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April 2, 2026

AI’s fluency in other languages hides a Western worldview that can mislead users − a scholar of Indonesian society explains

Source: The Conversation – USA (3) – By Gareth Barkin, Professor of Anthropology and Asian Studies, University of Puget Sound

AI models derive their assumptions from English-language sources based in the United States. Weiquan Lin/Moment via Getty Images

A friend in Indonesia recently told me about a conversation he had with ChatGPT. He had typed a question in Indonesian – Bahasa Indonesia – about how to handle a difficult family dispute. The chatbot responded fluently, in perfect Indonesian, with advice about communication strategies and conflict resolution. The grammar was flawless. The tone was appropriate. And yet something felt off.

What the AI offered was advice rooted in American cultural assumptions: prioritize your own preferences, communicate directly, and if family members don’t respect your boundaries, consider cutting them off.

The response was in Indonesian but shaped by values that centered individual autonomy over the consensus-building, social harmony and collective family dynamics that tend to matter more in Indonesian social life.

My friend was skeptical enough to notice the mismatch and mention it to me. Many users might not. That is what prompted my research, published in the International Review of Modern Sociology, into a pattern I found across major AI systems: Even when they were fluent in several languages, the language models retained their Western worldview. I call this “epistemological persistence.”

Fluency is not the same as understanding

I have studied Indonesian society, media and culture for more than 30 years. That gives me a particular vantage point on a problem that reaches well beyond Indonesia: large language models – LLMs – like ChatGPT, Claude and Gemini can now speak dozens of languages with remarkable fluency. That fluency creates the impression that AI understands local cultures.

Producing grammatically correct Indonesian, Arabic, Swahili or Hindi, however, does not change the underlying worldview through which these systems reason. It does not alter how they think about people, relationships, responsibility or what counts as a good outcome.

Those assumptions are shaped by training data drawn predominantly from English-language sources based in the United States. Meta’s open-weight model LLaMA 2 was trained on approximately 89.7% English-language text; LLaMA 3 includes only about 5% non-English data. Major commercial models don’t publish equivalent breakdowns but draw heavily on the same sources. Arabic, the fifth-most-spoken language globally, accounts for under 1% of content in large training datasets. Languages with tens of millions of speakers, including Bengali and Hausa, barely appear.

Beneath the surface of these multilingual conversations, English functions as a hidden intermediary. A study by researchers at the University of Oxford found that LLMs routinely conduct their core reasoning in English, even when prompted in other languages. They translate the output at the final stage. A user receives flawless text in their preferred language, but the underlying logic originates elsewhere.

What the data shows

To examine how this plays out in practice, I ran experiments with ChatGPT, Claude and Gemini. I asked questions in both English and Indonesian about concepts such as education, responsibility, well-being and several Indonesian terms that resist direct translation into English. These included terms such as “gotong royong,” which describes a tradition of communal mutual assistance.

Then I asked questions about education in both languages, using the word “pendidikan” in Indonesian. The answers were consistently centered on individual development, personal autonomy, critical thinking and preparation for the labor market.

What largely disappeared were the dimensions of pendidikan that Indonesian educational traditions have historically emphasized. In Indonesia education has long been focused on ethical discipline. Scholars of Indonesian education such as Christopher Bjork and Robert Hefner have documented how distinct these traditions are from models that treat education primarily as a path to individual advancement and career preparation, which is the lens through which the AI tools viewed education.

The Indonesian concept of “malu” offers a starker example. Often translated as “shame” or “embarrassment,” malu has been analyzed by anthropologists Clifford Geertz and Tom Boellstorff as something closer to a shared social awareness.

A person might feel malu when speaking out of turn in front of elders, or when a family member’s behavior reflects poorly on the household. It regulates conduct and signals awareness of one’s position within a web of relationships. It is cultivated, not merely felt. It is a form of relational awareness rather than a private psychological event.

When asked directly to define malu, the models acknowledged its social dimensions. In scenario-based questions that simply used the word without asking for a definition, however, all three fell back on the English translation of shame, consistently framing it as an individual emotional experience.

One representative response framed malu as a normal emotional reaction to be managed through self-reflection and confidence-building – a personal psychological problem rather than a social one. The relational dimensions of the concept disappeared entirely, replaced by the language of individual emotional regulation.

A distinctly American worldview travels inside the translation, largely unannounced.

Why this probably won’t change soon

A woman wearing a white jacket points to a programming screen while other members of the team look on. — AI companies rely on translations, as region-specific models would be prohibitively expensive.
Cravetiger/Moment via Getty images

Translation is far cheaper: Train one model on the vast English-language web, then use multilingual output capabilities to serve global markets. As media scholar Safiya Umoja Noble argues about algorithmic systems more broadly, what looks like a technical outcome is actually a structural one, shaped by who has the wealth and infrastructure to build these systems.

The embedded worldview isn’t a mistake; it’s what happens when knowledge production is profit-seeking.

The main exceptions are Chinese models such as DeepSeek and Alibaba’s Qwen. They represent a genuine alternative to the U.S.-dominated pipeline, though research shows they operate through a distinctly Chinese cultural lens. Asked about a workplace disagreement, for instance, they tend to advise silence or indirect phrasing to preserve harmony rather than the direct, private correction that Western models recommend.

Other regional efforts, such as SEA-LION for Southeast Asia and Kan-LLaMA for the Indian language Kannada, use U.S. models as their foundation. They add additional vocabulary and cultural information related to local languages. But the core logic remains tied to the original U.S. training.

Why this matters more than it might seem

One might reasonably ask whether this is simply a limitation users can work around. Decades of media scholarship demonstrate how audiences interpret foreign media through their own cultural frameworks.

For example, anthropologist Brian Larkin documented how viewers in northern Nigeria rework the narratives of Bollywood films to align with local Islamic values. Larkin found that Muslim viewers in Kano reinterpreted Bollywood films through an Islamic moral lens, reading their narratives as reinforcing local values of propriety and ethical conduct. That dynamic depends on encountering media as something with a visible origin. But to do that, you need to know where your media is coming from.

Conversational AI is different. Research at Harvard Business School finds that people increasingly use AI systems for emotional support, advice and companionship. When a culturally specific worldview is delivered through a relationship that feels attentive and empathetic, in your own language, it arrives less as a claim to be evaluated and more as a shared premise within a dialogue. It becomes difficult to notice, and harder to contest.

The concern is that these perspectives become the new normal. Certain ways of reasoning about family life, education and responsibility may come to feel natural and self-evident. Linguistic diversity among AI systems is real and growing. Cultural worldview diversity, however, has not kept pace.

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

– ref. AI’s fluency in other languages hides a Western worldview that can mislead users − a scholar of Indonesian society explains – https://theconversation.com/ais-fluency-in-other-languages-hides-a-western-worldview-that-can-mislead-users-a-scholar-of-indonesian-society-explains-276865

April 2, 2026

Zimbabwe’s push to extend the president’s rule could deepen elite divisions and weaken democracy

Source: The Conversation – Africa (2) – By David B. Moore, Research Associate, Dept of Anthropology & Development Studies and Fellow, Clare Hall, University of Cambridge, University of Johannesburg

Zimbabwe’s ruling party, Zanu-PF, wants to amend the constitution through a bill in parliament. It won’t be that simple, however. Under the constitution, voters must approve such changes through a referendum.

The new bill’s most significant proposals include extending presidential and parliamentary terms by two years. This would allow Zimbabwe’s 83-year-old president, Emmerson Mnangagwa, to remain in power until 2030, ending the hopes of vice-president Constantino Chiwenga reaching the presidency in 2028. Chiwenga, as the head of the armed forces, was the main organiser of the 2017 coup that brought the exiled Mnangagwa to power.

The proposals could also pave the way for further changes that help Zanu-PF realise its long-cherished dream of permanent rule. The amendment proposes ending direct presidential elections. Instead, the president would be chosen by members of parliament. Given that Zanu-PF can, and has, co-opted enough MPs to dominate parliament, this would consolidate executive power within the ruling party.

Other proposed changes include expanding the senate to 90 members and returning the electoral commission to a largely discredited registrar-general who has been accused of bias. The bill also creates a Delimitation Commission that would allow the ruling party to shift constituency boundaries.

