¿Cómo podemos conocer la historia de la Tierra?

Source: The Conversation – (in Spanish) – By Laura Damas Mollá, Investigadora en Geología, Universidad del País Vasco / Euskal Herriko Unibertsitatea

Formaciones con estratos bien visibles en Zumaia (Gipuzkoa, España). Guillermo Guerao Serra/Shutterstock

Este artículo forma parte de la sección The Conversation Júnior, en la que especialistas de las principales universidades y centros de investigación contestan a las dudas de jóvenes curiosos de entre 12 y 16 años. Podéis enviar vuestras preguntas a tcesjunior@theconversation.com


Pregunta formulada por el curso de 2º de la ESO del Instituto de Educación Secundaria Miguel de Unamuno, en Gasteiz (Álava)


Nuestro planeta es mucho, muchísimo más antiguo que cualquier civilización humana. Sus 4 500 millones de años de historia han dejado numerosas huellas en las rocas, y la geología es la ciencia que se encarga de descifrarlas para que podamos leer los diferentes capítulos del “libro de la Tierra”, con tramas que se entrelazan.

Hablan los sedimentos

Antes que nada, recordemos que las rocas tienen varios orígenes: a través de magma o lava se forman las ígneas y por transformación de otras rocas, las metamórficas. Pero aquí las que más nos interesan, de momento, son las del tercer grupo: las sedimentarias.

Las rocas sedimentarias nacen al acumularse partículas, más o menos finas, generadas por la descomposición y erosión de rocas que afloran en relieves elevados como montañas. Estas partículas son transportadas por distintas vías (ríos, viento, glaciares…) hacia las zonas de acumulación. Así, los sedimentos se van depositando, capa a capa, en niveles más o menos horizontales: los estratos.

Estratos de roca en Muskiz (Bizkaia, España).
Laura Damas Mollá

Según la llamada ley de horizontalidad de los estratos, establecida por el científico danés Nicolás Steno en el siglo XVII, el estrato inferior es el más antiguo. El problema es que no nos los encontramos siempre así.

Acantilados del Eoceno (hace entre 56 y 33,9 millones de años) formados por una alternancia de dos tipos de rocas: areniscas y lutitas. Aquí, los estratos se disponen verticalmente. San Sebastián, Gipuzkoa.
Laura Damas Mollá

Al estudiar las rocas sedimentarias, el primer dato que debemos deducir es dónde se depositaron sus materiales, o sea, saber si se formaron en mares, ríos, lagos…. Los restos fósiles de seres vivos nos pueden proporcionar la solución del problema. Así, una roca caliza con fósiles de organismos marinos, como moluscos o corales, surgió en un ambiente tropical de aguas poco profundas, porque la fauna es similar a la actual. Si esos fósiles se encuentran enteros podemos incluso llegar a reconstruir los arrecifes.

Por otro lado, si nos encontramos los fósiles rotos y mezclados, supondremos que algún tipo de corriente los ha removido y desplazado de su hábitat. En otras ocasiones, como ocurre con las areniscas, presentan finas líneas o lineaciones que marcan la dirección e incluso el sentido de las corrientes que transportaban los sedimentos, igual que pasa actualmente en la playa.

Estas piezas del puzle de la historia terrestre se interpretan según el principio del “actualismo”. Acuñado por el geólogo británico Charles Lyell en 1830, indica que “el presente es la clave para entender el pasado”.

Sección longitudinal de molusco bivalvo (rudista) del Cretácico, hace entre 143 millones y 66 millones de años. Cantera de Andrabide (Gautegiz Arteaga, Bizkaia).
Laura Damas Mollá

Detalles que delatan la edad

Con estas pistas es posible interpretar el ambiente donde se depositaron las rocas sedimentarias, pero aún no sabemos su edad. Para averiguarla también existen varias técnicas.

En primer lugar, los minerales que forman esas rocas contienen isótopos radioactivos, componentes químicos cuyo análisis nos permite saber cuánto tiempo llevan en la Tierra. Este método se basa en la desintegración de un isótopo “padre” que se va transformando de forma progresiva a lo largo del tiempo en su “hijo”. Al conocer la proporción existente entre ellos en la muestra se puede obtener su edad.

En el caso de la célebre técnica del carbono-14 se necesitan muestras con un origen orgánico, por lo que no se puede aplicar en muchas rocas y minerales. Además, la “vida” de ese isótopo es de poco más de 60 000 años. Para rocas, minerales y fósiles utilizamos otras relaciones de isótopos radioactivos, como el uranio/torio o el uranio/plomo, que permiten dataciones de entre 500 000 años y varios miles de millones de años, más adecuadas para conocer la larga historia de la Tierra.

Y una curiosidad: ¿sabías que existe también una técnica para saber la edad de la última vez que ha visto la luz del sol un grano de cuarzo? Se llama luminiscencia ópticamente estimulada y se utiliza para estimar la antigüedad de muestras de entre 1 000 y 500 000 años.

Pero estas herramientas no sirven para todo tipo de rocas, así que también usamos otros métodos de datación. El más conocido consiste en examinar la variación del contenido fósil a lo largo del tiempo; es decir, la evolución. La vida de la Tierra se transforma a lo largo del tiempo, y encontrar determinadas asociaciones de fósiles nos permite establecer un rango de edad para los estratos. Aunque los más famosos son los grandes fósiles, como los dinosaurios, normalmente utilizamos microfósiles que se estudian con lupas.

Rocas sometidas a “torturas” geológicas

Pero la historia de las rocas está incompleta si solo averiguamos el ambiente donde se forjaron y su edad. Diferentes procesos geológicos hacen que rocas nacidas en fondos marinos, por ejemplo, formen parte de las montañas actuales. Porque desde que se produce el depósito de los materiales hasta la actualidad, las rocas sedimentarias sufren un proceso que se llama diagénesis: se calientan, se aplastan por enterramiento y experimentan diversos cambios en sus componentes (algunos se disuelven, otros se transforman, otros se fracturan…).

La mayor parte del tiempo, una roca sedimentaria está sometida a esas “torturas”, que podemos entender y ordenar cronológicamente. Para ello utilizados unos microscopios especiales, llamados petrográficos, y láminas de rocas de 0,3 mm de espesor.

Y por si esto fuera poco, los estratos no siempre se encuentran en posición horizontal, como las capas de una tarta. Igual que cuando empujamos un mantel con la mano, las fuerzas de las placas tectónicas pliegan los estratos rocosos. Los geólogos tenemos que “leer” también los capítulos protagonizados por las rocas ígneas, que nos cuentan la historia de las erupciones volcánicas del pasado, y las metamórficas, que nos hablan de transformaciones de unas rocas en otras.

Así, poco a poco, reconstruimos la biografía del planeta, desde las variaciones ambientales a la evolución de la vida. Comprender esa historia nos permite entender los cambios que están ocurriendo hoy en día y reflexionar sobre nuestro breve capítulo como homínidos, ya que la Tierra seguirá transformándose más allá de nuestra presencia en ella.

Si miras a tu alrededor y te pones las gafas de geólogo o geóloga, descubrirás qué historias conservan las rocas para saber hacia dónde vamos.


