Category: English

Source: The Conversation – UK – By Bryce Stewart, Associate Professor, Marine Ecology and Fisheries Biology, University of Plymouth; Marine Biological Association

Cold spray whipped off the ropes as a diesel engine throbbed in the background. One by one, empty shellfish pots came over the side of the fishing boat, occasionally containing the remnants of crab and lobster claws and carapaces. Something strange was going on.

Then the culprit revealed itself – a squirming orange body surrounded by a writhing tangle of tentacles. A few minutes later, three more of these denizens of the deep came up in a single pot, and then, incredibly, a final pot rose from the water completely rammed full of them, more than a dozen together in a squirming mass.

This was a familiar scene off the south coasts of Devon and Cornwall early last year, as a bloom of the common octopus (Octopus vulgaris) emerged, the first time anything like this had been seen for 75 years. In fact, commercial catches of common octopus in 2025 were almost 65 times higher than the recent annual average. A new report now sheds light on these blooms: their history, the causes and the consequences.

The common octopus, despite the name, is not normally common in British waters. Instead, it favours the warmer climes of southern Europe, the Mediterranean and north Africa. But, occasionally, such as in 1900, 1950 and now 2025, numbers explode off the south-west coast of England, changing marine food chains and disrupting the local fishing industry.

Common octopuses take the ultimate “live fast, die young” approach to life. Despite the large size they can attain, they generally only live for less than two years, with females dying after their eggs hatch. The males also die after breeding. This means octopus populations are highly affected by changes in environmental conditions.

Octopus blooms have previously been rare in the UK, but emerging evidence from long-term marine monitoring of the western Channel suggests that these episodes coincide with sustained periods of unusual warmth in both the ocean and atmosphere.

These “marine heatwaves” can stimulate rapid population growth, whether the octopus are locally established or newly arrived from the south. These warm conditions are often accompanied by unusually low salinity in coastal waters, a signal that points to fresher water entering the region. While salinity itself is unlikely to drive the outbreaks, it serves as a valuable tracer of the water’s origin.

The fresher conditions may stem from high river flow from major French Atlantic rivers such as the Loire, or from prolonged easterly winds over the Channel during the cooler months (October to March). These processes could help transport octopus larvae across the Channel from northern France and the Channel Islands.

Taken together, the combination of warmth, altered circulation and low-salinity signatures suggests that climate-driven shifts in ocean and atmospheric dynamics underpin these outbreaks.

From crisis to opportunity?

Those early scenes of octopus consuming catches in crab and lobster pots continued as 2025 rolled on. But they didn’t just stop at crustaceans. Piles of empty scallop shells were found in many pots, sometimes with remnants of flesh still attached.

Scallops don’t normally go into crab and lobster pots (unless they have lights in them, which these ones didn’t), so the only explanation is that octopus were actively putting scallops in pots to stock up their larder, consuming them at leisure later.

However, fishers are nothing if not adaptable. They soon realised that there was a lucrative export market for octopus and began targeting them. One boat fishing out from Newlyn in Cornwall brought home over 20 tonnes of octopus, worth £142,000, from just three days fishing.

Between £6.7 million and £9.4 million worth of common octopus was landed on the south coast of the UK from January to August 2025. However, not all fishers benefited, and for most boats, octopus catches suddenly dropped off in August. With other shellfish fisheries also declining dramatically last year – lobsters by 30% and brown crabs and scallops by over 50% – many fishers worry about a future in which there is nothing left to catch.

So, what does the future hold? Given the link with climate change, the extensive reports of octopus breeding and a recent appearance of juvenile octopuses in UK waters, the continued presence of the common octopus seems likely.

If a bloom the size of last year’s occurs again soon, future fisheries should be guided by sustainable and ethical principles that help diversify opportunities for fishing fleets, while leaving enough octopus in the sea to be enjoyed by the hundreds of divers and snorkellers who loved watching these amazing creatures last year.

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Bryce Stewart receives funding from DEFRA, Plymouth City Council, Devon County Council and the Crown Estate (OWEC Programme)

Emma Sheehan receives funding from DEFRA and Natural England.

Tim Smyth receives funding from the Natural Environment Research Council through their National Capability funded project AtlantiS NE/Y005589/1

– ref. Octopus numbers exploded around the UK’s south-west coast in 2025 – a new report explores this rare phenomenon – https://theconversation.com/octopus-numbers-exploded-around-the-uks-south-west-coast-in-2025-a-new-report-explores-this-rare-phenomenon-269723

Source: The Conversation – UK – By Laura Elin Pigott, Senior Lecturer in Neurosciences and Neurorehabilitation, Course Leader in the College of Health and Life Sciences, London South Bank University

For much of the 20th century, scientists believed that the adult human brain was largely fixed. According to this view, the brain developed during childhood, settled into a stable form in early adulthood, and then resisted meaningful change for the rest of life.