I have researched and written on Zimbabwe’s political history and political economy since the early 1980s. In my view, these changes risk weakening already fragile democratic protections in Zimbabwe.

Extending term limits entrenches incumbency. Long-serving president Robert Mugabe established de-facto one-party rule – always contested, but maintained consistently by carefully calibrated doses of coercion, cheating and crafted consensus – in 1987 as he became executive president. This followed the genocidal Gukurahundi massacre of the 1980s when thousands of people were killed as Zimbabwe’s main opposition party was crushed.

The military forced Mugabe to resign in 2017 under “Operation Restore Legacy”. Mugabe was at the time 93. The coup was later legitimised by being given the “military-assisted transition” label.

Zanu-PF veteran Mnangagwa, who had been Mugabe’s recently fired deputy, and since 1978 his key security advisor, took on his mantle. This transition was violently consummated with a contested election in 2018 and vicious quelling of the January 2019 “stay-away” protests calling on the state to improve citizen livelihoods.

These latest proposed amendments – dubbed Agenda 2030 – point to a system where political competition is narrowed and power is more tightly controlled by the ruling party and its leaders.

What it means for Zimbabwe

Removing direct presidential elections reduces voter choice. The weakening of independent institutions – including electoral and judicial bodies – further reduces accountability.

The constitutional amendment proposes that the presidential vote take place in parliament by party-based MPs, who would likely elect one of their own.

However, the generally unpopular ruling party fears going through the necessary referendum to pass such changes. Additionally, 90 days of public consultation on constitutional amendments are needed. The Zanu-PF state has already compressed these to four days at about 65 locations, allowing about an hour each for discussion.

The first meetings were stacked with busloads of Zanu-PF supporters. And as happens during the party’s rallies, there were gifts of bikes and food as the carrots, and intimidation and threats as the sticks. Besides this mix, session chairs ignored opposition efforts to voice their opinions.

By the end of the second day of these meetings, the coalition of the three “defend the constitution” movements opposing Zanu-PF’s proposals boycotted the hearings.

No matter: Zanu-PF will either choose to push a referendum forward (with low participation) or pursue more repressive and/or judicially engineered means to secure the amendments.

What it means for Zanu-PF

The proposed constitutional amendments also have major implications within Zanu-PF itself, particularly for Chiwenga. They would effectively end his chances of becoming president in 2028.

In 2008, highly contested presidential election results forced Mugabe and opposition leader Morgan Tsvangirai to a run-off. As is widely acknowledged, Mnangagwa and Chiwenga – then leading Zimbabwe’s Joint Operations Command – agreed to let Mugabe stay on. They would strike at a more opportune time: Mnangagwa would then lead first, and Chiwenga would take power in the next term.

The severe violence during the run-off led to a transitional inclusive government. This eventually led to the development of the 2013 constitution, which introduced a two-term limit for the presidency.

At a Zanu-PF congress soon after the 2018 election, Mnangagwa announced he’d vie again in 2023.

Now, the proposed extension to 2030 effectively blocks Chiwenga’s path to the presidency. At the very least, those two years would allow Mnangagwa to consolidate his – and his family’s – power. Zanu-PF’s ever present factional tensions will be exacerbated.

As my book Mugabe’s Legacy: Coups, Conspiracies, and the Conceits of Power in Zimbabwe argues, Zanu-PF’s past and present – before, during and after the liberation war – are replete with factional fighting as those near its top seek to entrench one-party rule with its control over the country’s wealth.

What it means for opposition politics

Zimbabwe’s opposition remains fragmented and weakened. The once-powerful Movement for Democratic Change splintered and its closest successor succumbed to Zanu-PF, partly induced by its leader’s megalomania.

After the boycott of the hearings, how will the proposed constitutional amendments be stopped? Resistance to the proposals had created an opportunity for greater opposition unity.

Events such as the October 2025 firebombing of a civil society meeting meant to discuss the amendments foretold the current intimidation.

Will the changes sail through?

Success on the constitutional amendments is not guaranteed. Internal factional tensions, particularly around succession, could complicate the process. Chiwenga is far from the only challenger in Mnangagwa’s sight.

If (when?) the shambolic – yet brutal – ruling party manages to move to a post-Agenda 2030 phase, it may well crash under the weight of its own contradictions. And with it all of Zimbabwe goes.

David B. Moore 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. Zimbabwe’s push to extend the president’s rule could deepen elite divisions and weaken democracy – https://theconversation.com/zimbabwes-push-to-extend-the-presidents-rule-could-deepen-elite-divisions-and-weaken-democracy-279792

April 2, 2026

AI laws overlook environmental damage – here’s what needs to change

Source: The Conversation – UK – By Louise Du Toit, Lecturer in Law, Southampton Law School, University of Southampton

Huge energy-intensive data centres are required to support growing AI demands. Make more Aerials/Shutterstock

More than 200 laws have been developed to regulate AI in more than 100 countries. Many of them focus on issues such as privacy, bias, disinformation, security and cybersecurity rather than the environmental consequences of AI.

AI is an energy-intensive and thirsty industry. It leads to huge greenhouse gas emissions, pollution and loss of nature. These impacts arise partly from the manufacture and use of energy-, carbon- and water-intensive “complex computer chips”, called graphics processing units (GPUs), for the training of AI models as well as increasing e-waste.

My research into the regulatory responses to AI in the EU and the UK highlights how laws often ignore the environmental implications of this big tech. The lack of stringent obligation in AI law and policy is concerning.

There are environmental consequences at all stages of the AI lifecycle. From the manufacture of AI hardware, training of AI models, deployment and use of AI right through to the disposal of AI hardware.

The manufacture of components relies on the extraction of rare earth elements. This can contaminate soil and water, pollute the air and lead to loss of nature and forest habitats. Training AI models is incredibly energy- and water-intensive. A team of researchers estimated in 2025 that training GPT-3 – a large language model released by OpenAI in 2020 – consumed an estimated 700,000 litres of freshwater for electricity generation and cooling of data centres.

Even though AI models are becoming more energy efficient, as models become larger and AI proliferates, overall energy consumption and associated emissions are rising. And the energy consumed in the use of AI, including to generate text or images, vastly outweighs that used during training.

However, it’s difficult to accurately measure the environmental effects of AI, partly due to the lack of transparency of technology companies.

When the EU’s AI Act came into force on August 1 2024, it was the “world’s first comprehensive law” on AI. The AI Act acknowledges some of AI’s environmental consequences. It also requires that “AI systems are developed and used in a sustainable and environmentally friendly manner”.

It outlines that AI providers must disclose information on “known or estimated energy consumption data of the model”. But while promising, this information only needs to be provided when requested by the AI Office, which has been established within the European Commission.

cooling towers/pics in data centre — Industrial cooling towers in every data centre require vast amounts of water.
sutthilak.c10/Shutterstock

Further measures include preparing codes of conduct to assess and minimise “the impact of AI systems on environmental sustainability”. But this is not compulsory. Overall, the AI Act is intentionally anthropocentric. It states that: “AI should be a human-centric technology. It should serve as a tool for people, with the ultimate aim of increasing human wellbeing.”

The UK has no AI-specific legislation. AI is currently only regulated by existing laws. The UK government’s 2023 white paper on AI regulation, which proposes a regulatory framework for AI, doesn’t prioritise sustainability at all. Although the white paper acknowledges that AI can contribute to technologies to respond to climate change, it does not specifically address any environmental risks:

The proposed regulatory framework does not seek to address all of the wider societal and global challenges that may relate to the development or use of AI. This includes issues relating to … sustainability. These are important issues to consider … but they are outside of the scope of our proposals for a new overarching framework for AI regulation.

A transparent future?

More transparency starts with AI developers having to disclose information about how much energy and water is consumed, how much carbon is emitted, the rare earth elements extracted and how much plastic is used during the AI production process.

This data then provides a baseline. Then appropriate targets and limits can be set for energy efficiency, carbon emissions and water use to improve the sustainability of AI.

Several proposals have been made for how reduced carbon emissions and water consumption could practically be achieved, such as training AI models on less carbon-intensive energy grids or in less water-intensive data centres.