La Cátedra de Cultura Científica de la Universidad del País Vasco colabora en la sección The Conversation Júnior.


The Conversation

Laura Damas Mollá no recibe salario, ni ejerce labores de consultoría, ni posee acciones, ni recibe financiación de ninguna compañía u organización que pueda obtener beneficio de este artículo, y ha declarado carecer de vínculos relevantes más allá del cargo académico citado.

ref. ¿Cómo podemos conocer la historia de la Tierra? – https://theconversation.com/como-podemos-conocer-la-historia-de-la-tierra-266404

How we move, gesture and use facial expressions could be as unique as a fingerprint

Source: Radio New Zealand

The way someone walks, talks, smiles, or gestures gives a clue to who they are. Whether through the flick of an eyebrow, the rhythm of our walk, or the tilt of a head, movement speaks volumes.

And my recent paper shows that people may have their own movement fingerprint. This is a style of movement that is characteristic of a person’s identity. So, someone who uses expressive facial gestures might also speak with animated hand movements or walk with a lively gait. These consistencies could form a motion fingerprint that is unique to the individual.

First, let’s explore how faces move and why this matters.

– Published by EveningReport.nz and AsiaPacificReport.nz, see: MIL OSI in partnership with Radio New Zealand

First subpoenas issued as Donald Trump’s ‘grand conspiracy’ theory begins to take shape

Source: The Conversation – UK – By Robert Dover, Professor of Intelligence and National Security & Dean of Faculty, University of Hull

In recent weeks, Donald Trump’s supporters have begun to align around the idea that a Democrat-led “grand conspiracy” – potentially involving former president Barack Obama – has been plotting against the US president since 2016. The narrative is that the 2016 Russia investigation, which resulted in the Mueller inquiry was part of this deep-state opposition to Trump, as was the investigation into the January 6 riot at the US Capitol.

The focus of the fightback by Trump’s supporters is in Miami, where a Trump-appointed US attorney, Jason A. Reding Quiñones, has begun to issue subpoenas to a wide range of former officials.

This has included former CIA director John Brennan, former FBI counterintelligence official Peter Strzok, former FBI attorney Lisa Page and former director of national intelligence James Clapper, all of whom were involved in the federal investigation into alleged links between Russian intelligence and Trump’s 2016 presidential campaign.

The way the so-called conspiracy is unfolding will feel familiar to anyone who has watched US politics closely in the past decade. There’s been a constant stream of allegations and counter-allegations. But the narrative from the Trump camp is that the powerful “deep state” forces have been arrayed against the president. The “two-tier” justice system that has persecuted Trump can only be rebalanced by pursuing those who investigated him in 2017 and 2021.

The Grand Conspiracy contains similarities with other prominent conspiracy theories and how they spread. The QAnon movement, whose most famous claim is of a global paedophile ring run out of a Washington pizza parlour involving senior Democrats, is one where disparate claims are sporadically and partially evidenced. The political potency of these claims does not sit in the individual pieces of evidence but in the overarching story.

The story is that hidden government and proxy networks manipulate the truth and judicial outcomes and that only through pressure from “truthers” (what many people in the US who believe conspiracy theories call themselves) will wrongdoers be brought to account. Once these ideas are popularised, they take on a momentum and a direction that is difficult to control.

Campaign of ‘lawfare’

Soon after his inauguration, Trump set up a “weaponization working group” within the Department of Justice. Its director, Ed Martin, said in May that he would expose and discredit people he believes to be guilty, even if the evidence wasn’t sufficient to charge them: “If they can be charged, we’ll charge them. But if they can’t be charged, we will name them. And we will name them, and in a culture that respects shame, they should be people that are ashamed.”

In the US the norm has been to “charge crimes, not people”, so this modification fundamentally changes the focus of prosecutors.

Former FBI director James Comey responds to his indictment by grand jury in September.

The recent subpoenas in Florida show this principle at work, effectively making legal process into the punishment. Even without full court hearings on specific charges, being forced to provide testimony or documents creates suspicion around those who are targeted. Criticism from legal officials that this is a “indict first, investigate second” method suggests that this is a break from historical norms.

Lawfare, defined as “legal action undertaken as part of a hostile campaign”, doesn’t require a successful prosecution. It merely requires enough investigative activity to solidify a narrative of suspected guilt and enough costs and pressure to seriously inconvenience those affected by it. In the new era of digital media, it’s enough to degrade the standing of a political opponent.

In that way, political retaliation has become a prosecuting objective. This is clear from what the US president has indicated in his frequent posts on his social media platforms for his enemies, such as former FBI director James Comey, who investigated his alleged links to Russia, or Adam Schiff, the senator who led his impeachment in 2019.

Hardball politics or authoritarianism?

Political scientists argue that authoritarianism is something that happens little by little. Some of these steps involve using state power to target political opponents, degrading checks and balances and making loyalty a legal requirement.

There are reasons to believe that the US seems to be tracking this trajectory currently, certainly when it comes to using the Justice Department to harass the president’s political enemies and pushing back against court judgments while attacking the judges that have issued them.

Further slides towards authoritarianism are possible because of the political potency of contemporary conspiracy movements. The right-wing QAnon movement, for example, has been exceptionally agile. It has offered its followers identity, community spaces and a logic that encourages active participation, exhorting believers to “do your own research”, for example.

In the wake of the near daily addition of material from the investigations into the allegations that the late financier, Jeffrey Epstein, ran a sex trafficking ring, involving some influential US citizens, many American citizens have concluded as a general truth that their elites do hide things. This makes it far simpler for broader conspiracies to gain traction and more difficult for politicians and journalists to work out what is conspiracy and what is evidence. This is creating a problematic feedback loop – hints of wrongdoing fuel public suspicion, and public suspicion fuels the idea of a further need for investigation.

But to suggest that anyone has control over this would be wrong. These movements can just as easily consume those seen as supporters as they do those seen as enemies. Marjorie Taylor-Greene’s determination to release the full and unredacted Epstein files could well produce negative outcomes for some Maga supporters, including prominent ones.

So, the transformation of legal process into public spectacle in America is suggestive of a drift towards authoritarianism. America’s famous “constitutional guardrails” of separation of powers, independent courts, juries and counsels will be pivotal in preventing this. They will need to stand firm.

The grand conspiracy theory might be more about seeking to isolate, and financially and emotionally exhaust opponents, while at the same time destroying America’s system of checks and balances. It might work.

The Conversation

Robert Dover 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. First subpoenas issued as Donald Trump’s ‘grand conspiracy’ theory begins to take shape – https://theconversation.com/first-subpoenas-issued-as-donald-trumps-grand-conspiracy-theory-begins-to-take-shape-269542

After resignations at the top, the BBC faces a defining test: what does impartiality mean now?

Source: The Conversation – UK – By Tom Felle, Associate Professor of Journalism, University of Galway

Taljat David/Shutterstock

The sudden departure of the BBC’s director general and head of news marks a moment of real consequence for British public service broadcasting.

Tim Davie and Deborah Turness’s resignations followed controversy over an inaccurately edited clip in a BBC Panorama documentary about Donald Trump. Opponents of the BBC seized on this as further evidence of widespread bias at the broadcaster. It has now become a flashpoint in the wider political and cultural battles surrounding the corporation.

