Faut-il réviser les missions des banques centrales ?

Source: The Conversation – France (in French) – By Jean-Paul Pollin, Professeur émerite d’économie et de finance, Université d’Orléans

Les banques centrales sont incitées à prendre des décisions dont les motifs dépassent leurs objectifs traditionnels de stabilité des prix et des systèmes financiers. Mais en ont-elles la légitimité ? Cela ne risque-t-il pas d’affecter leur indépendance ? Ne faudrait-il pas alors engager une révision de leurs missions ?

Cet article est publié dans le cadre du partenariat les Rencontres économiques d’Aix–The Conversation. L’édition 2025 de cet événement a pour thème « Affronter le choc des réalités ».


On résume trop souvent les missions des banques centrales au maintien de la stabilité des prix, d’une part, et à la stabilité du système bancaire, d’autre part. Mais, en réalité, selon les mandats qui leur sont assignés et/ou selon la façon dont elles les interprètent, le champ de ces missions est généralement bien plus vaste.

Ainsi, la Fed est investie d’un « double mandat » : la stabilité des prix et niveau d’emploi maximum. D’autres banques centrales (dans des pays en développement) ont pour mission de stabiliser la parité de leur monnaie avec celle d’une devise étrangère… La Banque centrale européenne (BCE), de son côté, est censée, sans préjudice de l’objectif de prix, apporter un soutien aux politiques générales « en vue de contribuer aux objectifs de la Communauté ». Ce qui constitue un ensemble de missions potentiellement très (trop ?) large.

Par ailleurs, pour répondre aux crises qui se sont succédé, au cours des vingt dernières années, les autorités monétaires ont su modifier l’ordre de priorité de leurs missions et, parfois, en étendre le champ. Durant les crises financière puis sanitaire, elles ont accompagné les politiques budgétaires pour soutenir l’activité, mais aussi pour limiter le coût de l’endettement public en achetant massivement des titres de dettes publiques (des politiques dites non conventionnelles). Elles ont alors pris le risque d’accepter une « dominance budgétaire ». Ce qui a pu leur être reproché.




À lire aussi :
Quand les banques centrales s’emparent de la question du climat


Une liberté limitée

Mais ces observations ne signifient pas que les banques centrales ont toute liberté pour interpréter ou même compléter les termes de leurs mandats. Car l’aménagement de leurs missions se heurte au moins à deux contraintes majeures :

  • D’une part, on sait qu’il est sous-optimal de poursuivre plus d’objectifs que l’on a d’instruments (règle de Tinbergen). Or, même si les banques centrales peuvent (à la marge et si cela est pertinent) augmenter la gamme de leurs instruments, leur nombre est fatalement limité.

  • D’autre part, lorsque la politique monétaire pénètre dans un domaine qui relève aussi de la compétence d’autres volets des politiques économiques (par exemple, la politique budgétaire, industrielle ou sociale…), la coordination que cela suppose peut mettre en danger son indépendance et, donc, la crédibilité de ses objectifs censés orienter les anticipations des agents. Car toute collaboration avec d’autres décideurs (des agences ou le politique) ouvre l’éventualité de concessions susceptibles de dévier par rapport aux annonces. À cela s’ajoute le fait que l’indépendance en question met en cause la légitimité des autorités monétaires à prendre des décisions qui supposent des choix de nature politique, qui affectent par exemple la distribution des revenus ou des richesses. Peut-on, dès lors, laisser les banques centrales mener des politiques dérogeant à ce principe ? Notamment des politiques sélectives.

Aller au-delà de la régulation conjoncturelle ?