Warnings about environmental effects could tell consumers how much carbon dioxide is emitted or water consumed for each query. In addition, an AI labelling system could mirror the EU’s existing energy efficiency labelling schemes, which clearly indicate the energy efficiency of appliances, ranking them from most energy-efficient (dark green) to least energy-efficient (red).

Proposals include an AI “energy star” rating system and a social and environmental certification system. This would help consumers to make informed choices about which AI systems to use or whether AI should be used at all. Tax incentives and funding incentives could also encourage tech firms to make more sustainable choices.

By integrating sustainability into AI laws, through these types of measures, the planet can be somewhat safeguarded alongside AI’s rapid expansion.

Louise Du Toit 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. AI laws overlook environmental damage – here’s what needs to change – https://theconversation.com/ai-laws-overlook-environmental-damage-heres-what-needs-to-change-279047

April 2, 2026

The Samurai Detectives: Volume 2 explores money and kinship in the Edo underworld

Source: The Conversation – UK – By Hui-Ying Kerr, Senior Lecturer in Fashion Communication and Promotion, Nottingham Trent University

At high noon on a scorching summer day, retired samurai Kohei finds the fearsome Kumagoro writhing around a field in agony. The stricken man’s name translates as “demon bear”, and he’s the proprietor of a bar of the same name. Kohei finds him next to a temple famous for a tragic legend of familial loss and despair.

This setting frames the second instalment of The Samurai Detectives, written by Shōtarō Ikenami between 1972 and 1989 and newly translated by Yui Kajita. The novel is steeped in mystery, legend, and the ties and tensions of blood kin, fierce loyalty and pride.

Returning to 18th-century Edo Japan, we leave behind the complex machinations of political assassination plots of the first book. This volume explores the seedier underbelly of the city that became modern-day Tokyo, with a new cast of characters.

Engraving of a demon bear — A depiction of an onikuma (demon bear) by Shunsensai Takehara in the Ehon Hyaku Monogatari (1841).
WikiCommons

In addition to the “demon bear” bar owner, these include an upwardly mobile but corrupt samurai willing to hew down innocent passersby, an aged father-warrior seeking his missing son, a street-vendor looking to “muscle-up”, a beloved merchant’s daughter who keeps disappearing, and a kosamebo (“demon drizzle monk”) who visits in the rain.

In the centre of all this is Kohei, the protagonist samurai-detective, and his son, the upright warrior Daijiro. They’re joined by some familiar faces from their previous adventures.

Life is looking up for the two, with a bit more money and food for Daijiro. But at heart, Kohei is still the wily old samurai whose age belies his mental and physical abilities.

There are also the familiar temptations of cosmopolitan Edo: the easy sex, the allure of money and, underpinning it, the ever-present violence – all of which threaten to topple any one of the characters that succumb to it. Sex and love make for powerful motivators but it’s money that provides the lubricant for the inevitable violence.

Family betrayals and fatherly care

Ultimately, the second Samurai Detective volume is a meditation on the ties of parent-child relationships – and what happens when they go wrong. Satelliting Kohei and Daijiro’s admirable father-son, master-pupil, warrior-comrade dynamic of respect and care are other examples that range from love to despair.

As with the last book, the tension of law verses morality forms the basis of thesde stories. In a city of complex fealty and interconnected relationships, it asks: what does doing the right thing mean?

Social, moral and natural justice all play their part in this complex society – though in a pinch, the rough justice of the warrior code will do. This is clear through the number of arms, legs and noses that go flying during the many sword fights.

Painting of a busy street in Edo Japan. — Suruga Street by Utagawa Hiroshige (1836).
Moma

In this volume, Kohei and Daijiro unravel mysteries shaped by complicated family relationships. At the heart of these stories are contrasts between care, respect, love and loyalty – and on the other side, neglect, abandonment, betrayal and abuse.

The ensuing resolutions use revenge as their motivator. But there are underlying concerns of power, hierarchy and money that structure the intricate society of Edo.

Towards the end of the book, another tragic, unresolved character from the previous volume returns: a figure of doomed, forbidden love. While portrayed as monstrous, we come to understand that worse still was the cruelty of parental abandonment that sets the chain of events in motion. Ultimately, these are also about the abandonment of the samurai code, something that underpins all the stories in this book.

Balancing all this is the fatherly care of Kohei – not only for Daijiro, who he continues to train, but for all the characters who come his way.

From the continuing concern for Mifuyu, the warrior-daughter of the most powerful lord in Edo, to the disappeared son of his own son’s former teacher, Kohei feels the pull of a collective responsibility to the younger ones. Even the lower-status merchant daughters and unagi eel sellers on the street are not below his level of concern.

They fuel an inquisitiveness that leads Kohei to undignified actions, such as hiding in toilets to overhear plots of intrigue – and ultimately investigate.

As a sequel, The Samurai Detectives: The Killer on the Streets does more than paint an ongoing series of mysteries in Edo Japan. It highlights the necessity of respect, love and care in the creation of a stable society.

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.

Hui-Ying Kerr previously received funding from the AHRC for her PhD in History of Design (2010 – 2013), on the 1980s Japanese Bubble Economy.

– ref. The Samurai Detectives: Volume 2 explores money and kinship in the Edo underworld – https://theconversation.com/the-samurai-detectives-volume-2-explores-money-and-kinship-in-the-edo-underworld-279607

April 2, 2026

The world’s supply of helium is being threatened by the Iran war

Source: The Conversation – UK – By Gavin D. J. Harper, Research Fellow, Birmingham Centre for Strategic Elements & Critical Materials, University of Birmingham

The war in the Middle East has disrupted the world’s supply of helium. Qatar produces about a third of global helium, but attacks on its gas infrastructure have forced production to stop.

At the same time, Iran is blocking the Strait of Hormuz, one of the world’s busiest shipping channels, through which Qatar exports both natural gas and helium. Losing 30% of global helium could have major consequences for science, medicine and industry.

Helium is used to cool the superconducting magnets used in MRI (magnetic resonance imaging) scanners, which help diagnose conditions through high-resolution, 3D imaging of human tissues.

Superconducting magnets enable the sustained, intense currents needed for high resolution imaging. A superconductor is a material that conducts electricity with zero resistance (defined as the opposition to current flow in a material).

In order to do this, however, the magnets need to operate at extremely low temperatures.

Helium is the ideal coolant for these magnets because it has the lowest boiling point of any element: -268.9°C. At this temperature or below, helium is liquid and can be used to bathe the magnetic coils used by MRI scanners.

Some particle accelerators, such as the Large Hadron Collider at Cern in Geneva, also use liquid helium to cool their superconducting magnets. These magnets are used to bend and control proton beams.

A versatile element

Helium is used in computer chip production to displace oxygen and moisture within fabrication facilities, where conditions are tightly controlled to avoid contaminating delicate microprocessors.

The element is also used as a coolant during high-temperature stages of chip production. These include the etching process, where unwanted material is removed from semiconductor wafers – the substrates on which circuits are assembled.

Helium is used in the production of silicon wafers, a vital component of computer chip manufacturing.
Metamorworks / Shutterstock

In space rockets, the non-flammable gas is used to flush out fuel lines and to pressurise fuel tanks.

Welding and fibre optic production requires helium to create inert, controlled environments.

Helium’s value comes from physical properties that are very difficult to substitute. In addition to its low boiling point, which makes it an excellent coolant, helium is inert and extremely light.

Its tiny molecules make it ideal for detecting the smallest leaks in pipelines and equipment.

Despite being the second most abundant element in the universe, helium is extremely rare on Earth. It forms underground over billions of years from the radioactive decay of uranium and thorium.

Because it is lighter than air, it escapes easily into the atmosphere and eventually into space, making it effectively non-renewable.

Manufacturing helium

Unlike most resources, helium is rarely produced on its own. In Qatar and other countries, helium is produced as a by-product of liquefied natural gas (LNG) production.

That means the supply of helium depends entirely on the production of natural gas: when gas production drops, so does helium output.

This is exactly what has happened in Qatar, where attacks on gas facilities have suspended both gas and helium production.

Exporting helium is not simple. It requires highly specialised cryogenic containers to keep it extremely cold during transport. These shipments must pass through narrow trade routes such as the Strait of Hormuz, making the supply chain vulnerable to political conflict.