The resignations come as the BBC enters a decisive period. The renewal of its royal charter in 2027 will define the corporation’s funding model and public purpose for the next decade. At the same time, the BBC faces a hostile political climate, sustained financial pressure and a rapidly fragmenting audience.

Recent controversies – from the Panorama edit to earlier disputes over social media conduct and political coverage – have reignited debate about the broadcaster’s duty of “impartiality”. Yet in today’s febrile information climate, it is fair to ask whether that duty remains fit for purpose.

Media regulator Ofcom defines impartiality as “not favouring one side over another”, but also as ensuring “due weight” is given to the evidence. That distinction matters: impartiality is not the same as neutrality. It demands that news be fair, accurate and proportionate – not that every claim be treated as equal.

Impartiality under pressure

The BBC’s crisis, as academic and commentator Adrian Monck observes, is not simply a matter of poor governance, but “the sinking of a ship of the twentieth century British state, dependent on conditions that no longer really exist”.

Impartiality as a professional norm took shape in the mid-20th century, when it became central to the BBC’s mission under its 1947 royal charter. It emerged in a period when there was still broad agreement on shared facts, and a civic space where citizens could reason together even when they disagreed.




Read more:
BBC has survived allegations of political bias before – but the latest crisis comes at a pivotal moment


This era has broken down over the past 20 to 25 years, with the rise of digital platforms and populist politics that eroded traditional journalistic gatekeeping. Today’s information environment is shaped by technology companies, populist leaders, political strategists and partisan media outlets. All have strong incentives to create confusion and distrust. When political figures deny evidence, distort facts or lie as strategy, reporting their claims as equal to verified facts is not neutrality or impartiality, it is distortion.

Davie understood this tension. Under his leadership, the BBC tried to clarify the meaning of impartiality, strengthen editorial standards and reinforce trust in its reporting.

Yet the organisation, like many news outlets worldwide, is caught in a bind: accused of bias from both the left and the right – and while in the past this might suggest a fair balance, in today’s climate it is often weaponised.

As the sociologist Niklas Luhmann has noted, the function of news is to create a shared reality, a minimal consensus about what exists and what matters. When that consensus collapses, the public sphere itself begins to fragment and journalism loses the ground on which democratic discourse depends.

Younger audiences, who are more likely to access news mediated through influencers they perceive as authentic and relatable, are less engaged with traditional news brands. A Reuters Institute study found that young people increasingly turn to personalities rather than established outlets, or avoid news altogether because they see it as untrustworthy or biased.

The broader global trend is unmistakable. Public service broadcasters in the US, Australia, Canada and across Europe are facing declining audiences, reduced funding, politicised attacks and competition from platforms that prioritise outrage and identity performance. The BBC is not unique in this struggle, but because of its scale and cultural importance, the stakes are higher.

Public service media under siege

The BBC is imperfect. It suffers from institutional caution, uneven performance and a reluctance at times to confront its own errors. Yet it remains one of the few media organisations in the world still committed to verification rather than performance.

Its public service mandate, however strained, is one of the last structural defences against the current media culture: one dominated by outrage merchants and ideological broadcasters whose business model is provocation rather than truth.

Once a public sphere is shaped primarily by rumour and outrage, it becomes almost impossible to restore a shared sense of reality. The alternative is visible already in GB News, Fox and Breitbart, where conflict and grievance have displaced evidence.




Read more:
Perfect storm of tech bros, foreign interference and disinformation is an urgent threat to press freedom


The question now is not whether the BBC should continue to defend impartiality, but which version of impartiality it intends to defend. If impartiality means placing all claims side by side regardless of evidential grounding, it becomes a mechanism for laundering falsehood into public discourse. But if it means rigorous truth-telling, proportionate scrutiny and transparency about what we know and how we know it, then it remains both viable and essential.

BBC chair Samir Shah has apologised for the Panorama edit, describing it as an “error of judgement”. But it has exposed how fragile impartiality has become as both a principle and a perception. In an environment where trust is brittle, even minor lapses are magnified into institutional political positions. Impartiality is now judged as much by perception as by practice.

The resignations at the top of the BBC make this moment all the more precarious. The next leadership will determine whether the BBC becomes a smaller, defensive organisation that avoids offence, or a confident public service broadcaster that accepts that truth-telling will sometimes be mistaken for taking sides. Only the latter approach offers any chance of sustaining public relevance.


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The Conversation

Tom Felle 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. After resignations at the top, the BBC faces a defining test: what does impartiality mean now? – https://theconversation.com/after-resignations-at-the-top-the-bbc-faces-a-defining-test-what-does-impartiality-mean-now-269575

Why musicians are leaving Spotify – and what it means for the music you love

Source: The Conversation – UK – By Andrew White, Senior Lecturer in the Department of Culture, Media & Creative Industries, King’s College London

Vera Harly/Shutterstock

Spotify is haemorrhaging artists. In the last few months alone a handful of indie bands have exited the streaming platform. If that includes some of your favourite musicians, you may be wondering how best to support them.

Among the artists leaving the platform is indie band Deerhoof. They reacted to the news that Spotify’s founder Daniel Ek had used his venture capital firm to lead a €600 million (£528 million) investment in Helsing, a German defence company specialising in AI. Their statement said: “We don’t want our music killing people.”

This sentiment chimes with the attitudes of the many listeners who cancelled their Spotify subscriptions after the platform ran recruitment ads for ICE, the US’s controversial Immigration and Customs Enforcement agency.

The exodus reflects a general concern that major tech companies are too cosy with the Trump administration. Spotify’s US$150,000 (£114,000) donation to Trump’s inauguration ceremony was cited by Canadian musician Chad VanGaalen as one of the reasons for his departure from the platform.

But these protests are as much driven by a recognition of ongoing structural problems with music streaming business models as they are with recent events. Music streaming platforms like Spotify, Amazon Music and Apple Music allocate revenue to artists on a pro-rata basis. This means that artists on each platform are entitled to a proportion of the overall revenue from streaming. This percentage is calculated by identifying the proportion of their streams that represent the total number of streams on the platform.


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There is therefore no direct financial relationship between listeners and the artists that they listen to. This is an opaque structure that fuels musicians’ sense that they are not receiving fair remuneration.

The number of songs on Spotify and similar platforms has grown exponentially in recent years. By Spotify’s own admission, the growth in revenue from music streaming has resulted in a deluge of AI-generated content, with 75 million spam tracks being removed over 12 months in 2024-25.

Despite this success, it can be assumed that many such tracks remain undetected and that there are therefore significant amounts of money being given to fake musicians at the expense of real artists. Spotify’s openness to some AI content, exemplified by the continuing presence of the AI band Velvet Sundown in its catalogue, does not assuage artists’ concerns.

The bundling of different types of content can make the allocation of payments to musicians much more complicated. While Spotify’s music and podcast revenue streams are separate, its audiobooks have been bundled into its premium subscription. The effect of this change in 2024 has been to lower the royalty rate of the songwriters whose music appears on its platform. Around the same time the company decided to remove payments for songs that were streamed less than 1,000 times. This is likely to disproportionately affect artists struggling to get a foothold in the music industry.