Comme bien d’autres institutions, les banques centrales ont été interpellées par la montée des désordres environnementaux et en particulier par leur probable influence sur la stabilité des systèmes financiers. Mais les réactions des autorités monétaires à cette sollicitation ont été divergentes voire discordantes : Jerome Powell (Fed), par exemple, a répondu que la Fed n’était pas un « climate policymaker »


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Il n’empêche qu’en 2017, s’est constitué un réseau comprenant des banques centrales et des régulateurs, Network for Greening the Financial System, qui compte aujourd’hui 145 membres, afin d’étudier et de suggérer des solutions à cette question qui devrait devenir cruciale dans les années à venir. Il en ressort notamment des propositions visant à renforcer les réglementations prudentielles pour prendre explicitement en compte les risques portés par les actifs détenus par les institutions financières qui sont la contrepartie de financements d’investissements contribuant aux déséquilibres écologiques dits « investissements bruns ». Ce qui est théoriquement tout à fait justifié, même si la mise en pratique de cette idée est compliquée et prendra sans doute du temps.

Par ailleurs, certaines banques centrales se sont engagées dans des refinancements privilégiés pour les « actifs verts » (c’est-à-dire compatibles avec la transition écologique) et, plus généralement, dans le « verdissement » de leur bilan. Il s’agit alors d’une sorte de retour à une politique de crédit sélective du type de celles qui avaient été pratiquées dans l’après-guerre, avant d’être balayée par la vague de libéralisation financière des années 1970-1980. On a alors considéré que les banques centrales ne devaient pas contrarier le rôle des marchés dans l’allocation des capitaux et donc ne pas intervenir dans la formation des structures par terme et par niveaux de risque des taux d’intérêt. On se situe par conséquent ici aux limites, évoquées précédemment, des révisions envisageables.

France 24, 2025.

L’écueil des chocs d’offre

De façon plus générale, il est vraisemblable que, dans les années qui viennent, les politiques économiques vont se trouver davantage confrontées à des problèmes de régulation de l’offre plutôt que de la demande. Parce qu’il leur faudra principalement répondre aux chocs sur les conditions de production que vont entraîner les évolutions technologiques, les ruptures et la recomposition des échanges commerciaux et des chaînes de valeur, les éventuelles pénuries de matières premières… Au cours des années récentes, c’est bien à ce type de problèmes que les politiques conjoncturelles ont été confrontées : la crise sanitaire a provoqué une contraction de la production, puis des ruptures d’approvisionnement. Elle a été suivie du déclenchement de conflits armés occasionnant, entre autres, une hausse des prix de l’énergie et donnant lieu à un brusque retour de l’inflation.

Or, on sait que les politiques monétaires conventionnelles sont démunies pour répondre à des chocs d’offre, car dans ce cas l’ajustement des taux d’intérêt ne peut assurer à la fois la stabilité des prix et celle de l’activité. C’est d’ailleurs pourquoi plusieurs banques centrales ont souhaité flexibiliser leur objectif d’inflation en allongeant l’horizon de son calcul, en l’inscrivant dans une marge de fluctuation…

Au demeurant ces chocs d’offre génèrent des déséquilibres de caractère micro ou méso-économiques qui relèvent plutôt d’une politique du crédit apte à rétablir la compétitivité de la structure productive. Mais ceci nécessite alors une stratégie industrielle et des choix que des banques centrales indépendantes n’ont pas la légitimité (ni toutes les compétences) pour en décider. C’est, alors, qu’une coordination qu’une coordination entre les politiques économiques devient inévitable.

De nouvelles missions dans un système monétaire international en restructuration ?

D’un tout autre point de vue, ajoutons que nombre d’observateurs considèrent aujourd’hui que le dollar devrait perdre progressivement sa prédominance en tant que monnaie d’échange, de facturation et de réserve. La monnaie américaine tenait une place essentielle dans le système monétaire international qui avait été recomposé dans l’immédiat après-guerre. Mais cette place a été remise en cause par la fracturation, qui s’accélère, de cet ordre économique mondial, par la baisse du poids relatif de l’économie américaine et sans doute aussi par le fait que les États-Unis se sont affranchis des responsabilités qu’impliquait le « privilège exorbitant » dont bénéficie leur devise.

Dans le monde multipolaire qui semble se mettre en place, il serait juste et cohérent que d’autres monnaies, notamment l’euro et le yuan chinois, se substituent en partie à la monnaie américaine. C’est du reste une revendication ancienne de nombre de pays émergents, les BRICS+.