Other countries have tried to develop helium production to reduce reliance on Qatar. Iran has worked to extract helium from its South Pars Gas Field, but sanctions have made this difficult. China, meanwhile, has been building the infrastructure to make its own helium and is prospecting for new reserves to diversify supply.

The US has the world’s largest helium reserves, stored in Amarillo, Texas. Originally established in 1925 to supply the airship industry, the reserve became a global strategic buffer that helped stabilise prices.

In recent decades, however, the US sold off much of the stockpile under the Helium Stewardship Act of 2013, reducing this safety net.

Adapting to pressure

However, there are ways that countries could adapt to a squeeze in global helium stocks.

Stockpiling: keeping reserves of helium for critical applications.

Substitution: limiting helium use to applications where its unique properties are essential.

Recycling: recovering helium from industrial or scientific processes, though this is difficult because helium easily escapes containment.

Diversification: Expanding production in multiple countries and exploring new reserves, as China is currently doing.

These measures could help alleviate future fluctuations in helium supply. But none are quick fixes. That’s why the disruption to supplies caused by the situation in the Strait of Hormuz is being felt around the world.

Gavin D. J. Harper 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 world’s supply of helium is being threatened by the Iran war – https://theconversation.com/the-worlds-supply-of-helium-is-being-threatened-by-the-iran-war-278811

April 2, 2026

Traveller’s tummy: why going on holiday can affect your bowel habits – and what you can do to prevent it

Source: The Conversation – UK – By Kate Grimshaw, Associate Clinical Fellow, Dietetics, Manchester Metropolitan University

Changes to our normal routine can throw our bowels out of whack. S Prodution/ Shutterstock

Travelling abroad is something many of us look forward to. It’s a chance to break free from the norm, discover new sights, try new foods and do things we might not normally have a chance to do.

But sometimes, our body has other plans – and our long-awaited holiday is spoiled by changes in our bowel habits. From bloating and discomfort to constipation and diarrhoea, travellers’ tummy is a well-recognised issue. Here’s why it happens – and what you can do to prevent it from ruining your plans.

Our bowels get used to how we normally eat and drink. They don’t really like great changes in that routine. Anything out of the ordinary will have some sort of effect on how they work.

This is why constipation (defined as having fewer than three bowel movements in a week, with straining and hard or dry, lumpy poo) can be a common problem in travellers.

Constipation lasting a few days into the holiday is probably due to dehydration. This is especially the case if you’re on holiday in a hot country, as you’ll be sweating a lot. Drinking more alcohol than you might normally have at home can also make dehydration worse.

Add to this a change in diet – such as irregular eating times and having fewer fruits and vegetables – and our bowels become sluggish and the constipation can get worse.

Finally, we tend to get a lot less exercise while on holiday. As exercise – particularly walking and cycling – helps stimulate bowel movements, that’s another reason why we may suffer from constipation.

Stress and potentially jet lag may also play a role in holiday constipation. Plus, recent research has shown that some people are just more prone to experiencing constipation while travelling.

On the other hand, some people experience episodes of diarrhoea on holiday.

One of the most common culprits behind traveller’s diarrhoea is gastroenteritis (an “upset tummy”), which is caused by eating contaminated or spoiled food.

But changes in diet can also be a common cause. Eating high-fat meals or drinking more alcohol than normal can both lead to episodes of diarrhoea.

Drinking a lot of fruit drinks can cause it too, due to their high fruit sugar (fructose) content. Similarly, strong tea and coffee can also have a similar effect due to the caffeine in them.

Finally, prolonged sun exposure can lead to diarrhoea as the body struggles to regulate internal temperature.

It’s possible to have episodes of both diarrhoea and constipation while on holiday. Most people find they experience diarrhoea first, which can cause dehydration if the lost fluids aren’t replaced by drinking enough, which can go on to cause constipation.

Preventing traveller’s tummy

So what can you do to reduce the likelihood of upset bowels on your holiday?

A young man wearing a backpack drinks water from a plastic bottle. — Staying hydrated is one key piece of advice.
Jemi Alpian/ Shutterstock

First, think about the area you’re travelling to. In some regions, there’s a higher risk of food and water contamination. Check advice on vaccinations and any specific advice for the places you will be visiting regarding food and water safety.

Other things you can do to look after your bowels on holiday include:

Keep your fluid intake up – ideally with water or naturally sweetened drinks;
Eat plenty of fruit and veg – especially ones that are similar to what you normally eat;
Limit your fruit juice intake to just one drink per day;
Walk after every meal if you can, to keep your digestive system working;
Eat regularly and avoid missing meals to keep a routine for your bowels to work with;
Avoid overly large meals – particularly those containing a lot of fat;
Try not to consume alcohol in excess.

What to do if you are affected

If you find you still come down with symptoms of constipation or diarrhoea on holiday, there are a number of things you can do.

For constipation, first and foremost, increase your fluid intake and take some fruit juice drink over the day. The water will soften your stool and the juice will encourage more water into your stool.

You should also try to increase the amount of fibre that’s in your diet. This can include snacking on dried fruit or adding flax or chia seeds to food. But make sure you’re drinking enough fluids, as too much fibre without water can have the opposite effect. You could also take an over-the-counter remedy, such as a fibre supplement or a laxative.

For diarrhoea, over-the-counter medication (such as loperamide) can be useful to stop the symptoms. Take this as soon as you get symptoms. Diarrhoea can cause dehydration, so to prevent that from happening, make sure you take an oral rehydration solution (such as Dioralyte) and drink plenty of water.

If your diarrhoea is accompanied by a high temperature or bloody or mucusy poos, do not take any over-the-counter medication and seek medical help immediately. This may be a sign of a more serious infection that requires specific medication.

Once you return home, it may take another few days for your bowel habits to return to your normal pattern. If any symptoms persist for more than a few days, it may be worth speaking with your GP.

Kate Grimshaw 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. Traveller’s tummy: why going on holiday can affect your bowel habits – and what you can do to prevent it – https://theconversation.com/travellers-tummy-why-going-on-holiday-can-affect-your-bowel-habits-and-what-you-can-do-to-prevent-it-279126

April 2, 2026

Four reasons why the new DC cinematic universe may fail (again)

Source: The Conversation – UK – By Roman Pavlyuchenko, Lecturer in Marketing, University of Bath

Marvel and DC have been captivating the world with their superheroes and supervillains for almost a century. Characters like Spider-Man (Marvel) and Superman (DC) are global household names whose recognition rivals that of world leaders.

For most of their history, Marvel and DC have gone toe-to-toe in comics, cartoons, TV and films. In 2008, Marvel made a breakthrough with its Marvel Cinematic Universe, an ongoing series of interconnected films and TV shows. Overall, it is the highest-grossing film franchise in history, with 2019’s Avengers: Endgame also being the highest-grossing franchise film ever made.

Forced to compete, DC responded with its own cinematic universe (2013-2023) that featured Man of Steel (2013), Batman vs Superman: Dawn of Justice (2015), Justice League (2017) and The Suicide Squad (2021). But it flopped both commercially and critically, forcing an abrupt ending in 2023 with Aquaman: The Lost Kingdom.

Now, in 2026, DC is attempting a revival. The home of Batman and Superman is launching a brand new cinematic universe, with director James Gunn leading the charge. The flagship Superman film was released in 2025, the second film with David Corenswet in the lead role, and Supergirl is dropping this July.

In total, 23 new films and shows have been announced, and DC is on a media blitz promoting its comeback. The timing could not have been better; Marvel is reeling from its own string of disappointments, such as 2021’s Eternals, 2023’s The Marvels, and 2025’s Thunderbolts*, all of which performed rather poorly at the box office given their big budgets.

Can DC pull it off this time around? My ongoing research into mega-franchises such as Marvel, DC and Warhammer, suggests not.

One of the reasons is DC’s failure to understand the psychology of mega-franchise consumers, even after Marvel’s multi-year success from 2008 onwards, and DC’s own failures. Below are four research-backed issues that could start posing serious problems for DC soon.

1. Lack of stylistic diversity

James Gunn is the genius director who gave Marvel the Guardians of the Galaxy franchise, its much praised (and highly successful) comic relief. His 2025 Superman for DC shared the same light-hearted humour and quirky dialogue. And going by the trailer, this year’s Supergirl looks to be similar in tone.