Today, the concept of neuroplasticity, the brain’s ability to change its structure and function in response to experience, is a central principle of brain science. The brain can change throughout life, but not without limits, not instantly and not effortlessly.

Neuroplasticity therefore reframes the brain as neither rigid nor infinitely malleable, but as a living system shaped by experience, effort and time.

The roots of neuroplasticity can be traced to the mid-20th century. In 1949, psychologist Donald Hebb proposed that connections between neurons, the brain’s nerve cells, become stronger when they are repeatedly activated together.

This principle later became known as “Hebbian learning”. At the time, Hebb’s idea was considered relevant mainly to childhood development. Adult brains were still thought to be relatively unchangeable.

That assumption has since been overturned. From the late 20th century onward, studies showed that adult brains can reorganise in response to learning, changes in sensory input, or physical injury. Sensory changes include alterations in vision, hearing or touch due to training, loss of input or environmental change.

More recently, advances in brain imaging have allowed researchers to observe these changes directly in living people. These studies show that learning alters patterns of brain activity and connectivity across the lifespan.

Neuroplasticity is now understood not as a rare exception, but as a basic property of the nervous system. It operates continuously, within biological limits shaped by age, genetics, prior experience and overall brain health.

How the brain changes

Neuroplasticity involves changes in how existing brain cells communicate with one another.

When you learn a new skill, specific synapses, the tiny junctions where neurons pass signals to each other, become stronger and more efficient. Neural networks, which are groups of neurons that work together, become better organised. Communication between brain regions involved in that skill improves.

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Read more:
No, your brain doesn’t suddenly ‘fully develop’ at 25. Here’s what the neuroscience actually shows

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At the cellular level, plasticity involves changes in synaptic structure, the release of chemical messengers called neurotransmitters, and the sensitivity of receptors that receive those signals. So, it changes how neurons communicate with each other.

In a few areas of the adult brain, particularly the hippocampus, which plays a key role in memory, limited adult neurogenesis, the creation of new neurons, also occurs. Although influenced by factors such as stress, sleep and physical activity, its significance in humans is still debated.

Crucially, neuroplasticity is experience-dependent. The brain changes most reliably in response to repeated, focused and meaningful engagement that requires attention, effort and feedback. Passive exposure to information has far less impact.

What strengthens and weakens plasticity

Over the past decade, research has identified several factors that strongly influence how plastic the brain can be.

1. Practice and challenge are essential.

Repeatedly engaging in tasks that stretch your abilities leads to changes in both brain activity and brain structure, even in older adults.

2. Physical exercise is one of the most powerful enhancers of plasticity.

Aerobic activity increases levels of brain-derived neurotrophic factor, or BDNF, which supports neuron survival and strengthens synaptic connections. Regular exercise is consistently linked to better learning, memory and overall brain health.

3. Sleep plays a critical role in consolidating brain changes.

During deep sleep, important neural connections are strengthened while less useful ones are weakened, supporting learning and emotional regulation, as shown in neuroscience research.

4. Chronic stress can seriously impair plasticity.

Long-term exposure to stress hormones is associated with reduced complexity of neural connections in memory-related brain regions and heightened sensitivity in threat-processing systems, undermining learning and flexibility.

When plasticity works against us

One of the most important and often misunderstood aspects of neuroplasticity is that it is value-neutral. The brain adapts to repeated experiences whether those experiences are helpful or harmful.

This helps explain why conditions such as chronic pain, anxiety disorders and addiction can become self-reinforcing. Through repeated patterns of thought, feeling or behaviour, the brain learns responses that are unhelpful but deeply ingrained, a process known as maladaptive plasticity.

The hopeful side of this insight is that plasticity can also be deliberately directed toward recovery. Psychological therapies such as cognitive behavioural therapy are associated with measurable changes in brain activity and connectivity, particularly in networks involved in emotional regulation. Rehabilitation after stroke or brain injury relies on the same principles, using repeated, task-specific practice to compensate for damaged areas.

Clearing up common myths

Perhaps the most persistent myth is that neuroplasticity means the brain can change rapidly or without limits. In reality, meaningful neural change takes time, repetition and sustained effort, within biological constraints.

Another misconception is that plasticity disappears after childhood. While children’s brains are especially flexible, strong evidence shows that plasticity continues throughout adulthood and into older age.

Claims that brief brain-training programmes dramatically increase intelligence or prevent dementia are not supported by solid scientific evidence. The issue is that meaningful brain change happens most when learning is challenging, varied, and connected to real life.