Despite all this, overall revenue continues to grow. Spotify claims that the US$10 billion it paid to the music industry in 2024 was the largest ever annual payment by any retailer. Annual rises in the price point of its subscription in the last two years means that its growth will likely sustain. That its latest quarterly figures revealed an operating profit of US$680 million seem to bear this out. This improvement in Spotify’s finances exacerbates musicians’ feeling that they are not getting their fair share.

Where to go next

So where can you go if you decide to leave Spotify? Given that its main competitors also use the pro-rata payment model and offer the same menu of unlimited music, then probably not to them.

Some streamers have experimented with user-centric models of payment whereby listeners pay directly the artists of the songs they stream. This, though, has had limited success, with Deezer capping its scheme to 1,000 streams per person per month, while Tidal ended its own experiment after two years.

There are, though, smaller platforms which deploy user-centric models of payment. Sonstream was popular for a while with independent artists, but at the time of writing its website has only basic functionality.

Resonate is a cooperative with a pay-for-play user-centric model which gives artists and rights-holders 70% of revenue, with the remaining 30% being ploughed back into the business. But the one that appears to come closest to combining an “artists-first approach” with a critical mass of musicians and listeners is Bandcamp. Each time a user purchases something on the platform, 82% of that transaction goes to the artist and/or their label. These payments have amounted to US$1.6 billion to date for not only streamed music, but cassettes, CDs, vinyl records and t-shirts too.

This last observation reflects a wider trend within the music industry and among listeners. That is that the encroachment of algorithms and AI on the curation and listening of music has led many to ditch streaming platforms altogether. This has encouraged artists to be more innovative, with many experimenting with other means of distributing their music, including selling CDs and downloads directly, and setting up their own DIY digital platforms.

For Spotify and other streaming platforms there is then a wider existential question about the extent to which it is possible to construct an economically viable business model that satisfies listeners while ensuring that musicians receive fair remuneration for their creativity.


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The Conversation

Andrew White 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 musicians are leaving Spotify – and what it means for the music you love – https://theconversation.com/why-musicians-are-leaving-spotify-and-what-it-means-for-the-music-you-love-269231

Flu season has started early in the UK – here’s what might be going on

Source: The Conversation – UK – By Conor Meehan, Associate Professor of Microbial Bioinformatics, Nottingham Trent University

The UK’s flu season is already well underway. simona pilolla 2/ Shutterstock

Flu season has got off to an early start this year in the UK – with cases spiking weeks earlier than in previous years. This has led to concerns that the UK may be on track for one of its worst flu seasons ever.

In the UK and other northern hemisphere countries, flu season tends to run from mid-November to mid-February. In the southern hemisphere, it runs from May to July.

It’s hard to know the exact number of flu cases the UK is currently seeing as most people don’t report when they have the flu. Most just stay in bed and recover. To get a picture of this year’s flu season, we rely on hospital data and GP reports. This usually only represents the most severe flu cases.

We know flu season is “starting” when about 10% of suspected cases come back positive for the influenza virus.

The UK’s flu season is already well underway – and weeks before it usually starts. This is because at the start of November we were already seeing 11% of daily tests come back positive for the flu. At the same time last year, just 3% of tests were positive. The UK crossed the 10% threshold a whole month earlier than it did last year.

School-aged children are currently most affected, with 38% of tests coming back positive for the flu – up from 30% just one week prior. Around this time last year, the number of children testing positive for flu was just under 7%.

A line graph depicting flu seasons starting from 2022 and going until this year, 2025.
Cases have spiked a month earlier than usual.
UK Health Security Agency

Similar increases have been seen elsewhere, such as in Japan and across Europe.

What’s causing this early flu season?

The UK’s flu vaccine uptake seems to be almost identical to previous years, so the increase in cases cannot be explained by a fall in vaccination rates.

One likely factor contributing to the UK’s early spike in flu cases is the strain of influenza virus that’s circulating.

Flu is caused by influenza viruses – mainly the influenza A virus. There are lots of variants of this virus, so they’re usually designated by a combination of H and N numbers. For example, H5N1 is the main cause of the ongoing avian flu pandemic in birds and other animals. Seasonal flu in humans is usually caused by H3N2 and H1N1.

The seasonal flu vaccine is designed to combat these two strains, as well as an influenza B virus alongside them. This vaccine tends to be between 20-70% effective at preventing the flu, depending on the year. The vaccine tends to be most effective for school-aged children, especially in preventing severe forms of the disease.

A new vaccine is developed every year as the circulating strains of influenza can mutate over time, reducing vaccine efficacy.

Twice a year (once for each hemisphere), the World Health Organization convenes an expert panel to decide, based on the strains that circulated last year, what strains of influenza should be used to build the vaccine for the coming flu season. The vaccine almost always includes an H1N1, H3N2 and influenza B strain.

Generally, building these vaccines based on what circulated previously is quite effective. This is because any genetic changes that occur in these strains between flu seasons aren’t large enough to render the vaccine ineffective.

But this year there seems to have been an exception. A new strain of influenza, influenza A H3N2 subclade K, is now infecting the majority of people. This strain has seven mutations that differentiate it from the previous H3N2 strain. This is many more genetic mutations than what’s usually seen between seasons.

It’s too early to know why this strain has developed so many genetic mutations. But we do know that these changes appear to have made this strain slightly more transmissible compared to previous strains.

The strain’s R number (the average number of people an infected person will go on to infect) increased from the usual 1.2 for influenza to 1.4. This means about 20% more people will be infected than we would normally expect.

Early research into this strain shows that the vaccine is still very effective in children at preventing severe forms of the disease. But in adults, effectiveness has dropped to between 30% and 40%.

A mother checks her child's temperature with a thermometer while resting her hand on the child's head. The girl is blowing her nose with a tissue.
School-aged children are currently most affected by this season’s flu.
Prostock-studio/ Shutterstock

However, we can’t say just yet whether reduced vaccine efficacy in adults and the new mutations to the H3N2 strain are the causes behind the current spike in flu cases.

It’s also too soon to know whether this year’s flu season will be more severe than in previous years. But based on its early start, the strain’s high R number and low vaccine effectiveness in adults, we might expect higher numbers than usual.

And, if we look at data from from southern hemisphere’s flu season – which usually gives us a good idea of what we should expect – Australia saw its worst flu season ever. They reported 10% more cases than in the previous year.

How to protect yourself

It’s important to note that, especially in children, the vaccine is still the best form of protection. Flu can be very severe in both the young and old, resulting in hospitalisation and sometimes death. Vaccination (including by those who regularly come in close contact with older and younger people) is key.

It’s also important to know how flu symptoms differ from those of the common cold so that you can recover and protect others from catching it. The presence of fever, headache and a strong cough typically indicate the flu.

If you have these symptoms, you should rest and follow standard flu guidance. Also remember you’re infectious for a week or so after symptoms start, so isolating at this time will stop the virus from spreading. Alongside getting the jab, wearing a mask and following good hand hygiene can help you avoid getting sick and prevent you from spreading the flu if you are sick.