Ceci représenterait pour les monnaies considérées une « captation de privilège », mais imposerait aussi de nouvelles obligations. Il faudra faire en sorte que la parité de ces monnaies soit assez stable, libéraliser (en Chine) les mouvements de capitaux, introduire des monnaies numériques de banques centrales pour faciliter et réduire les coûts des règlements transfrontières…

Mais, aussi et surtout, assurer le développement de marchés financiers profonds et liquides, afin de rendre attractive la détention à l’étranger d’actifs émis dans les pays considérés. Ces exigences impacteront sans doute les missions des banques centrales, mais elles vont bien au-delà. Par exemple, la nécessité de conforter l’offre de placements suppose, en Europe, une unification des marchés de capitaux ainsi qu’une uniformisation des dettes publiques émises par les différents États de la zone. Ce qui renvoie à des initiatives que la banque centrale peut suggérer et accompagner, mais dont elle ne peut pas décider du fait de leur dimension politique.


Cet article est publié dans le cadre d’un partenariat de The Conversation avec les Rencontres économiques, qui se tiennent du 3 au 5 juillet, à Aix-en-Provence. Plusieurs débats y seront consacrés au rôle des banques centrales.

The Conversation

Jean-Paul Pollin 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. Faut-il réviser les missions des banques centrales ? – https://theconversation.com/faut-il-reviser-les-missions-des-banques-centrales-259461

Bill Moyers’ journalism strengthened democracy by connecting Americans to ideas and each other, in a long and extraordinary career

Source: The Conversation – USA (3) – By Julie Leininger Pycior, Professor of History Emeritus, Manhattan University

“Bill Moyers? He’s spectacular!” George Clooney said – and no wonder.

I mentioned this legendary television journalist to the actor and filmmaker after Clooney emerged from the Broadway theater where he just had been portraying another news icon: Edward R. Murrow. Or as the Museum of Broadcast Communications put it in a tribute to Moyers, he was “one of the few broadcast journalists who might be said to approach the stature of Edward R. Murrow. If Murrow founded broadcast journalism, Moyers significantly extended its traditions.”

Moyers, who died at 91 on June 26, 2025, was among the most acclaimed broadcast journalists of the 20th century. He’s known for TV news shows that exposed the role of big money in politics and episodes that drew attention to unsung defenders of democracy, such as community organizer Ernesto Cortés Jr..

Earlier in his life, Moyers served in significant roles in the Kennedy and Johnson administrations, but his fame comes from his journalism.

Making a connection

Despite his prominence, Moyers was the same down-to-earth guy in person as he seemed to be on the screen. In 1986, he was commanding a television audience of millions, and I was a historian at home with a preschooler, teaching the occasional college course in a dismal job market. Seeing that Moyers would be speaking at the conference on President Lyndon B. Johnson where I would be giving a paper, I wrote to him.

To my utter amazement, he replied and then showed up to hear my paper, on Johnson’s experiences as a young principal of the “Mexican” school in Cotulla, Texas, where he championed his students but also forged links to segregationists. Cotulla was “seminal” to LBJ’s development, Moyers said. In 1993, he recommended me for a grant that helped me finish a book: “LBJ and Mexican Americans: The Paradox of Power.

A few years later, he asked me to head up a project researching the documents related to his time in Johnson’s administration. His memoir of the Johnson years never materialized. Instead, I edited the bestselling ”Moyers on America: A Journalist and His Times.“

Part of what always impressed me about Moyers was his belief that what matters is not how close you are to power, but how close you are to reality.

‘Amazing Grace’

Moyers didn’t just dwell on politics and policy as a journalist. He also delved into the meaning of creativity and the life of the mind. Many of his most moving interviews spotlighted scientists, novelists and other exceptional people.

He was also arguably among the best reporters on the religion beat. Even if it wasn’t always the main focus of his work or what comes to mind for those familiar with his legacy, still, he was a lifelong spiritual seeker.