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Read more:
Brain-training games remain unproven, but research shows what sorts of activities do benefit cognitive functioning

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Activities such as learning a language, exercising regularly, playing a musical instrument, or engaging in complex social interaction are far more effective at strengthening the brain than tapping through app-based puzzles.

In short, brain-training games can be fun and mildly useful, but they train you to play games well, not to think better overall.

Our understanding of neuroplasticity has come a long way since Hebb’s early ideas. What was once thought impossible is now accepted scientific fact. Embracing neuroplasticity means recognising that brains can change, while remaining realistic about how slowly and selectively that change occurs.

More than a century ago, Spanish neuroscientist Santiago Ramón y Cajal wrote that every person can become the sculptor of their own brain. Modern science shows that this sculpting never truly ends. It simply requires effort, patience and persistence.

Siobhan Mc lernon receives funding from The Burdett trust for Nursing

Laura Elin Pigott 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. Scientists once thought the brain couldn’t be changed. Now we know different – https://theconversation.com/scientists-once-thought-the-brain-couldnt-be-changed-now-we-know-different-271252

Source: The Conversation – UK – By Mete Sefa Uysal, Lecturer in Social & Political Psychology, University of Exeter

When people encounter racism or discrimination, they don’t all respond in the same way. Some calmly challenge the remark, some file a complaint, others confront the offender aggressively – and many say nothing at all.

A common assumption is that speaking up against discrimination is a matter of personal courage, political ideology or education. But my recent research suggests that people’s cultural values, shaped by their backgrounds and life experiences, strongly influence how they confront discrimination.

Confrontation comes in very different forms. Some choose to confront non-aggressively (such as calmly pointing out prejudice, explaining why it is offensive or sharing how it impacts them emotionally). Others prefer relatively more aggressive confrontation (such as shouting back, threatening or physical retaliation). These responses carry different risks and consequences, both for the person confronting and for wider social relations.

My recent study with colleagues Thomas Kessler and Ayşe K. Uskul looked at how people’s cultural views of honour affected how they might respond to an insult or discrimination.

Honour is often misunderstood as a personal trait or a relic of “traditional” cultures. In psychology, honour is better understood as a cultural system that develops when people cannot rely on institutions – such as courts or police – to protect them from harm or injustice.

Honour cultures, common in Latin America, north Africa, south and west Asia and the southern US, often developed under harsh historical, social and ecological conditions, for example, scarce resources unprotected by central authorities.

In such contexts, reputation matters. Maintaining honour requires projecting a reputation for toughness. It means signalling a readiness to retaliate against perceived threats or insults to protect oneself and one’s family.

Being seen as weak or passive can invite further mistreatment, so individuals and groups learn to defend their dignity themselves. Honour codes travel with people through migration, continuing to shape how they interpret threats, insults and unfair treatment in new social environments.

The role of honour

Our study sought to understand how internalised honour codes shape responses to discrimination. Specifically, we looked at two communities: south and west Asians in the UK and Turkish migrants in Germany.

People in these communities may have grown up in an honour culture, where personal retaliation against insults is expected. Or, they may have learned these codes from parents and grandparents, while living in countries where such codes are not widespread.

Our findings show that honour codes play a central role in how people say they would confront discrimination. We asked participants a series of questions about their views on honour, as well as their experiences of discrimination. We then asked them to rate the different confrontation styles that they might use when someone discriminates against them based on their ethnic or cultural background.

We found that broadly, people who experienced discrimination more frequently said they were more likely to confront it. But the style of confrontation they chose depended strongly on their cultural values.

A key finding concerned collective honour: the belief that you have a responsibility to defend the dignity of your ethnic or cultural group. Participants who strongly endorsed collective honour reported they were more likely to confront prejudice in any form, whether calmly or aggressively. For them, remaining silent felt like allowing an insult to stand.

In contrast to those who view honour as a collective quality, there are also those who view honour as more of an individual, internalised quality. This can manifest in how people rate the importance of family reputation, and their readiness for retaliation against insults.

People who emphasised family reputation values – concern with maintaining respectability and avoiding shame – said they were more likely to confront discrimination in non-aggressive ways. They also reported being less likely to respond aggressively. Maintaining dignity, for them, meant self-control.

Those who strongly endorsed retaliation values – belief that failing to respond to insults signals weakness and dishonour – were more likely to confront prejudice aggressively and less likely to use calmer strategies. In other words, honour does not push people uniformly toward violence or to remain silent. Different honour codes lead to very different ways of speaking up.

Interestingly, broader structural factors — such as financial insecurity or distrust in the police and authorities — played a smaller role than expected in how people responded to discrimination. What mattered most was how often people actually experienced discrimination.

Repeated exposure to discrimination increased the likelihood of aggressive confrontation, especially among those who endorsed retaliation norms. This suggests that speaking up is shaped less by abstract perceptions of injustice and more by life experiences.