If you’ve got a question about the flu vaccine that you’d like an expert to answer, please send them to: clint.witchalls@theconversation.com

The Conversation

Conor Meehan 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. Flu season has started early in the UK – here’s what might be going on – https://theconversation.com/flu-season-has-started-early-in-the-uk-heres-what-might-be-going-on-269619

Early climate models got global warming right – but now US funding cuts threaten the future of climate science data

Source: The Conversation – UK – By Gemma Ware, Host, The Conversation Weekly Podcast, The Conversation

bear_productions/Shutterstock

Since the 1960s, scientists have been developing and honing models to understand how the earth’s climate is changing. These models help predict the phenomena that accompany that change, such as stronger storms, rising sea levels and warming temperatures.

One such pioneer of early climate modelling is Syukuro Manabe, who won the Nobel prize in physics in 2021 for his work laying the foundation for our current understanding of how carbon dioxide affects global temperatures. That same year, a seminal paper he co-published in 1967 was voted the most influential climate science paper of all time.

Syukuro Manabe pointing to a chart.
Syukuro Manabe at the Geophysical Fluid Dynamics Laboratory.
Geophysical Fluid Dynamics Laboratory

In this episode of The Conversation Weekly podcast,  we speak to Nadir Jeevanjee, a researcher at the same lab in the National Oceanic and Atmospheric Administration where Manabe once worked. He looks back at the history of these early climate models, and how many of their major predictions have stood the test of time.

“ On one hand, we’ve gone way beyond Manabe in the decades since,” says Jeevanjee. “And on the other hand, some of those insights were so deep that we keep coming back to them to deepening our understanding.”

And yet, as climate negotiators gather in the Brazilian city of Belem on the edge of the Amazon for the Cop30 climate summit to hammer out new pledges on reducing carbon emissions and how to pay for climate adaptation, the data sources that climate scientists around the world rely on to monitor and model the climate are under threat from funding cuts by the Trump administration.

“We all do this work because we believe in its importance,” says Jevanjee. “And so the idea that the work isn’t necessarily valued by the present government, or that we wouldn’t be able to do it, or that somehow our lab and the models that it produces and all the science that comes out of it will be curtailed or shut, is alarming.”

Listen to the interview with Nadir Jeevanjee on The Conversation Weekly podcast, and read an article he wrote about five forecasts that early climate models by Suki Manabe and his colleagues got right.

This episode of The Conversation Weekly was written and produced by Katie Flood, Mend Mariwany and Gemma Ware. Mixing by Eleanor Brezzi and theme music by Neeta Sarl.

Newsclips in this episode from CNN.

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

The Conversation

Nadir Jeevanjee works for NOAA’s Geophysical Fluid Dynamics Laboratory, which is discussed in this podcast episode. The views expressed herein are in no sense official positions of the Geophysical Fluid Dynamics Laboratory, the National Oceanic and Atmospheric Administration, or the Department of Commerce.

ref. Early climate models got global warming right – but now US funding cuts threaten the future of climate science data – https://theconversation.com/early-climate-models-got-global-warming-right-but-now-us-funding-cuts-threaten-the-future-of-climate-science-data-269639

Kyiv’s European allies debate ways of keeping the cash flowing to Ukraine but the picture on the battlefield is grim

Source: The Conversation – UK – By Veronika Hinman, Deputy Director, Portsmouth Military Education Team, University of Portsmouth

The EU is considering a range of options as it tries to work out how to continue to fund Ukraine’s defence against Russia. There are three mechanisms presently under consideration. One is using Russia’s frozen assets to back a loan of €140 billion (£124 billion). Another is borrowing the money at interest, although this is not popular.

The third idea, which was proposed by Norwegian economists, is that Norway could use its €1.8 trillion sovereign wealth fund – the biggest in the world – to guarantee the loan. Their reasoning was that Norway, Europe’s biggest producer of oil and gas, has made an extra €109 billion from the rise in gas prices after Russia’s invasion.

The situation on the front has been largely static for months, although Russian forces have been making small gains in some key areas. The battles for the strategically important cities of Pokrovsk in the Donetsk region of eastern Ukraine and Huliaipole in the southern region of Zaporizhzhia are a good indication of the progress of the war in general.

It’s hard, amid the flood of disinformation, to accurately monitor from a distance the exact status of these two important battles. Each day brings fresh reports of multiple attacks and advances by Russian troops. There have also been reports that Russian units have captured Pokrovsk. This would be a serious blow for Ukraine, as it’s an important supply hub, with several roads and rail lines converging there.

But the US-based military think-tank the Institute for the Study of War (ISW), which uses geolocated footage on which to base its assessments, has determined that Russia is not yet in full control of Pokrovsk, having to date seized 46% of the city. ISW analysts say Russian military bloggers are “mounting a concerted informational campaign prematurely calling the fall of Pokrovsk, likely to influence the information space”.

The battle for Pokrovsk has raged for nearly 18 months now, without resolution – but with huge casualties on both sides.

Similarly, while the situation in Huliaipole is deteriorating for the Ukrainian defenders, “Russian forces will probably spend considerable time setting conditions for efforts to seize the settlement”, the ISW says.

It’s important to realise that Russian troops initially entered Huliaipole on March 5 2022 within weeks of its initial invasion the previous month, but were quickly pushed back by Ukrainian troops. Fighting has continued in the region ever since.

In other words while both sides have made some tactical gains, neither holds the strategic upper hand.

One thing is clear: despite the claims and counter-claims, both sides have suffered significant casualties. In June 2025, the UK Ministry of Defence estimated more than one million Russian troops have been killed or injured since the invasion in February 2022. But Russia still retains considerable reserves of troops to call on, and has not yet had to resort to full mobilisation.

Meanwhile Russia’s economy is holding up, despite western sanctions. The effect of the recent imposition of oil sanctions by the US has yet to be seen. At the same time, Russia’s continuing and thriving diplomatic, economic and military relationships with its “enabler ally” China, as well as others on the anti-west axis such as Iran and North Korea – which have been supplying Moscow with weaponry and troops, respectively – is helping it sustain its offensive efforts.

ISW map showing the state of the conflict in Ukraine, November 11 2025.
The state of the conflict in Ukraine, November 11 2025.
Institute for the Study of War

Financing Ukraine’s defence

Ukraine, meanwhile, is now almost entirely reliant on continued western support. Since Donald Trump took power in the US in January, the US stance towards Ukraine has shifted considerably and while Kyiv’s friends in Nato can continue to purchase US weaponry for Ukraine’s war effort, the US will not fund any of the purchases. Consequently, military aid to Ukraine has slowed considerably in the second half of 2025 – by up to 43% according to German research non-profit the Kiel Institute.

EU leaders voted in October to meet Ukraine’s “pressing financial needs” for another two years, but have yet to agree on a way of doing that. Using frozen Russian assets comes with a number of difficulties. These assets are held in Belgium by the securities depository Euroclear. But Brussels is wary of the move, arguing that a Russian lawsuit against the move, if successful, could leave Belgium liable.

The other obstacle is that it would need to be unanimously approved by EU member states, something that is thought highly unlikely. The idea of using frozen Russian assets has already been rejected by Hungary and Slovakia. And the recent victory of the populist ANO party in the Czech Republic could signal further isolation for Ukraine. One of the first gestures made by the new Czech government has been to remove the Ukrainian flag from the parliament building.

