportunity and risk

Braverman’s own constituency, Fareham and Waterlooville, illustrates why Reform wants converts of her stature and why the strategy can backfire.

On official local results for the 2024 general election, Braverman won with 35% of the vote; Reform placed fourth on 18%, behind Labour (23%) and the Liberal Democrats (19%).

That is the kind of compressed result Reform dreams about: a sizeable right-populist base already present, plus a Conservative vote that if transferred could turn a marginal into a secure Reform seat. From this perspective, defections are not just PR. They are an attempt to solve Reform’s hardest electoral problem: converting diffuse national support into winnable constituency coalitions.

But the same numbers show the danger. If Braverman fails to bring a large share of Conservative voters with her, the most likely short-term effect is to make the seat more competitive for her opponents through vote fragmentation and tactical voting. Defections can therefore produce a paradox: they make Reform look bigger nationally while making individual contests messier locally.

And at the national level, the risk is huge. Reform’s central claim – that it is the “alternative” to a failed political class – is now colliding with the reality of who it is recruiting from that class.

If Reform wants to remain a pure insurgency, it must keep its distance from establishment figures and prioritise new candidates. If it wants to look like a credible government-in-waiting, it will keep collecting experienced politicians, but it must then accept the costs – intensified scrutiny, more ammunition for opponents, and the constant suspicion that it is simply rebranding Conservatism rather than replacing it.

Thomas Lockwood 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. Suella Braverman defects: is Reform becoming a magnet for Tory baggage? – https://theconversation.com/suella-braverman-defects-is-reform-becoming-a-magnet-for-tory-baggage-274344

Source: The Conversation – UK – By Thom Wilcockson, Senior Lecturer in Psychology, Loughborough University

The earliest signs of dementia are rarely dramatic. They do not arrive as forgotten names or misplaced keys, but as changes so subtle they are almost impossible to notice: a slightly narrower vocabulary, less variation in description, a gentle flattening of language.

New research my colleagues and I conducted suggests that these changes may be detectable years before a formal diagnosis — and one of the clearest examples may lie hidden in the novels of Sir Terry Pratchett.

Pratchett is remembered as one of Britain’s most imaginative writers, the creator of the Discworld series and a master of satire whose work combined humour with sharp moral insight. Following his diagnosis of posterior cortical atrophy, a rare form of Alzheimer’s disease, he became a powerful advocate for dementia research and awareness. Less well known is that the early effects of the disease may already have been present in his writing long before he knew he was ill.

Dementia is often described as a condition of memory loss, but this is only part of the story. In its earliest stages, dementia can affect attention, perception and language before memory problems become obvious. These early changes are difficult to detect because they are gradual and easily mistaken for stress, ageing or normal variation in behaviour.

Language, however, offers a unique window into cognitive change. The words we choose, the variety of our vocabulary and the way we structure description are tightly linked to brain function. Even small shifts in language use may reflect underlying neurological change.

In our recent study, we analysed the language used across Terry Pratchett’s Discworld novels, examining how his writing evolved over time. We focused on “lexical diversity” — a measure of how varied an author’s word choices are — and paid particular attention to adjectives, the descriptive words that give prose its texture, colour and emotional depth.

Across Pratchett’s later novels, there was a clear and statistically significant decline in the diversity of adjectives he used. The richness of descriptive language gradually narrowed. This was not something a reader would necessarily notice, nor did it reflect a sudden deterioration in quality. Instead, it was a subtle, progressive change detectable only through detailed linguistic analysis.

Crucially, the first significant drop appeared in The Last Continent, published almost ten years before Pratchett received his formal diagnosis. This suggests that the “preclinical phase” of dementia — the period during which disease-related changes are already occurring in the brain — may have begun many years earlier, without obvious outward symptoms.

This finding has implications that extend far beyond literary analysis. Dementia is known to have a long preclinical phase, during which opportunities for early intervention are greatest. Yet identifying people during this window remains one of the biggest challenges in dementia care.

Linguistic analysis is not a diagnostic tool in itself, and it would not work equally well for everyone. Factors such as education, profession, writing habits and linguistic background all influence how people use language. But as part of a broader approach — alongside cognitive tests, brain imaging and biological markers — language analysis could help detect early risk in a non-invasive and cost-effective way.

Importantly, language data already exists. People generate vast amounts of written material through emails, reports, messages and online communication. With appropriate safeguards for privacy and consent, subtle changes in writing style could one day help flag early cognitive decline long before daily functioning is affected.

Why early detection matters

Early detection matters more than ever. In recent years, new drugs for Alzheimer’s disease have emerged that aim to slow disease progression rather than simply manage symptoms. Drugs such as lecanemab and donanemab target amyloid proteins that accumulate in the brain and are thought to play an important role in the disease. Clinical trials suggest these treatments would be most effective when given early, before significant neuronal damage has occurred.

Identifying people during the preclinical phase would allow people and their families more time to plan, access support and consider interventions that may help slow progression. These may include lifestyle changes, cognitive stimulation and, increasingly, new drugs to slow the disease progression.

More than a decade after his death, Terry Pratchett continues to contribute to our understanding of dementia. His novels remain deeply loved, but hidden within them is another legacy: evidence that dementia may leave its mark long before it announces itself. Paying closer attention to language — even language we think we know well — could help transform how we detect, understand and ultimately treat this devastating condition.