Why this matters

Political rhetoric around immigration has contributed to a broader climate of hostility and suspicion of some communities. This is evident in the waves of anti-immigration protests the UK has seen in recent years, and their effects on communities. According to Home Office data released in late 2025, police recorded 10,097 racially or religiously aggravated offences in August 2024 alone.

Against this backdrop, those who speak up — whether in calm advocacy or in heated confrontation — risk being judged against a narrow standard of “civility” that disregards the personal and cultural experiences that shape their responses.

For some people, walking away preserves dignity. For others, it undermines it. This does not mean all confrontational responses are equally effective or desirable.

But it does mean that judging these responses without understanding their cultural roots risks blaming individuals for navigating systems that were never designed to protect them. If we want more constructive conversations about discrimination and how we speak up against it, our research can offer a place to start.

Mete Sefa Uysal 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. Why some people speak up against prejudice, while others do not – https://theconversation.com/why-some-people-speak-up-against-prejudice-while-others-do-not-272867

Source: The Conversation – UK – By Paige dePolo, Lecturer in Vertebrate Biology, Research Centre in Evolutionary Anthropology and Palaeoecology, Liverpool John Moores University

When you hear the word “dinosaur”, the first thing that might spring to mind is a hulking skeleton like Sue the T rex in Chicago’s Field Museum or Sophie the Stegosaurus at the Natural History Museum in London. Dinosaur skeletons give us striking evidence of what these ancient animals looked like, from the plates and spikes on stegosaurs like Sophie to the long-necked, airplane-sized bodies of titanosaurs.

However, despite their iconic status as museum centerpieces, skeletons are not the most common type of dinosaur fossil known. That prize goes to dinosaur footprints.

The abundance of dinosaur footprints is intuitive. Each dinosaur could only leave one skeleton – but on any single day of its life, it could make thousands of footprints. So, even if only a tiny fraction were fossilised, we could expect to see many more of them in the fossil record.

Dinosaur footprints form in environments where the ground is soft enough to leave an impression, but still cohesive enough so that the shape of the track does not collapse. We find dinosaur footprints in Mesozoic (252-66 million years old) sedimentary rocks all around the world.

Dinosaurs left their mark along coastlines in the UK, ranging from sauropod tracks on the Isle of Skye to Iguanodon tracks on the Isle of Wight. Prosauropod tracks adorn Italian mountainsides. In Bolivia, the largest dinosaur tracksite currently known consists of upwards of 16,000 theropod tracks plus a variety of swimming tracks.

Although dinosaur footprints are abundant, they are challenging fossils to study and identify. Our team, led by Gregor Hartmann at Helmholtz-Zentrum Berlin, has combined AI techniques from photon science with palaeontology in a novel attempt to address this issue.

The footprint puzzle

Dinosaur footprints are not perfect snapshots of the feet that made them. They reflect the shape of the foot, how the dinosaur was moving, and how soft or hard the ground was at the time.

Millions and millions of years of geological history have passed during which the original surface on which the dinosaur walked was buried, transformed to rock, and exposed again. Working on dinosaur footprints necessitates taking all of those factors into account when studying their shapes.

Another challenge arises when trying to determine what dinosaur made which footprints. In particular, tridactyl (three-toed) dinosaur footprints are very tricky to identify, because a wide variety of different dinosaurs have three functional toes on their hind foot. Dinosaurs as different as Megalosaurus and Iguanodon, Edmontosaurus and Albertosaurus, and Tyrannosaurus and Hadrosaurus all have three toes. These dinosaurs fall into two main groups: meat-eating theropods and plant-eating ornithopods.

When we take into account all of the different factors that contribute to the shape of a dinosaur footprint, it becomes extremely challenging to determine whether some three-toed footprints come from theropod or ornithopod dinosaurs.

An unlikely collaboration

Every fossil is a miracle. It takes the perfect combination of circumstances for a fossil to form, be preserved through millions of years, and be found and recognised by human eyes. Our collaboration arose in a similarly serendipitous way.

A physicist and data scientist, Hartmann was reading The Rise and the Fall of the Dinosaurs to his young son Julius, who was very interested in dinosaurs. As he read, Hartmann wondered if the AI methods he was using in photon science could be applied to paleontological questions. So he reached out to the book’s author, Steve Brusatte.

This led to the idea of developing an unsupervised neural network for studying dinosaur footprints. We built our training data from around 2,000 real footprints, then added millions of augmented variations to that initial dataset through strategies like displacing the edges of the footprints by a few pixels. Optimising the network took us over a year.

The key step forward for this network was its unsupervised nature. Only the outlines of the footprints were input, with no additional information about what dinosaurs might have made them. Then the network was allowed to independently discover how the different shapes varied.