If Norway were willing to use its US$2 trillion sovereign wealth fund to guarantee a €160 billion loan to Ukraine, it would effectively bypass the need for EU unanimity. But the country’s finance minister, former Nato secretary-general Jens Stoltenberg, appeared to rule that out on November 12 when he said guaranteeing the whole amount was “not an option”.

What impact is this loan likely to make in the grand scheme of things? The funds supplied thus far have kept Ukraine from defeat, but have not enabled it to strike a decisive blow against Russia that would win the war or enable it to negotiate a just peace.

At the same time it is realistic to acknowledge that while a massive injection of funds would help Ukraine stabilise its economy and buy enough arms to give their troops a better chance on the battlefield, it cannot deliver the manpower, weapons or morale. In the end, this latest wave of aid may buy Ukraine time – but it’s unlikely to deliver victory.

The Conversation

Veronika Hinman 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. Kyiv’s European allies debate ways of keeping the cash flowing to Ukraine but the picture on the battlefield is grim – https://theconversation.com/kyivs-european-allies-debate-ways-of-keeping-the-cash-flowing-to-ukraine-but-the-picture-on-the-battlefield-is-grim-269541

L’opéra aux Amériques, un héritage européen revisité par les identités culturelles locales

Source: The Conversation – in French – By Frédéric Lamantia, Docteur en géographie et maître de conférences, UCLy (Lyon Catholic University)

Le Palais des beaux-arts de Mexico (en espagnol : Palacio de Bellas Artes) est le premier opéra de Mexico. Sa construction fut achevée en 1934. Xavier Quetzalcoatl Contreras Castillo , CC BY-SA

L’opéra s’est enraciné sur le continent américain en hybridant répertoires et techniques d’outre-Atlantique avec des récits, des rythmes et des imaginaires empruntés aux populations autochtones. Nous poursuivons ici notre série d’articles « L’opéra : une carte sonore du monde ».


Ne cherchant ni à copier ni à rompre avec l’histoire de l’opéra en Europe, l’histoire de l’opéra aux Amériques est plutôt celle d’un long processus d’acclimatation. La circulation des artistes et les innovations esthétiques y rencontrent des terrains sociaux, politiques et économiques spécifiques selon les pays. Si depuis le XVIIe siècle, Christophe Colomb a inspiré de nombreux opéras, cet art est aujourd’hui présent sur tout le continent où il met en exergue des éléments locaux du patrimoine culturel conjugués avec la matrice européenne.

En Amérique du Nord, et notamment aux États-Unis, l’art lyrique trouve ses origines dans les ballad operas anglais du XVIIIe siècle joués dans les premiers théâtres à Philadelphie ou à New York.

Au XIXe siècle, l’opéra s’implante comme un divertissement « importé » et rencontre un certain succès dont bénéficient l’Academy of Music (l’Opéra de New York) ou le Metropolitan Opera tandis que la Nouvelle-Orléans, foyer francophone, sert de tête de pont aux opéras français mais aussi italiens. Ces derniers, apportés par nombre d’immigrants en provenance de Rome, de Naples ou de Palerme, ont nécessité la construction de théâtres, comme celui de San Francisco.

Spécificités états-uniennes

Au XXe siècle, l’art lyrique possède ses hauts lieux aux États-Unis, tels que le Metropolitan Opera (Met) qui s’impose comme le champion des créations nationales impliquant des spécificités états-uniennes quant aux sujets, aux styles et aux voix.

La quête d’une couleur « nationale » passe par le recours à des matériaux amérindiens puis par l’intégration de langages musicaux afro-américains comme les spirituals, le jazz, le ragtime, le blues, jusqu’aux sujets explicitement liés à l’esclavage, à la ségrégation et aux droits civiques.

De Porgy and Bess à X : The Life and Times of Malcom X ou The Central Park Five, l’opéra devient un miroir social avec des œuvres qui se fondent dans le paysage culturel, sa grande diversité et les conséquences de celle-ci. Le progrès technique s’invite aussi à l’opéra avec des œuvres comme Le téléphone, opéra comique de Menotti. Parallèlement, le langage musical évolue, porté par le néoromantisme de Barber, la satire politico-sociale de Blitzstein, le minimalisme de Glass ou d’Adams.

En Amérique du Nord, une économie fragile

Sur le plan économique, l’écosystème lyrique états-unien comme canadien combine recettes propres, dons privés et mécénat, le rendant particulièrement vulnérable à des crises, comme celle survenue lors de l’épidémie de Covid qui a vu ses publics se contracter, tandis que les coûts de production restaient élevés. Le marketing de l’opéra innove sans cesse, contraint à une nécessaire démocratisation garantissant le renouvellement de ses publics, avec des représentations dans des lieux insolites – Ikea à Philadelphie –, et à une digitalisation de l’espace lyrique et de sa programmation.

Si des réseaux efficaces, comme Opera America ou Opera Europa, facilitent communication, diffusion et levée de fonds, d’autres solutions ont pu voir le jour pour sécuriser l’activité lyrique aux États-Unis, comme cet accord pluriannuel signé entre le Met et l’Arabie saoudite.

Hybridations en Amérique centrale

En Amérique centrale, l’art lyrique s’inscrit également dans l’espace urbain comme en témoigne le Palacio de Bellas Artes à Mexico. Conçu en 1901 et inauguré en 1934, ce bâtiment fusionne art nouveau par son extérieur en marbre et art déco pour l’intérieur de la salle, décorée avec des fresques monumentales. Le modèle architectural comme une partie du répertoire – Mozart, Strauss, Puccini ou Donizetti – sont européens, mais l’institution a aussi servi de carrefour aux arts mexicains à l’image du Ballet folklorique d’Amalia Hernández ou de créations de compositeurs locaux comme Ibarra, Catán ou Jimenez.

Le rideau de scène représentant les volcans Popocatépetl et Iztaccíhuatl symbolise ce lien entre opera house « à l’européenne » et imaginaires locaux. Dans cette zone géographique, l’hybridation architecturale et artistique s’opère dans les institutions nationales avec une volonté d’articuler répertoire européen et identité culturelle locale, tant du point de vue musical, iconographique que chorégraphique.

Offenbach-mania au Brésil

L’Amérique du Sud a connu un développement de son territoire lyrique dans les grandes métropoles, mais également dans des lieux insolites comme à Manaus, au Brésil, en pleine Amazonie, où le théâtre d’opéra était la sortie privilégiée des riches industriels producteurs d’hévéa tandis que la bourgeoisie de Sao Paulo, souvent proche de l’industrie du café se retrouvait en son opéra.

L’import d’œuvres européennes, notamment d’Offenbach ou de Puccini dont le succès fulgurant a inspiré de nombreux compositeurs locaux, a façonné le paysage lyrique sud-américain. On note que dans les années 1860-1880, Rio connaît une véritable Offenbach-mania et devient un creuset pour des hybridations diverses : de nombreuses œuvres sont traduites en portugais tandis que des troupes francophones sont régulièrement accueillies.