This is hardly surprising: Moyers had degrees in both divinity and journalism. As a young man, he briefly served as a Baptist minister.

He once told me that his favorite of the many programs that he produced was the PBS documentary ”Amazing Grace.“ It featured inspiring renditions of this popular Christian hymn as performed by country legend Johnny Cash, folk icon Judy Collins, opera diva Jessye Norman and other musical geniuses. As they share with Moyers their personal connections to this song of redemption, he draws viewers into the stirring saga of its creator, John Newton: a slave trader who became an abolitionist through “amazing grace.”

Bill Moyers interviews Judy Collins about singing ‘Amazing Grace,’ following the production of his PBS special about the hymn.

Life’s ultimate questions

This appreciation of the ineffable clearly informed Moyers’ blockbuster TV series exploring life’s ultimate questions, “Joseph Campbell and the Power of Myth.”

His interviews with Campbell, a comparative mythologist, evoked moments that made time stand still, and this reminded me of Thomas Merton, the American monk and poet, writing, “Everything is emptiness and everything is compassion” on beholding the immense Polonnaruwa Buddhas of Sri Lanka.

To my surprise, Moyers knew about this Trappist monk, telling me, “I always wished that I could have interviewed Merton,” who died in 1968.

It turned out that Moyers had been introduced to Merton by Sargent Shriver, founding director of the Peace Corps, where Moyers was a founding organizer and the deputy director.

Mentored by LBJ

Moyers characterized his Peace Corps years as the most rewarding of his life. When Johnson, his mentor, became president, he asked Moyers to join the White House staff. Moyers turned down the offer, so Johnson made it a presidential command.

The wunderkind – Moyers was 29 years old in 1963, when Johnson was sworn in after President John F. Kennedy’s assassination – coordinated the White House task forces that created the largest number of legislative proposals in American history. Among the programs and landmark reforms established and passed during the Johnson administration were Medicare and Medicaid, a landmark immigration law, the Freedom of Information Act, the Public Broadcasting Act and two historic civil rights laws.

Johnson’s war on poverty, in addition, introduced several path-breaking programs, such as Head Start.

Moyers served as one of Johnson’s speechwriters and was a top official in Johnson’s 1964 presidential campaign. The following year, the Johnson administration began escalating U.S. involvement in the Vietnam War and Johnson named a new press secretary: Bill Moyers. Again, the young man tried to decline, but the president prevailed.

As Moyers had feared, he could not serve two masters – journalists and his boss – especially as the administration’s Vietnam War policies became increasingly unpopular.

LBJ speaks with a young man with dark-rimmed glasses who is wearing a 1960s-style suit and skinny tie.
President Lyndon B. Johnson confers with Bill Moyers, his press secretary, in 1965.
Corbis Historical via Getty Images

Appreciating the world around you

Moyers left the Johnson administration in 1967, turning to journalism. He became the publisher of Newsday, a Long Island, New York, newspaper, before becoming a producer and commentator at CBS News. His commentaries reached tens of millions of viewers, but the network refused to provide a regular time slot for his documentaries. He had previously worked at PBS. In 1987, he decamped there for good.

Moyers’ programs won many journalism awards, including over 30 Emmys, along with the Lifetime Emmy for news and documentary productions.

He helped millions of Americans appreciate the world around them. As he reflected in 2023, in one of the last interviews he gave, to PBS journalist Judy Woodruff at the Library of Congress: “Everything is linked, and if you can find that nerve that connects us to other things and other places and other ideas – and television should be doing it all the time – we’d be a better democracy.”

Judy Woodruff interviews Bill Moyers about his life’s work in government and the media, including his contributions to the launch of PBS, at the Library of Congress.

Today, with disinformation metastasizing, professional journalists losing their jobs by the thousands and some newspaper owners muzzling their editorial staff, thoughtful explanations can lose out. That means Americans can lose out.

“It takes time, commitment” to dig below the surface and discover the deeper meaning of people’s lives, Moyers noted. He sought to understand, for example, why so many folks in his own hometown of Marshall, Texas, have become much more suspicious – resentful, even – of outsiders than when he gave these folks voice in his poignant, prize-winning 1984 program Marshall, Texas; Marshall, Texas.