This approach meant we avoided human bias in footprint identifications at the training stage. In the end, our model identified eight core axes of footprint variation, including digit spread and heel position.

When we compared the footprint groupings with expert classifications afterwards, we found 80-93% agreement overall. Thus, we could be reasonably confident the model provides a data-driven way to test the identity of particular footprints. Our findings have just been published in the scientific journal PNAS.

However, we wanted to make the network accessible to everyone, not just scientific specialists. That desire gave rise to DinoTracker, a free public app that can enable anyone to upload a picture of a dinosaur’s footprint, sketch its outline, and get instant analysis of what footprints their track is most similar to. The app can be downloaded onto a desktop from Github with the support of this installation guide.

This app certainly isn’t the end of the story when it comes to puzzling over the mysteries of dinosaur footprints. It’s a useful research resource for figuring out what tracks any footprint is most similar to in terms of shape, and what features are driving that similarity.

More excitingly, it’s a tool for curious children like Julius to take outside when they are exploring. Anyone can snap a photo, draw an outline and compare their discoveries to other dinosaur footprints.

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This article includes a reference to a book included for editorial reasons, and a link to bookshop.org. If you click that link and go on to buy something from bookshop.org, The Conversation UK may earn a commission.

Paige dePolo 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. Identifying dinosaurs from their footprints is difficult – but AI can help – https://theconversation.com/identifying-dinosaurs-from-their-footprints-is-difficult-but-ai-can-help-274386

Source: The Conversation – UK – By David Hastings Dunn, Professor of International Politics in the Department of Political Science and International Studies, University of Birmingham

One year into Donald Trump’s second term it is clear that US foreign policy has taken a radical turn from anything seen in the previous 80 years. After the second world war, a system of treaties and alliances saw the US commit to upholding international institutions, rules and laws, as well as promote global prosperity through free trade and market access.

But these things are all antithetical to Trump’s foreign policy vision. Trump appears committed to the abandonment of this longstanding foreign policy stance and to the abdication of his country’s leadership role at the top of the international system. In fact, he seems intent on destroying many of the tenets and institutions of this system and replacing it with an altogether different vision of international relations.

With a background in real estate, Trump sees the world through a transactional lens. He appears to see alliances as a financial burden and a source of security vulnerability, and considers an open trading system to be unfair to the US as the world’s largest market. Trump also seems to find dealing with democracies more burdensome than bargaining with autocratic rulers. For him, the global system of liberal rules and institutions simply acts to prevent the US from using its power to its full advantage.

Trump has always thought this way. Before entering politics, he was a vocal opponent of the 1992 North American Free Trade Area, the World Trade Organization, the Trans-Pacific Partnership and US military intervention in Iraq and Afghanistan. What has changed is his ability to act. In Trump’s first term, establishment advisers largely put a crimp on his more aggressive instincts. Now he feels unconstrained.

Trump’s world view

In contrast to the post-war project, Trump’s world vision is a zero-sum game that sees trade, wealth and security as commodities to be hoarded and not shared around. He has demonstrated this by imposing sweeping trade tariffs and threatening to not defend Washington’s Nato allies unless they pay more for their own defence.

This is a fundamental challenge for leaders elsewhere in the west. Central to the notion of the west is that it constitutes a common identity of shared material interest, liberal values and – to a greater or lesser extent – shared cultural and ancestral heritage.

This shared western sense of self was central to the credibility of nuclear deterrence at the heart of its cold war strategy and the reason for Nato’s establishment. Because the nations that made up the west considered themselves to be as one, the notion that an attack on one was an attack on all was seen as credible.

Trump’s portrayal of western allies as free-riding trade rivals who exploit access to the US market while not paying for their own defence shatters this carefully constructed sense of collective identity and the credibility of the security commitment on which it rests. However, this is of little concern to an administration that shows little interest is defending common interests or alliances.

This is not the only gripe Trump has with Europe. For Trump and his advisers, Europe looks increasingly different to what they see as being the defining characteristics of the US. The US they imagine is in contrast to the liberal republicanism of the nation’s founding fathers and instead draws on the alternative Christian nationalist tradition in American political thought.

In this view, American identity is one that is white and Christian. This partly explains the anti-immigration policies of the Trump administration and, in particular, why its 2025 national security strategy lists the end of “mass migration” as a major policy priority. It is also why Trump and his senior aides are so critical of traditional US allies in Europe.

The national security strategy makes much of the threat of “civilizational erasure” in Europe, arguing that “it is more than plausible that within a few decades at the latest, certain Nato members will become majority non-European”. By this, it appears the Trump administration means Europe will have become majority non-white and non-Christian.