However, a universe cannot be built on quirkiness alone. Dozens of fans I interviewed uniformly praised the impeccable variety of styles that Marvel has managed to deliver since 2008. Some films are darkly funny (Deadpool), and some are dead serious (Eternals). And Marvel is very good at shuffling styles to keep viewers perpetually entertained.

This roller-coaster unpredictability is what drives the success of mega-franchises. If every film was just another spin on Guardians of the Galaxy, consumers could quickly lose interest.

2. Getting the pacing wrong

Last year’s Superman barraged consumers with a cavalcade of characters from DC’s roster, including Superman himself, but also Mister Terrific, Green Lantern, Metamorpho and Hawkgirl, to name a few. Which means DC is doing what it did in 2017, when its Justice League film introduced several major characters all at once.

In contrast, my research shows that fans prefer slower pacing, where characters are introduced first on their own and then aggregated into major spectacles such as Marvel’s Avengers. If the pacing is more measured, consumers cultivate an emotional stake in the characters’ stories. But if dozens of characters are introduced at the same time without proper grounding, who can blame audiences for not caring enough?

3. Over-reliance on obscure characters

Mega-franchises thrive on huge rosters of characters. However, it is important to first focus on just a few popular characters to get that “I know them!” effect. Here, Marvel did an excellent job promoting its biggest heroes first. Its first film featured the iconic Iron Man, quickly followed by mainstays like Captain America, Hulk and Thor. They already existed in the popular consciousness – which is exactly what Marvel counted on.

In this regard, DC’s release schedule leaves much to be desired. A few major characters (Aquaman) are meshed with minor episodic villains (Clay Face) and obscure heroes that have not seen major action in decades (Sergeant Rock).

Meanwhile, one of DC’s biggest characters, Batman, is not even getting his own film (the 2022 film starring Robert Pattinson was not part of this DC universe, but something called DC Elseworlds). If consumers refuse to become comic book nerds to enjoy a two-hour flick, whose problem is it?

4. The missing ‘big picture’

Mega-franchises such as Marvel and DC are famous for their massive life-or-death dramas. This is what drives audience engagement and gives a mega-franchise its purpose.

As my interviewees attest, the fact that such purpose emerged early on in Marvel’s oeuvre is what made it successful. From the start, audiences knew that everything was leading to the Avengers team-up. And, when The Avengers was released, it established Thanos as the archenemy and ensured that all threads led to him. The resulting film, 2019’s Avengers: Endgame, tied everything together in a massive spectacle that also happens to be the highest-grossing franchise film in history.

For now, the new DC universe can’t see the wood for the trees. As such, last year’s flagship film Superman did not seem to establish any major threats, cosmic events, supervillain archenemies, or any meaningful connection to any upcoming characters except Supergirl.

Instead, it opted for a local conflict between Superman and his arch-rival Lex Luthor. And, looking at the upcoming releases, it appears that the Justice League (DC’s version of Marvel’s Avengers) film is not even on the list.

Releasing a bunch of seemingly unrelated superhero offerings harks back to the early 2000s, when both Marvel and DC tried to reinterpret various characters in a series of disconnected standalone films. With audiences accustomed to major interconnected film sagas, this approach will not suddenly work in 2026. If audiences don’t know where the road is going (and, with mega-franchises, it is a long road), who can blame them for not taking it?

While DC’s comeback is sorely needed, the odds are that the current version is just not it. However, DC has always found ways to rebound, and it is still an iconic brand adored by millions (myself included). Like many fans, I await with baited breath to see how this new universe expands – or not.

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, The Conversation UK may earn a commission.

Roman Pavlyuchenko 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. Four reasons why the new DC cinematic universe may fail (again) – https://theconversation.com/four-reasons-why-the-new-dc-cinematic-universe-may-fail-again-277550

April 2, 2026

Le sabar, ce rythme sénégalais qui fait vibrer les quartiers et s’exporte dans le monde

Source: The Conversation – in French – By Aurélie Doignon, enseignante-chercheuse en sciences de l’éducation, CY Cergy Paris Université

Au loin, on entend les sons des sabars (musique et chorégraphie du Sénégal, centrée sur un ensemble de tambours du même nom et des danses collectives) dont les symphonies rythmiques se dévoilent en s’approchant. Dans les rue des quartiers Gueule Tapée ou de la Médina de Dakar, en après-midi ou la nuit, nous nous retrouvons dans un cercle, délimité par des chaises en plastiques louées par les organisateurs et fermé par les musiciens.

Seul le son va au-delà de cette assemblée et entraîne des enfants à imiter les adultes, en marge du grand cercle. Il s’agit de fêter un baptême, un mariage, un anniversaire. Les musiciens jouent les rythmes dans un ordre précis et les participants entrent quelques secondes pour danser dans le cercle, seul ou à plusieurs.

Le danseur dirige les musiciens qui doivent s’adapter aux mouvements, entraînant un jeu, voire une compétition entre les deux. Dans les sabars diurnes, les participantes viennent glisser des billets dans les mains ou la bouche du musicien joueur de tama (tambour d’aisselle) ou du soliste. Dans les sabars de nuit, le public donne indifféremment aux musiciens, danseurs, ou encore aux chants louangés.

En tant que spécialiste des danses et pratiques culturelles en Afrique en l’Ouest, j’ai notamment étudié le sabar en m’intéressant à la manière dont il se transmet et se pratique dans les quartiers. Dans cet article, j’explique pourquoi cette tradition reste au coeur de la vie sociale et culturelle des quartiers.

Un art qui mêle rythme et danse expressive

Le sabar est un phénomène culturel qui prend plusieurs formes (visible et audible) dans les quartiers populaires au Sénégal. Il désigne à la fois un ensemble de percussions traditionnelles (7 tambours différents), un rythme et une danse expressive pratiqués chez les Wolofs, une des communautés du Sénégal. Ecouter les tubes de mbalax (genre musical sénégalais) à la radio, c’est retrouver des sons de sabar mélangés à des arrangements actuels.

Alors que ces sons permettaient jadis de communiquer, le sabar est aujourd’hui surtout utilisé à des fins festives : baptêmes, mariages, anniversaires, fête de tontine, spectacles pour enfants (faux lions), ou encore première partie des combats de lutte (le lutteur défile avec son écurie, s’échauffe et intimide son adversaire). On retrouve également les rythmes sabar à l’occasion de rituels thérapeutiques (cérémonies de Ndeup).

Les évènements sabar sont réalisés grâce au concours des griots : musiciens, laudateurs, chants panégyriques (tassou), danseurs. Pour la réalisation d’un évènement, une rue est balisée : par l’installation d’un barnum au milieu de celle-ci et la location de chaises en plastique ainsi que d’une sonorisation (pour les fêtes nocturnes). L’espace peut aussi être délimité par des pneus, ou des spots de lumière. Enfin, dans le cadre des spectacles pour enfants, appelés « Simbs Gaïndé » ou « faux lions », des bâches sont tendues afin de faire payer l’entrée.

Le nom des rythmes du sabar répond à ceux de la vie quotidienne : Ceebu jën, par exemple, se traduit littéralement par « riz au poisson », du nom du plat national sénégalais. Il est le rythme le plus rapide. Fass tient quant à lui son nom du quartier éponyme de Dakar, marqué par une importante tradition de lutte sénégalaise. Walo-Walo renvoit à un groupe culturel du Sénégal, portant le même nom.

Le Sabar au coeur des célébrations de la vie de quartier

Forme la plus représentée des sabars de nuit, le mot tànnëbéer signifie d’ailleurs « conversation nocturne ». Il est le lieu d’expression des artistes professionnels et le public est autant composé d’hommes que de femmes, très apprété·es. Le tànnëbéer est un espace de visibilité pour les organisateurs, mais surtout pour les danseurs, qui y opèrent des logiques de distinctions afin d’assoir leur notoriété et de mettre en valeur leur image, leur danse.

C’est aussi le lieu pour inventer un « bàkk » (enchaînement où tous les musiciens jouent sur le même rythme, avec de multiples moments saccadés qui permettent de mettre en avant des parades humoristiques) ou de performer devant de préférence une caméra qui filme (par exemple, l’émission « Dakar ne dort pas » ou un téléphone, afin de partager la captation sur les réseaux sociaux.