Dans le même temps se développent des parodies brésiliennes qui, sans copier Offenbach, procèdent à une « brésilianisation » du style par l’insertion de danses et rythmes afro-brésiliens – polca-lundu, cateretê, samba de roda – et par l’apparition de la capoeira sur scène. Naît alors un débat, ressemblant mutatis mutandis à la « querelle des Bouffons » française, opposant « art national » et « opérette importée » et aboutissant parfois à une « parodie de parodie » d’Offenbach !

Ces échanges lyriques montrent que les Amériques ne se contentent pas d’importer de l’opéra occidental, mais qu’elles transforment puis réémettent des œuvres vers l’Europe, enrichies d’un apport exotique.

En Argentine, l’opéra comme symbole de réussite sociale

En Argentine, Puccini triomphe en 1905 à Buenos Aires alors qu’il vient superviser la nouvelle version d’Edgar. Il consolidera sa notoriété grâce à ses succès sur les scènes latino-américaines avant de livrer en 1910, à New York, La fanciulla del West(la Fille du Far-West), western lyrique basé sur l’imaginaire américain. Dans une capitale marquée par une importante immigration italienne initiée dès les années 1880, l’opéra reste un symbole de réussite sociale.

Le Teatro Colon, érigé en 1908, opère une synthèse architecturale entre néo-Renaissance italienne et néo-baroque français, agrémentée de touches Art nouveau. Dotée d’une excellente acoustique et accessible sur le plan tarifaire, la salle s’impose comme un centre lyrique important sur le continent. L’art lyrique argentin reste ouvert à de nombreux sujets, comme en témoigne l’opéra Aliados (2013), d’Esteban Buch et Sebastian Rivas, évoquant les liens entre Margaret Thatcher et Augusto Pinochet, alliés à l’époque de la guerre des Malouines en 1982.

On trouve ainsi des traits communs à l’art lyrique sud-américain, associant grandes maisons emblématiques, appropriations esthétiques locales et coopérations internationales par-delà une vulnérabilité économique due à sa dépendance au mécénat.

Au Chili et en Bolivie, des lieux d’échanges et de métissage

Le cas du Teatro Municipal de Santiago inauguré en 1857 avec une architecture néoclassique française et toujours intact malgré de nombreux séismes, a été victime de crises budgétaires récurrentes mais développe depuis 2023 un partenariat avec l’Opéra National de Paris.

L’objectif est de permettre une circulation des savoir-faire au sein d’une coopération Sud-Nord au service de la formation de talents locaux. Le Chili accueille également un théâtre musical ouvert à des sujets politiques.

En Bolivie, le théatre Grand Mariscal de Ayacuchode, dans la ville de Sucre, construit en 1894 sur un modèle inspiré de la Scala pour accueillir des opérettes et des zarzuelas est devenu malgré son inachèvement un lieu patrimonial mêlant histoire locale et pratiques lyriques au croisement de l’Europe et des cultures andines.

Par ailleurs, ce métissage a donné naissance à des œuvres parfois anciennes comme cet opéra baroque datant de 1740 écrit par un indigène évangélisé en bésiro, dialecte ancien en voie de disparition.

De New York à Buenos Aires, l’opéra aux Amériques s’est bâti une identité singulière par sa capacité à assimiler apports européens et patrimoine culturel autochtone. Sur l’héritage des techniques et du répertoire européen sont venus se greffer des spécificités culturelles locales issues de traditions propres aux indiens, aux créoles ou aux populations afro-américaines. Loin d’un modèle importé à l’identique, il constitue un « palimpseste lyrique » où se côtoient Puccini, Offenbach, jazz et capoeira. Les voix de l’Amérique sont devenues l’écho d’un territoire lyrique complexe, où traditions culturelles et mémoires collectives s’incarnent dans un patrimoine musical et architectural singulier.

The Conversation

Frédéric Lamantia ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d’une organisation qui pourrait tirer profit de cet article, et n’a déclaré aucune autre affiliation que son organisme de recherche.

ref. L’opéra aux Amériques, un héritage européen revisité par les identités culturelles locales – https://theconversation.com/lopera-aux-ameriques-un-heritage-europeen-revisite-par-les-identites-culturelles-locales-268684

Enquête auprès de 2 400 professeurs d’EPS : « Nos élèves manquent de souffle et de force »

Source: The Conversation – in French – By David Matelot, Enseignant d’EPS, docteur en physiologie de l’exercice, Université Bretagne Sud (UBS)

Les performances des élèves français à un test d’endurance cardio-respiratoire, le Navette 20 mètres, ont diminué de 18 % entre 1999 et 2022. Konstantin Mishchenko/Unsplash, CC BY

Alors que les performances à l’endurance des élèves ont chuté de près de 18 % entre 1999 et 2022, l’éducation nationale commence à mesurer la condition physique des enfants en classe de 6e. Une vaste enquête menée auprès de 2 400 enseignants d’éducation physique et sportive révèle que ceux-ci constatent ce déclin, mais peinent à en faire une priorité, faute de temps, de moyens et de formation. Pourtant, améliorer l’endurance cardiorespiratoire et la force musculaire à l’école apparaît aujourd’hui essentiel pour prévenir les risques cardio-vasculaires et poser les bases d’habitudes durables. Une équipe de chercheurs propose cinq pistes pour redresser la barre.


Les performances des élèves français au Navette 20 mètres, un test d’endurance cardio-respiratoire, ont diminué d’environ 18 % entre 1999 et 2022. Pour comprendre cette évolution, nous avons interrogé environ 2 400 enseignants d’éducation physique et sportive (EPS) en collège et lycée. Plus de 90 % savent que l’endurance cardiorespiratoire et la force musculaire sont associées à une meilleure santé physique.

Parmi les répondants, 91 % considèrent que le niveau d’endurance des élèves a baissé ces vingt dernières années, et 66 % jugent qu’il en va de même pour leur force.

Travailler ces qualités physiques n’est pas une priorité en EPS

Cependant, comme le montrent les réponses ci-dessus, le développement de ces deux qualités physiques est un objectif plutôt secondaire de leurs cours. De plus, 47 % des enseignants considèrent que les objectifs de l’EPS dans les programmes officiels ne donnent pas une place prioritaire au développement de ces qualités, ce qui freine la prise en compte de cette problématique.

Le développement de la condition physique des élèves en EPS est difficile parce qu’il nécessite pour l’enseignant d’EPS de concevoir des cours adaptés à trois caractéristiques qui varient au sein des élèves d’une même classe : leurs niveaux de force et d’endurance cardiorespiratoire, leurs stades de croissance et de maturation, et leurs motifs d’agir.

Les résultats de ce questionnaire nous ont amenés à développer cinq pistes pour le développement des qualités d’endurance cardiorespiratoire et de force musculaire des collégiens et des lycéens.

Piste 1 : Proposer des pratiques « hybrides » motivantes pour tous les élèves

« La question des qualités physiques vient buter souvent sur le manque d’attrait pour les élèves d’un engagement dans des efforts […] il faut être habile pour habiller les situations et les rendre ludiques tout en travaillant les qualités physiques. »

Cette réponse illustre une difficulté importante à laquelle les enseignants d’EPS doivent faire face, qui semble également vraie chez les adultes comme le montrent les travaux sur le « syndrome du paresseux ».