This stance was reflected by the US vice-president, J.D. Vance, in February 2025 when he told the Munich security conference that he was more worried about “threats from within Europe” than those posed by Russia or China. For Vance and his allies, support for right-wing parties that oppose immigration and seek to limit the power and influence of the EU is central to the adminstration’s foreign policy.

Trump’s foreign policy poses considerable challenges for those who want to protect a world order that was built by a very different US decades ago. This conflict of ideas appears to have come to a head at the recent World Economic Forum in Davos, where the leaders of many countries committed to that world order and signalled their willingness to defend their case.

In doing so they have demonstrated that in dealing with a transactional Trump, sometimes their best response is to show him that there are certain red lines that cannot be crossed.

David Hastings Dunn has previously received funding from the ESRC, the Gerda Henkel Foundation, the Open Democracy Foundation and has previously been both a NATO and a Fulbright Fellow.

– ref. US foreign policy has taken a radical turn in Trump’s first year back in office – https://theconversation.com/us-foreign-policy-has-taken-a-radical-turn-in-trumps-first-year-back-in-office-273917

Source: The Conversation – UK – By Katie Edwards, Commissioning Editor, Health + Medicine and Host of Strange Health podcast, The Conversation

The human body, it turns out, is surprisingly good at making stone.

Give it enough time and the right conditions and it will go about crystallising minerals, hardening secretions and, in rare cases, turning tragedy into rock. Gallstones. Kidney stones. Tonsil stones. Salivary stones. And, in one of the strangest and saddest corners of medical history, stone babies.

In the second episode of The Conversation’s Strange Health podcast, we take a tour through the stony side of human anatomy and ask why this keeps happening, where these stones form and which ones you actually need to worry about.

Strange Health explores the weird, surprising and sometimes alarming things our bodies do. Each episode takes a bodily mystery or viral health claim and traces it back to anatomy, chemistry and evidence, drawing on researchers with first-hand experience of these processes. Some discoveries are not ideal mealtime material.

This episode’s guide is Adam Taylor, professor of anatomy at Lancaster University and long-time contributor to The Conversation. Taylor has spent years studying stones in both everyday and extraordinary contexts, including a rare genetic condition called alkaptonuria. In people with this condition, the body cannot properly break down certain proteins, leading to blackened cartilage, dark urine and an unusually high risk of stone formation throughout the body. It is exactly as unsettling as it sounds.

Stones, Taylor explains, form when substances that normally stay dissolved stop behaving themselves. Calcium, phosphate, uric acid and one of the building blocks of protein called cysteine can all crystallise if conditions are right. Once a few molecules stick, more follow. The process snowballs. Over time, a stone appears.

Kidney stones and gallstones are the most familiar examples, and among the most painful. Their jagged crystal edges scrape delicate tissues, trigger spasms and cause bleeding as the body desperately tries to force them through narrow ducts never designed for sharp objects. Larger stones can block urine flow entirely, damaging the kidneys and, if left untreated, causing serious harm.

Smaller stones can form elsewhere. Tonsil stones develop when food debris, bacteria and dead cells collect in the crevices of the tonsils and harden. Salivary stones can form when ducts become blocked by bacteria or foreign material, sometimes something as mundane as a stray toothbrush bristle. These stones are rarely dangerous, but they are often unpleasant, painful and, judging by social media, irresistibly watchable when removed.

Then there are stone babies, or lithopedions. In extremely rare cases, a pregnancy that cannot continue is not expelled from the body. Instead, the immune system encases the remains in calcium, effectively mummifying them to prevent infection. Some have been discovered decades later, only after death.

What unites all of these stones is not toxins or detoxing, but chemistry and fluid balance, and sometimes bad luck. Taylor stresses that dehydration is one of the biggest risk factors. When fluids slow down, materials that are normally carried in fluid begin to solidify. Stones follow.

Listen to Strange Health to understanding why solid things form inside something that is mostly water, and why some stones are medical emergencies while others are just deeply, memorably gross. You have been warned about watching while eating.

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Strange Health is hosted by Katie Edwards and Dan Baumgardt. The executive producer is Gemma Ware, with video and sound editing for this episode by Sikander Khan. Artwork by Alice Mason.

In this episode, Dan and Katie talk about a social media clip from tonsilstonessss on TikTok.

Listen to Strange Health via any of the apps listed above, download it directly via our RSS feed or find out how else to listen here. A transcript is available via the Apple Podcasts or Spotify apps.

Katie Edwards works for The Conversation.

Adam Taylor and Dan Baumgart 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. Tonsils, kidneys and gall: where and why your body makes stones – https://theconversation.com/tonsils-kidneys-and-gall-where-and-why-your-body-makes-stones-274192

Source: The Conversation – UK – By Pankhuri Agarwal, Leverhulme Early Career Research Fellow, University of Bath; King’s College London

A new trade agreement between India and the UK is due to come into force this year.
The deal is expected to completely remove tariffs from nearly 99% of Indian goods, including clothing and footwear, that are headed for the UK.