Les évènements de sabars diurnes sont plutôt l’apanage des femmes : hormis les musiciens qui sont des hommes griots, ce sont les femmes qui dansent et célèbrent l’évènement – une matrescence, un mariage.

Imprégnés des rythmes sabar dès l’enfance lorsque l’on vit dans les quartiers populaires, l’incorporation de la danse s’effectue par imitation des femmes que les enfants accompagnent. Il sert alors de repère et d’apprentissage pour les jeux sororaux ou de séduction. C’est le lieu où les filles et les femmes peuvent s’extraire de la pudeur requise dans l’espace public.

La rue se révèle être un réel espace d’apprentissage des aînés en direction des plus jeunes, mais aussi d’apprentissages entre pairs dans l’enfance ou plus tard pour les jeunes adultes souhaitant se professionnaliser. En effet, aujourd’hui la transmission de la danse et de la musique ne s’effectue plus uniquement au sein des lignées de griots : des espaces d’apprentissages se sont ouverts comme les ballets, qui font fonction de formation et de diffusion de la musique et de la danse.

Professionalisation et rayonnement international

Devenir danseur de sabar à un niveau professionnel relève d’un entrelacs de propositions formelles et informelles d’entrée dans l’art. De fait, une nouvelle professionnalisation apparaît, portée par l’internationalisation des clips vidéo de la world music (catégorie musicale qui regroupe des styles traditionnels ou populaires du monde), mais aussi par la recherche de nouveaux corps et de nouvelles gestualités des chorégraphes de danse contemporaine.

De mes entretiens auprès d’une quarantaine de danseurs et danseuses de sabar et managers de ballets (réalisés dans le cadre de ma thèse de doctorat en sciences de l’éducation), apparaît une nouvelle professionnalisation, qui déconstruit les habitus de la société wolof et décloisonne cette société à castes (les griots étant souvent perçus comme une classe basse et dévalorisée).

Ainsi, des formations artistiques émergent sur le continent africain et les clips musicaux, s’intégrant au cœur même de la globalisation, des technologies et des réseaux de communication (visionnage et partage de vidéos de danse grâce aux smartphones dans la rue), deviennent les références et font désormais autorité dans les carrières professionnelles artistiques.

On observe aussi une vraie mise en place de communauté de pratiques des danseurs et de danseuses, au sens de Lave et Wenger: la participation au centre de la pratique, la mise en réseau et la construction de sens.

A la fois ancrée dans une culture urbaine et intergénérationnelle, le sabar permet ainsi de faire commun, de rassembler un quartier. Il permet de surcroît d’articuler une dialectique local-global avec sa diffusion sur les scènes internationales. L’internationalisation du sabar est en marche : à l’occasion des dernières coupes du monde masculines de football et de rugby, la chanteuse Gala a ainsi entonné son tube phare accompagnée de danseuses et de danseurs de sabar.

Aurélie Doignon 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. Le sabar, ce rythme sénégalais qui fait vibrer les quartiers et s’exporte dans le monde – https://theconversation.com/le-sabar-ce-rythme-senegalais-qui-fait-vibrer-les-quartiers-et-sexporte-dans-le-monde-272293

April 2, 2026

Pourquoi l’Afrique a besoin d’une banque verte pour développer ses propres technologies renouvelables

Source: The Conversation – in French – By Michael Olabisi, Assistant Professor in the Department of Community Sustainability (CSUS) and the department of Agricultural Food and Resource Economics (AFRE), Michigan State University

Le changement climatique représente un défi majeur pour les moyens de subsistance de nombreuses personnes dans les pays africains, qui n’ont pourtant qu’une infime part de responsabilité dans ce phénomène. La multiplication des phénomènes météorologiques extrêmes (inondations, vagues de chaleur et sécheresses) aggrave considérablement la faim, l’insécurité et les déplacements de populations. Le continent détient environ 30 % des minéraux indispensables à la future transition vers l’abandon des combustibles fossiles. Cependant, l’Afrique exporte principalement ces matières premières, laissant aux entreprises d’autres pays le soin de récolter les fruits de la fabrication de technologies à faible émission de carbone et d’infrastructures numériques. Les économistes spécialisés dans le développement durable Michael Adetayo Olabisi et Howard Stein proposent la création d’une nouvelle « banque verte » africaine comme solution.

Comment fonctionnerait la banque verte africaine ?

Notre vision est que cette banque soit créée par les gouvernements africains sous la forme d’une sorte de banque publique, détenue collectivement par les pays d’Afrique. Une telle banque aurait la capacité d’accéder à des financements internationaux qui ne sont pas accessibles aux pays pris individuellement.

La gestion, le capital et la structure de vote seraient entièrement contrôlés par les pays africains. Cela permettrait d’éviter les problèmes évidents rencontrés par d’autres organisations panafricaines. Celles-ci dépendent souvent trop fortement de l’aide des donateurs, ce qui a sapé la prise de décision souveraine. (Par exemple, 42 % des droits de vote de la Banque africaine de développement sont contrôlés par des pays non africains.)

À l’instar du système bancaire japonais, la banque verte africaine aurait la possibilité de prendre de petites participations dans les projets ou les entreprises bénéficiant de prêts. Cela permettrait à la banque de suivre le projet et de générer des revenus.

Nous proposons que la banque soit composée de sept divisions. Cela lui permettrait de fournir différents services complémentaires, de combler les lacunes en matière de capacités, tout en permettant à chaque division de se spécialiser. Les divisions de services que nous proposons sont les suivantes :

Production d’énergie verte.
Activités agricoles et chaîne de valeur associées utilisant des technologies vertes.
Soutien à la transformation et à la fabrication à partir de minéraux critiques tels que le lithium et le cobalt. (Ces minéraux bruts sont généralement envoyés à l’étranger pour être transformés en composants destinés aux énergies renouvelables.)
Fabrication et services liés à l’adaptation au changement climatique, tels que le soutien aux entreprises africaines qui fabriquent et installent des systèmes d’irrigation goutte à goutte solaires pour les zones touchées par la sécheresse due au changement climatique.
Une division d’investissement chargée d’attirer et de faciliter les investissements étrangers vers les industries vertes clés des pays africains.
Un service de vulgarisation verte. Celui-ci proposerait des consultations d’experts en ingénierie, en sciences et en politique industrielle sur la manière de mettre en place des projets de transition vers les énergies renouvelables couronnés de succès. Un modèle similaire existe à Taïwan.
La septième division serait la société holding. Elle gérerait les parts de propriété dans les divisions énumérées ci-dessus. Elle se spécialiserait dans le suivi et le compte rendu de l’avancement des projets.

La banque verte africaine fournirait des financements, mais elle ne serait pas seulement une institution financière. Ce serait une organisation continentale de politique industrielle visant à soutenir et à stimuler toutes les activités nécessaires en Afrique pour une transition vers une économie durable fondée sur les énergies renouvelables.

Les banques régionales de développement et les institutions financières internationales au service des gouvernements africains ont un bilan médiocre en matière de promotion et de financement en général, et de l’énergie verte et de l’industrie manufacturière en particulier.

Cette banque est ce dont l’Afrique a besoin pour enfin rompre avec le modèle colonial de longue date consistant à extraire et à exporter des matières premières.

L’architecture financière internationale, avec sa hiérarchie des devises, rend l’accès au financement climatique difficile et coûteux, et laisse les pays les plus pauvres d’Afrique à la traîne par rapport au reste du monde. Par exemple, l’Afrique subsaharienne n’aura accès qu’à 9 % des fonds dont elle a besoin pour atténuer le changement climatique entre 2024 et 2030. Il s’agit de loin du niveau de financement climatique le plus faible au monde.

Le continent manque également de banques de développement nationales et sous-régionales spécialisées dans l’industrialisation verte. Une banque verte pourrait rassembler en un seul lieu des compétences rares : des ingénieurs de haut niveau, des scientifiques, des planificateurs industriels et des experts financiers.

En quoi cela changerait-il le fonctionnement actuel du financement climatique à l’échelle mondiale ?