The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.

– ref. Terry Pratchett’s novels may have held clues to his dementia a decade before diagnosis, our new study suggests – https://theconversation.com/terry-pratchetts-novels-may-have-held-clues-to-his-dementia-a-decade-before-diagnosis-our-new-study-suggests-273777

Source: The Conversation – UK – By Andrew Gawthorpe, Lecturer in History and International Studies, Leiden University

Another US citizen has allegedly been killed by immigration agents in Minnesota, raising tensions between state and federal governments. The actions of the federal agencies involved has drawn fierce criticism not only from former Democratic presidents Barack Obama and Bill Clinton, but also America’s powerful pro-gun lobby, the National Rifle Association (NRA).

If you were to think it unusual that the people named in the previous sentence appear to be on the same side over this issue, you’d be right. But these aren’t usual times in America.

Video footage taken at the scene reportedly shows agents of the US Customs and Border Protection (CBP) – working with the Immigration and Customs Enforcement Agency (ICE) in Minnesota to detain people they suspect of being illegal migrants – tackling 37-year-old nurse, Alex Pretti.

The footage reportedly shows they wrestled him to the ground, beat him and apparently removed a handgun from a holster he was wearing, before firing ten shots at him.

Since his killing a lot of attention has focused on his gun. Carrying a handgun, whether openly or holstered, is legal in Minnesota, and Pretti had a license for his gun. So he was perfectly within his rights to be carrying it. And there is nothing to suggest from the footage that he attempted to draw it or use it while being tackled by the ICE agents.

Of course, in the United States, the right to keep and bear arms – the second amendment – is a pretty big deal to a lot of people, especially conservatives. So when various figures in the Trump regime suggested that CBP agents had been justified in shooting Pretti because he was carrying a holstered weapon, they provoked outrage from gun rights activists. And, significantly, many of these people are usually on the same page as the White House about pretty much anything.

First there was FBI director Kash Patel, who told Fox News: “You cannot bring a firearm loaded with multiple magazines to any sort of protest that you want.” Dead wrong, replied the Minnesota Gun Owners Caucus and the group Gun Owners of America – you’re legally entitled to bring a gun to a protest.

Then a Trump-appointed district attorney waded in, arguing: “If you approach law enforcement with a gun, there is a high likelihood they will be legally justified in shooting you.”

This drew a rebuke from the NRA, one of the most prolific and important right-wing groups in America and a big donor to Trump’s campaigns, which replied that: “This sentiment … is dangerous and wrong. Responsible public voices should be awaiting a full investigation, not making generalizations and demonizing law-abiding citizens.”

The problem that the Trump regime has is that it appears from abundant video evidence that Pretti was not handling his gun irresponsibly. He wasn’t waving it around, he wasn’t threatening anyone, in fact he wasn’t even touching it. He didn’t approach the federal agents – they appeared to pile on him. And he was disarmed of his holstered weapon by one of them before he was killed.

Second amendment vs tyrannical government

The reason that this touches such a raw nerve, even with many people who usually support Trump’s agenda, is that this cuts to the core of what the second amendment is about. In the eyes of the right, the amendment’s whole legitimacy rests on the idea that it allows the populace to arm in order to protect itself against a tyrannical government.

This means that Pretti was doing exactly what second amendment advocates say they need guns for. And while some gun rights advocates may have been willing to keep quiet while federal agents were trampling on the rights of migrants and brown-skinned citizens, the murder of Pretti is a bridge too far.

That’s not to say that the gun lobby is turning on the Trump administration – at least, not yet. But it is notable that ICE’s outrages (and those of the related Customs and Border Protection Agency) are becoming so hard to ignore that they’re increasingly drawing opposition not just from the left but also from traditionally right-wing groups.

The NRA is not about to flip and start fundraising for the next Democratic party presidential candidate. But its willingness to call out the regime is unusual to say the least. And it increases pressure on Trump to change course and damages the credibility of key people in the regime among conservatives.

The whole sequence of events also reveals something more concerning – the fact that more and more people in America on both left and right are carrying weapons. The idea of arming for self-defense has been quietly gaining ground in left-wing circles for around a decade.

Gun clubs have sprung up to serve LGBTQ+ people, black people, white liberals – anyone who fears they might one day be a target of violence from the Trump-ified federal authorities or right-wing militia. Nearly one-third of self-identified liberals now live in a gun-owning household.

And while it’s hard to find fault with their fears, this is another reason why America’s knife-edge politics is so terrifying. What happens when things fall apart in a country in which hatred and fear have driven so many people to arm themselves?

Let’s hope that Alex Pretti’s death serves as a reminder of the importance of stepping back from the brink rather than pushing the country closer to it.

A version of this article also appears on the author’s Substack series, America Explained.

Andrew Gawthorpe is affiliated with the Foreign Policy Centre, a London-based think tank.

– ref. Shooting of Alex Pretti in Minneapolis has put America’s gun lobby at odds with the White House – https://theconversation.com/shooting-of-alex-pretti-in-minneapolis-has-put-americas-gun-lobby-at-odds-with-the-white-house-274343