Plus spécifiquement pour l’EPS, il semble important de s’intéresser au plaisir et au déplaisir ressentis par les élèves, car ces émotions influencent la construction d’habitudes de pratiques physiques durables. La difficulté principale ici est qu’un même exercice proposé à l’ensemble de la classe va susciter de l’intérêt et du plaisir chez certains élèves mais du désintérêt voire du déplaisir pour d’autres. Chaque élève peut en effet se caractériser par des « motifs d’agir » variés : affronter en espérant gagner, progresser pour soi-même, faire en équipe, vivre des sensations fortes…

Petites filles gym
Rendre les exercices attractifs est essentiel pour motiver les élèves.
Brett Wharton/Unsplash, CC BY

Les exercices dits « hybrides » sont une solution développée par des enseignants d’EPS : le principe est de proposer la même situation à tous les élèves, dans laquelle ils peuvent choisir leur objectif pour que chacun s’engage selon sa source de motivation privilégiée. Le « Parkour Gym » est une forme de pratique scolaire de la gymnastique artistique où les élèves composent un parcours en juxtaposant plusieurs figures d’acrobaties, en choisissant le niveau de difficulté. L’objectif pour tous est de réaliser ce parcours le plus rapidement possible, tout en réalisant correctement les figures acrobatiques choisies, qui rapportent des points selon leurs difficultés.

Cette pratique permet à chaque élève de se focaliser sur sa source de motivation privilégiée : améliorer son temps ou son score acrobatique, avoir un score final (temps et difficultés) le plus élevé possible, ou encore travailler spécifiquement la réalisation d’une acrobatie perçue comme valorisante ou génératrice de sensations fortes. Le travail ainsi réalisé en gymnastique, de par le gainage et les impulsions nécessaires, développe le système musculaire.

Piste 2 : Augmenter les temps de pratique d’EPS dans l’établissement

Le premier frein rapporté par les enseignants est le manque de temps en cours d’EPS, notamment au regard des multiples objectifs à travailler. Par exemple en Lycée Général et Technologique les programmes d’EPS contiennent cinq objectifs à travailler, en deux heures hebdomadaires. Une première solution qui apparaît serait d’augmenter le temps d’EPS obligatoire pour tous les élèves. Ou encore de prévoir des dispositifs de « soutien en EPS » avec des moyens supplémentaires dédiés aux élèves en difficulté dans cette discipline.

Des solutions existent également à moyens constants. La première possibilité est celle de l’association sportive scolaire qui existe dans chaque établissement, et qui propose des activités physiques et sportives aux élèves volontaires. Cette association est animée par les enseignants d’EPS de l’établissement, cette activité fait partie de leur temps de travail. Si les chiffres du graphique ci-dessous sont encourageants, il semble possible d’élargir encore davantage ces offres dans les collèges et lycées de France.

D’autres possibilités existent. L’équipe EPS du collège Les Hautes Ourmes (académie de Rennes) propose un dispositif intéressant, sur le modèle de ce qui est proposé en natation pour les non-nageurs, avec trois enseignants au lieu de deux qui interviennent sur deux classes en même temps. Ce fonctionnement permet de constituer des plus petits groupes de besoin encadrés par chaque enseignant, et de travailler une qualité physique ciblée prioritairement pour ce groupe (endurance cardiorespiratoire, vitesse, force et endurance musculaire, coordination, équilibre).

Enfin, l’académie de Limoges a mis en place des sections sportives scolaires « Sport-Santé ». Ce n’est plus la performance sportive qui est visée mais la recherche d’un bien-être physique, psychologique et social. La section donne l’opportunité aux élèves volontaires de s’impliquer dans la gestion de leur vie physique, en les sensibilisant à l’importance de la pratique sportive.

L’approche est axée sur la valorisation des réussites et de l’estime de soi, et propose des modalités de pratique novatrices et ludiques, adaptées aux spécificités des élèves. L’objectif est donc de donner ou de redonner le goût de la pratique physique à ces élèves, étape indispensable vers un mode de vie actif au-delà de l’École. Ces sections font partie, avec d’autres dispositifs, d’un réel système mis en place pour développer les qualités physiques de leurs élèves à différents niveaux. Nous espérons que cette démarche pourra se généraliser à d’autres Académies.

Piste 3 : Intégrer le travail des qualités aérobie et de force aux cours d’EPS

Les réponses aux deux questions ci-dessus indiquent qu’il serait intéressant de prévoir pendant les cours d’EPS plus de situations qui travaillent les qualités d’endurance cardiorespiratoire et de force musculaire des élèves. Celles-ci peuvent être stimulées et développées pendant toute la durée du cursus collège-lycée. Il est possible de développer ces qualités physiques pendant la pratique des activités physiques et sportives au programme en les intensifiant, ou alors lors de temps dédiés comme pendant un échauffement renforcé ou des exercices intermittents de haute intensité.

Piste 4 : Utiliser des tests physiques pour l’EPS

Parmi les répondants, 60 % des enseignants disent faire un test d’endurance cardio-respiratoire au moins une fois par an à leurs élèves, ce qui semble déjà élevé mais pourrait encore être généralisé. Pour la force seulement, 14 % des enseignants disent que leurs élèves font un test au moins une fois par an, et ils sont 63 % à ne jamais faire de tests de force pendant leur scolarité dans l’établissement.

Les tests physiques sont globalement assez peu exploités en France. En effet, aucune batterie de tests ni base de données nationale n’existe en France contrairement à d’autres pays (par exemple, les programmes Fitnessgram aux États-Unis, Youth-Fit en Irlande, ou Slofit en Slovénie). Mesurer les qualités physiques par des tests répétés met en évidence les progrès des élèves et améliore leur connaissance de soi, ces tests peuvent être un outil pour l’EPS.

Piste 5 : Renforcer la formation des enseignants

Globalement, les enseignants sont intéressés par une formation sur ce thème (cf. graphique ci-dessous). Si environ 80 % des enseignants disent avoir été suffisamment formés pour évaluer (83 %) et développer (78 %) l’endurance cardio-respiratoire de leurs élèves, concernant la force, ces chiffres descendent à 49 % pour son évaluation et à 58 % pour son développement.

Plusieurs études démontrent que les niveaux d’aérobie et de force des élèves sont liées à leurs risques de développer des pathologies cardio-vasculaires plus tard dans la vie, et plus globalement à leur espérance de vie. Cette association n’est connue que par 41 % des enseignants pour l’aérobie et par 22 % pour la force. La formation continue des enseignants d’EPS dans ce domaine pourrait donc également être renforcée.


Les auteurs tiennent à remercier François Carré, professeur émérite au CHU de Rennes, pour sa contribution à la rédaction de cet article.

The Conversation

Les auteurs 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 organisme de recherche.

ref. Enquête auprès de 2 400 professeurs d’EPS : « Nos élèves manquent de souffle et de force » – https://theconversation.com/enquete-aupres-de-2-400-professeurs-deps-nos-eleves-manquent-de-souffle-et-de-force-266684