L’Afrique et d’autres régions ont reçu des promesses de financements pour l’adaptation au changement climatique par les pays du Nord qui sont à l’origine du changement climatique.

Nous proposons que ces pays allouent les coûts de transition à la banque verte, afin qu’elle dispose d’une base de capital en devises fortes. Les pays africains devraient également contribuer à la banque, en fonction de la taille de leur produit intérieur brut. Les fonds versés à la banque devraient être un mélange de devises des différents pays africains et de devises fortes.

Des dépôts en or pourraient être utilisés à la place des devises fortes. Des obligations seraient émises en Afrique et sur les marchés internationaux pour financer des projets verts.

La banque verte accorderait des prêts en devises africaines et non africaines à des projets soutenus ou garantis par l’État. Elle financerait ainsi l’industrie verte. Le volume de financement accordé serait proportionnel à la contribution de chaque pays au capital. Nous pensons que les remboursements pourraient parfois être libellés dans un panier de devises.

La banque serait le moteur de l’industrialisation verte. Cela pourrait contribuer à stabiliser les monnaies de la région et favoriser la dédollarisation en donnant aux pays africains la possibilité de rembourser leurs prêts en devises fortes avec des monnaies locales. Le pouvoir du dollar américain s’en trouverait également réduit si les pays africains créaient des usines pour fabriquer des composants destinés à l’énergie verte et les vendaient sur les marchés d’exportation.

En tant que dépositaire de nombreuses devises, la banque pourrait également faciliter les transferts au sein de l’Afrique. Par exemple, les paiements provenant d’un parc solaire en Tanzanie vers une usine de cellules solaires au Kenya ou en Éthiopie pourraient être crédités directement sur le solde de chaque projet auprès de la banque. À terme, la banque pourrait devenir une chambre de compensation pour les devises africaines, réduisant ainsi la nécessité de les convertir en dollars américains avant les transactions.

Comment la banque verte africaine fonctionnerait-elle avec les autres banques de développement ?

Les pays à revenu élevé pourraient se montrer sceptiques à l’idée de confier des fonds de financement climatique à des gouvernements qu’ils perçoivent comme corrompus ou techniquement moins compétents. La banque verte offrirait un canal transparent et responsable pour le financement climatique. Cela pourrait rassurer les prêteurs et les bailleurs de fonds existants. Cela faciliterait également le cofinancement avec des institutions telles que la Banque mondiale et les banques régionales de développement, à condition qu’elles acceptent les priorités de la banque verte africaine.

Les grandes banques africaines de développement, telles que la Banque africaine de développement et la Banque africaine d’import-export, s’orientent vers des priorités davantage alignées sur le climat. Mais il n’y a aucune preuve claire de progrès vers un financement adapté au changement climatique

Nous proposons que la banque verte travaille en étroite collaboration avec d’autres banques de développement à mesure que les objectifs communs évoluent. Parallèlement, elle devrait continuer à se concentrer sur la manière dont la politique industrielle peut être utilisée pour renforcer la résilience des pays face au changement climatique.

Quels sont les principaux obstacles à sa mise en place ?

La nécessité d’une nouvelle banque pour relever les défis industriels, financiers et climatiques du continent est incontestable. La création d’une telle banque ne sera pas une tâche facile. Elle nécessitera un consensus entre les pays du continent. Les pays du Nord devront également être disposés à allouer des fonds destinés à la lutte contre le changement climatique à cette nouvelle organisation.

L’ordre international est actuellement fracturé. Face aux inquiétudes croissantes concernant les puissances dominantes et leurs comportements concurrents dans le monde d’aujourd’hui, le moment est peut-être venu pour les nations indépendantes de forger de nouvelles alliances afin de contribuer à bâtir un avenir meilleur pour l’Afrique.

Michael Olabisi a bénéficié d’un financement de l’International Development Economics Associates (IDEAS).

Howard Stein bénéficie d’un financement de l’International Development Economics Associates (IDEAS).

– ref. Pourquoi l’Afrique a besoin d’une banque verte pour développer ses propres technologies renouvelables – https://theconversation.com/pourquoi-lafrique-a-besoin-dune-banque-verte-pour-developper-ses-propres-technologies-renouvelables-279503

April 2, 2026

L’eau claire du lac Léman, bonne nouvelle ou symptôme d’invasion ? Le cas de la moule quagga

Source: The Conversation – in French – By Elora Chatain, Doctorante, Inrae

Moules quagga sur un tuyau au fond du lac Léman. Linda Haltiner/Eawag

L’eau du Léman, lac franco-suisse, n’a jamais été aussi limpide, mais ce n’est pas forcément une bonne nouvelle pour le plus grand lac d’Europe occidentale. Derrière cette apparence de carte postale se cache en réalité une invasion silencieuse : celle de la moule quagga, qui filtre massivement l’eau, au risque de bouleverser en profondeur l’équilibre du lac. Des espèces de poissons pourraient être menacées, mais aussi les activités humaines : cette espèce colonise aussi, en effet, les conduites permettant l’approvisionnement en eau.

Depuis 2015, l’eau du Léman, lac frontière entre la France et la Suisse, devient progressivement cristalline. Une aubaine pour les baigneurs : visibilité parfaite, reflets couleur turquoise… un léger air des Maldives en plein cœur de l’Europe !

Mais derrière cette carte postale séduisante se cache une question dérangeante : une eau trop claire est-elle forcément synonyme de bonne santé écologique ? Car ce changement spectaculaire n’est ici pas dû à un miracle naturel, mais en bonne partie à l’action silencieuse d’une minuscule bivalve d’à peine deux centimètres : la moule quagga.

Et si cette transparence nouvelle semble anodine, voire réjouissante, elle est en réalité le symptôme visible d’un bouleversement profond. Car sous la surface du Léman, l’équilibre du lac est en train de se redéfinir autour d’un envahisseur durablement installé. Cela pourrait à terme entraîner le déclin du phytoplancton et des poissons qui en dépendent, ainsi que des proliférations d’algues.

Jusqu’à deux litres d’eau filtrée par jour… et par moule !

Discrète, cette moule filtre l’eau avec une redoutable efficacité : jusqu’à deux litres d’eau filtrés par jour et par moule. À première vue, cela paraît insignifiant, presque anodin. Mais multipliez ce chiffre par le nombre d’invidivus, en moyenne, 4 000 individus par mètre carré, et vous obtenez une machine biologique de filtration d’une puissance vertigineuse.

Aujourd’hui, c’est une armée silencieuse qui tapisse le fond du Léman et d’autres lacs en Europe et dans le monde, transformant en profondeur son fonctionnement. Car dans un écosystème, aucun changement d’une telle ampleur ne saurait être neutre. Cette filtration massive bouleverse les équilibres biologiques et complique sérieusement la gestion du lac.

Instrument de mesure scientifique entièrement colonisé par la moule quagga après une année d’immersion dans le lac à la profondeur de 8 mètres.
LéXPLORE, Sébastien Lavanchy

De nom scientifique Dreissena rostriformis bugensis, la moule quagga est une espèce exotique envahissante. Elle n’est pas née dans le Léman.

Originaire d’estuaires du bassin pontocaspien et plus précisément du delta du Dniepr, en Ukraine, elle a voyagé malgré elle – ou plutôt grâce et à cause de nous. Transportée dans les eaux de ballast des navires ou accrochée aux coques des bateaux, elle a traversé continents et océans, colonisant les Grands Lacs d’Amérique du Nord dès 1988, bien avant d’atteindre les lacs européens. Elle est morphologiquement et écologiquement proche de la moule zébrée (Dreissena polymorpha), autre espèce invasive bien connue, mais la quagga semble présenter une capacité d’adaptation encore supérieure.

La plongée sous-marine est l’un des moyens d’évaluer l’ampleur de la colonisation de la moule quagga en profondeur du lac.
S. Jacquet, Fourni par l’auteur

On estime que le Léman a été touché en 2015, le lac voisin du Bourget en 2017. Depuis 2022, l’espèce est aussi signalée dans le lac de Garde, première occurrence au sud des Alpes. Sa présence dans le lac Majeur est désormais fortement suspectée à la suite de la détection de son ADN.