In both countries, this has been widely celebrated as a win for economic growth and competitiveness. And for Indian garment workers in particular, the trade agreement carries real promise.

This is because in recent years, clothing exports from India have declined sharply as well-known fashion brands moved production to places like Morocco and Turkey, which were cheaper.

India’s internal migrant workers (those who move from one region of the country to another looking for work) have been hit hardest, often waiting outside factories for days for the chance of a single shift of insecure work.

Against this backdrop, more opportunities for steadier employment and a more competitive sector under the new trade agreement looks like a positive outcome. But free trade agreements are not merely economic instruments – they shape labour markets and working conditions along global supply chains.

So, the critical question about this trade deal is not whether it will generate employment in India – it almost certainly will – but what kind of employment it will create.

Few sectors illustrate this tension more clearly than the manufacture of clothing. As one of India’s biggest exports, its garments sector is expected to be one of the primary beneficiaries of the trade deal.

But it is also among the country’s most labour-intensive and exploitative industries. From denim mills in Karnataka to knitwear and spinning hubs in Tamil Nadu, millions of Indian workers receive low wages and limited job security.

Research also shows that gender and caste-based exploitation is widespread.

So, if the trade deal goes ahead without addressing these issues, it risks perpetuating a familiar cycle where we see more orders and more jobs, but the same patterns of unfair wages, insecurity and – in some cases – forced labour.

Marginalised

For women workers, who form the backbone of garment production in India, these vulnerabilities are even sharper.

Gender-based violence, harassment and unsafe working conditions have been documented repeatedly across India’s export-oriented factories. Regimes which bound young women to factories under the promise of future benefits that often never materialised show how caste- and gender-based discrimination have long been embedded within the sector.

Even in factories that formally comply with labour laws, wages that meet basic living costs remain rare. Many workers earn wages which are not enough to pay for housing, food, healthcare and education, pushing families into debt as suppliers absorb price pressures imposed by global brands.

On the plus side, the India-UK agreement does not entirely sidestep these issues. There is a chapter which outlines commitments to the elimination of forced labour and discrimination.

But these provisions are mostly framed as guidance rather than enforceable obligation. They rely on cooperation and voluntary commitments, instead of binding standards.

While this approach is common in trade agreements, it limits this deal’s capacity to drive meaningful change. But perhaps even more striking is what has been left out.

Despite the role India’s social stratification system, known as caste, plays in shaping labour markets in India, it is entirely absent from the text of the agreement.

Yet caste determines who enters garment work and who performs the most hazardous and lowest-paid tasks. A significant proportion of India’s garment workforce comes from marginalised caste communities with limited bargaining power and few alternatives.

By addressing labour standards without acknowledging caste, the free trade agreement falls short. It could have required the monitoring of issues concerning caste and gender, and demanded grievance mechanisms and transparency measures that account for social hierarchies.

Instead, a familiar gap remains between commitments to “decent work” on paper and the reality which exists on factory floors.

Missed opportunity

If the India-UK deal is to be more than a tariff-cutting exercise, protections around caste and gender must be central to its implementation.

The deal is rightly being celebrated in both countries as an economic milestone. For the UK, it promises more resilient supply chains and cheaper imports. For India, it offers renewed export growth and the prospect of some more stable employment.

But the agreement’s long-term legitimacy will rest on whether it also delivers social justice.

India can use the deal to strengthen labour protections and ensure growth does not come at the cost of dignity and safety. The UK, as a major consumer market, can use its leverage to insist on enforceable standards for fair wages and decent work.

For trade deals do not simply move goods across borders – they shape the conditions under which those goods are produced.

Pankhuri Agarwal receives funding from the Leverhulme Trust as an Early Career Research Fellow.

– ref. The India-UK trade deal is a prime opportunity to protect some of the world’s most vulnerable workers – https://theconversation.com/the-india-uk-trade-deal-is-a-prime-opportunity-to-protect-some-of-the-worlds-most-vulnerable-workers-274055

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

Source: The Conversation – UK – By Tim Heppell, Associate Professor of British Politics, University of Leeds

The Labour party’s National Executive Committee (NEC) has voted to block Andy Burnham from seeking selection for the vacant Gorton and Denton parliamentary seat. The move and its fallout have exposed fault lines within the Labour party that go beyond a single byelection.

What might otherwise have been a routine internal procedural matter has instead become a revealing episode about authority, legitimacy and control inside the party – and how Keir Starmer understands both internal democracy and political risk.