Capable de s’installer durablement, de se reproduire rapidement et de se disperser à grande échelle, la moule quagga ne se contente pas de s’ajouter à l’écosystème : elle le redessine. Elle menace les espèces locales, modifie les équilibres biologiques et impacte directement certaines activités humaines.

Une niche écologique idéale pour l’envahisseur

Cette invasion a pourtant commencé à bas bruit. En 2015, un premier individu était observé à la station de Riva-Gare, dans le canton de Vaud en Suisse. Dix ans plus tard, le constat est saisissant : le fond du Léman est recouvert d’un véritable tapis de moules (jusqu’à 18 000 individus par mètre carré), avec une présence observée à des profondeurs supérieures à 150 mètres, bien au-delà de ce que l’humain peut explorer facilement.

Avec la plongée sous-marine, on peut voir à quel point la moule quagga colonise facilement le fond du lac et toutes sortes de substrats, ici une épave de bateau.

Cette expansion fulgurante de la moule quagga dans le Léman s’explique par une nourriture abondante, des courants favorables, l’absence de prédateurs naturels. Toutes les conditions sont réunies pour une colonisation éclair.

D’autant plus que l’espèce ne se laisse pas freiner par les contraintes extrêmes du milieu. Pression élevée, obscurité totale, températures basses ? Cela ne semble pas lui poser problème. Des individus ont été observés à 250 mètres de profondeur, certains atteignant des âges surprenants : plus de dix ans, là où sa longévité moyenne est plutôt de deux ou trois ans à proximité du littoral.

Comment parviennent-elles à survivre dans de telles conditions ? Peuvent-elles s’y reproduire ? À quel rythme ? Autant de questions auxquelles plusieurs équipes de recherche tentent aujourd’hui de répondre.

Une menace pour la production d’eau potable

Dans le fond du lac Léman, on peut retrouver de véritable tapis sous-marins de moules quagga.
Silvan Rossbacher/EAWAG

La moule quagga n’est pas difficile : elle s’installe sur tous les types de fonds. Sédiments divers, cailloux, roches… Même les fonds meubles de vase, limon et sable semblent lui convenir. Elle ne s’arrête toutefois pas aux milieux naturels.

Elle se fixe sur tous les supports disponibles sous l’eau, y compris les structures artificielles. Crépines, conduites et tuyaux de captage d’eau, notamment ceux destinés à la production d’eau potable, deviennent des supports de choix. À terme, ces infrastructures peuvent être partiellement ou totalement obstruées, compromettant l’approvisionnement en eau.

Les acteurs concernés n’ont alors d’autres choix que d’intervenir : nettoyages répétés, désencrassement des installations, ajout de filtres pour empêcher l’aspiration des moules… Autant de mesures indispensables, mais coûteuses. La présence de la moule quagga se traduit ainsi par un surcoût économique non négligeable, payé directement par les gestionnaires et indirectement par la collectivité.

Une bombe à retardement ?

Mais les dégâts causés par la moule quagga ne se limitent pas à une simple invasion de l’espace. Son mode de vie, discret en apparence, agit comme une bombe écologique à retardement pour le lac.

Gros plan sur le mollusque envahissant.
Fourni par l’auteur

Car la moule quagga est un organisme filtreur redoutablement efficace. En permanence, été comme hiver, elle aspire l’eau du lac et en extrait le plancton grâce à ses branchies. Cela n’a rien d’un détail.

Le phytoplancton, composante végétale du plancton, constitue le socle même de la vie lacustre : sans lui, c’est toute la chaîne alimentaire classique qui vacille. En effet, le phytoplancton nourrit le zooplancton (composante animale du plancton, dont les plus petits représentants peuvent aussi être ingérés par la moule). Or les alevins, ces poissons à peine éclos, dépendent directement de l’abondance du zooplancton pour survivre.

L’exemple des Grands Lacs nord-américains est sans appel. Là-bas, l’arrivée massive de la moule quagga a provoqué l’effondrement des populations de whitefish (ou corégone), un poisson emblématique qui est le pilier économique des pêcheries, tant au niveau local que dans les grands lacs profonds tempérés et froids en général : une catastrophe sociale et écologique.

Pour l’instant, le Léman n’a pas encore connu un tel scénario. Mais l’histoire nous a déjà montré comment cela peut finir.

Quand une eau « trop propre » devient un problème

En filtrant le phytoplancton à très grande échelle, les moules quagga rendent l’eau plus claire et donc plus transparente. À première vue, cela peut sembler positif, presque un argument touristique. Pourtant, cette clarté inhabituelle bouleverse, elle aussi, profondément l’écosystème.

Une eau plus limpide laisse en effet pénétrer la lumière plus profondément, stimulant la croissance des macrophytes, ces plantes aquatiques enracinées. Ces plantes, productrices d’oxygène, zones de nourricerie et de nurserie des poissons, constituent une composante importante du fonctionnement lacustre.

Mais les plantes et le phytoplancton sont en compétition et se disputent les mêmes nutriments. Résultat : plus les macrophytes prolifèrent, plus elles privent le phytoplancton de ressources, accentuant encore son déclin.

Ce cercle vicieux, connu sous le nom de boucle de rétroaction négative, s’autoentretient et verrouille le système dans un nouvel équilibre bien moins favorable à la biodiversité originelle du lac et à son fonctionnement pélagique, c’est-à-dire, dans la colonne d’eau. On parle alors de benthification des lacs (voir encadré ci-dessous).

Qu’est-ce que la benthification ?

La benthification est le processus par lequel l’énergie et la biomasse d’un écosystème aquatique sont déplacées de la colonne d’eau vers le fond (zone benthique).
Dans les lacs envahis par la moule quagga, ce phénomène est amplifié par sa forte capacité de filtration. En pompant le phytoplancton et les particules en suspension, la moule clarifie l’eau et transfère la matière organique vers les sédiments sous forme de fèces et de pseudofèces. Cette accumulation enrichit le fond, modifie les cycles des nutriments (notamment le phosphore) et peut favoriser le développement d’algues et de bactéries benthiques.
Les enjeux sont écologiques et socio-économiques : transformation des réseaux trophiques, déclin d’espèces planctoniques et de poissons dépendants du zooplancton, proliférations d’algues filamenteuses ou toxiques, et altération des habitats littoraux. La benthification liée à la moule quagga illustre ainsi une réorganisation profonde et durable du fonctionnement des lacs.

Alors, pourquoi ne pas simplement éliminer la moule quagga ?

La réponse est simple et brutale : parce qu’il est déjà trop tard et la colonisation du mollusque quasi totale. Imaginer son éradication complète du Léman relève aujourd’hui de la fiction, et tenter de le faire risquerait de provoquer un désastre écologique encore plus grave.

La seule option réaliste consiste désormais à apprendre à vivre avec cette espèce, comme c’est souvent le cas avec les espèces exotiques, à mieux comprendre son écophysiologie, à observer l’adaptation des écosystèmes, et surtout, à éviter que l’histoire ne se répète ailleurs. Cela passe par des gestes simples mais cruciaux : rincer soigneusement les coques de bateaux, le matériel de plongée et les équipements de loisirs avant de passer d’un lac ou d’un cours d’eau à un autre.

Car si la moule quagga a déjà gagné la bataille du Léman, la guerre contre sa propagation n’est pas encore perdue pour d’autres lacs. Et il reste à étudier et tester l’ensemble des pistes disponibles pour aider à la conservation des espèces natives du Léman, notamment en travaillant sur la restauration des habitats.

Jean-Nicolas Beisel a reçu des financements de l’ANR (projet QUALAG pour la période 2025-2029).

Stéphan Jacquet a reçu des financements de l’ANR (projet QUALAG pour la période 2025-2029)

Elora Chatain et Théo Gonin ne travaillent pas, ne conseillent pas, ne possèdent pas de parts, ne reçoivent pas de fonds d’une organisation qui pourrait tirer profit de cet article, et n’ont déclaré aucune autre affiliation que leur poste universitaire.

– ref. L’eau claire du lac Léman, bonne nouvelle ou symptôme d’invasion ? Le cas de la moule quagga – https://theconversation.com/leau-claire-du-lac-leman-bonne-nouvelle-ou-symptome-dinvasion-le-cas-de-la-moule-quagga-278611