The vacancy itself arose from the resignation of the Labour MP, Andrew Gwynne. A byelection must now be held in a constituency long assumed to be safely Labour. The party won 50% of the vote at the last general election with Reform second on 14%. Recent electoral volatility, however, has made even such strongholds less predictable.

This context matters. Byelections are no longer cost-free exercises in party management. They can become national political moments, particularly when they intersect with questions of leadership and direction.

Burnham’s interest in returning to Westminster must be understood against this backdrop. Since leaving parliament and becoming mayor of Greater Manchester in 2017, Burnham has established himself as one of Labour’s most recognisable and electorally successful figures.

His mayoralty has given him a distinct political identity, rooted in devolution, public services and a forthright northern voice. His approach has often contrasted with the more centralised and cautious tone of Starmer’s leadership since 2020.

And with Burnham consistently cited as a contender to replace Starmer, it’s difficult to separate his desire to return to parliament from his desire for the leadership. A return to Westminster could provide Burnham with influence, visibility and long-term options that a regional office, however powerful, cannot fully provide.

It is precisely because Burnham occupies such a prominent executive role that he needed the NEC’s approval to run. Labour’s rules are clear: directly elected mayors must seek permission before becoming parliamentary candidates. This is largely to prevent the disruption and expense of triggering further elections. Burnham would have to be replaced as mayor and a contest would be costly.

On the surface, therefore, the NEC’s involvement was procedurally acceptable. What transformed it into a political controversy was how its decision to block him is being interpreted.

Internal democracy vs central control

Supporters of Burnham argued that the case for allowing him onto the shortlist was strong. At a basic level, they maintained that local party members should have been trusted to decide whether he was the right candidate. This argument drew on long-standing Labour principles about internal democracy and local autonomy.

Burnham’s profile, record of winning elections as mayor and roots in Greater Manchester were seen as assets that could only strengthen Labour’s chances of holding the seat. At a potentially awkward moment in the electoral cycle and with high-profile figures rumoured to be thinking of running for other parties, this is by no means a given.

Beyond electoral calculation, there was also a symbolic dimension. Allowing a figure of his stature to compete would have signalled confidence within the party. It would have shown a willingness to tolerate pluralism and ambition rather than to manage it out of existence.

For some senior figures, including the deputy leader, Lucy Powell (no ally of Starmer) the issue was not whether Burnham should automatically be selected, but whether it was right for the national party to remove him from the contest before it began.

The arguments against Burnham’s candidacy focused on the costs and risks associated with triggering a mayoral election. There was also a concern about distraction. The leadership has been keen to project stability and discipline, and the return of a high-profile figure with an independent political base could complicate this.

Yet it is difficult to ignore the political subtext. Burnham’s record of public disagreement with elements of the leadership’s strategy marked him out as a potential alternative focus of authority within the party.

Blocking his return to parliament therefore carries the appearance, whether intended or not, of pre-emptive containment. For critics, this reinforces a perception that the NEC is being used not simply as a guardian of rules, but as an instrument of political management.

The committee’s eight-to-one vote against Burnham intensified these concerns. Powell was the only member to vote in Burnham’s favour and the chair, home secretary Shabana Mahmood, abstained.

On one reading, this demonstrated that the leadership’s position commanded overwhelming institutional support. On another, it underlined the marginalisation of dissenting voices, even at the highest levels of the party.

That the only explicit supporter of Burnham was also one of Labour’s most senior elected figures lends the episode a particular symbolic weight. Powell won her position via a membership vote rather than being appointed by Starmer.

What happens next

The broader political ramifications of this situation are complex. In the short term, the decision may suit Starmer. Preventing Burnham from re-entering parliament reduces the likelihood of an alternative leadership figure emerging on the backbenches. It also allows the leadership to maintain tight control over messaging and candidate selection at a moment when it believes discipline is electorally advantageous.

However, the longer-term risks should not be underestimated. The episode feeds into an existing narrative that Labour under Starmer is highly centralised and wary of internal competition. For party members and supporters who value participation and openness, this risks alienation.

There is also an electoral gamble in blocking Burnham. Should Labour struggle in or even lose the Gorton and Denton byelection, the decision to exclude Burnham will be retrospectively scrutinised as a missed opportunity. Conversely, even a comfortable victory will not entirely erase the impression that the party prioritised internal control over open debate.

Ultimately, the Burnham affair illuminates a central tension within Labour: the balance between authority and legitimacy. The NEC may have acted within its formal powers, but legitimacy in politics is never solely procedural. It is also relational, shaped by how decisions are perceived by members, voters and the wider public.

Tim Heppell 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. Labour blocks Andy Burnham from standing for parliament: how it happened and why – https://theconversation.com/labour-blocks-andy-burnham-from-standing-for-parliament-how-it-happened-and-why-274309