In this era of growing threats to democracy, what can a young person do who aspires to follow in Bill Moyers’ footsteps – whether in journalism or public life?

Woodruff asked Moyers that question, to which he responded: “You can’t quit. You can’t get out of the boat! Find a place that gives you a sense of being, gives you a sense of mission, gives you a sense of participation.”

Today, with the future of journalism – and of democracy itself – at stake, I think it would help everyone to take to heart the insights of this late, great American journalist.

The Conversation

Julie Leininger Pycior edited the book “Moyers on America: A Journalist and His Times.” She also was hired by Moyers to direct the 18-month “LBJ Years” research project.

In addtion, she served as an unpaid, informal historical adviser for some of his public television programs.

ref. Bill Moyers’ journalism strengthened democracy by connecting Americans to ideas and each other, in a long and extraordinary career – https://theconversation.com/bill-moyers-journalism-strengthened-democracy-by-connecting-americans-to-ideas-and-each-other-in-a-long-and-extraordinary-career-260047

Israël–Iran : la guerre économique a déjà un vainqueur

Source: The Conversation – France in French (3) – By Djamchid Assadi, Professeur associé au département « Digital Management », Burgundy School of Business

Alors qu’un cessez-le-feu, fragile et incertain, est entré en vigueur entre la République islamique d’Iran et Israël, une autre guerre, moins visible mais tout aussi décisive, gagne en intensité : la guerre économique. Car, au-delà des frappes et des missiles, ce sont les finances publiques, la stabilité monétaire et la résilience industrielle qui façonnent les rapports de force.


Le 20 juin, les États-Unis frappent le site de Fordo, une installation hautement sécurisée construite à flanc de montagne près de Qom, conçue pour résister à d’éventuels bombardements. Ce site incarne l’avancée clandestine du programme nucléaire iranien et sa destruction – inachevée selon plusieurs sources –marque une nouvelle étape dans l’escalade militaire entre Israël et la République islamique d’Iran (RII).

Les guerres ne se décident pas seulement sur le terrain militaire. Elles reposent sur les capacités économiques des États qui les mènent. Une armée peut tirer, avancer, frapper, seulement si son pays peut financer ses armes, entretenir ses troupes, réparer ses infrastructures et maintenir sa cohésion interne. Sans ressources, sans capacité de production et sans marge budgétaire, l’effort de guerre s’effondre, quelle que soit la stratégie militaire.

C’est ce que plusieurs économistes, issus de traditions intellectuelles variées, ont souligné avec force. Kenneth Boulding affirmait dès 1962 qu’un pays économiquement affaibli voit sa puissance militaire s’éroder mécaniquement. Duncan Weldon rappelle que les Alliés ont gagné la Seconde Guerre mondiale non seulement sur le front, mais surtout par leur supériorité industrielle. Brigitte Granville, dans What Ails France ?, montre comment les déséquilibres macroéconomiques prolongés fragilisent la souveraineté de l’État. Mark Harrison quant à lui insiste sur le lien entre puissance économique, capacité étatique et efficacité stratégique. J. Bradford DeLong, enfin, observe que les régimes autoritaires du XXe siècle ont souvent été défaits non pas par manque de volonté politique, mais par l’incapacité structurelle de leurs économies à soutenir une guerre prolongée.

Tous ces travaux convergent vers un même enseignement : la force militaire dépend de la solidité économique. Une économie dégradée limite les capacités d’armement, désorganise les chaînes logistiques, fragilise la mobilisation de la population – et réduit, in fine, les chances de victoire.

Dans cette perspective, et au-delà du verdict militaire encore incertain, une question s’impose dès aujourd’hui : dans le conflit ouvert entre Israël et la RII le 13 juin 2025 et interrompu 12 jours plus tard par un cessez-le-feu fragile et incertain qui ne garantit point l’apaisement des tensions, qui gagne la guerre économique – celle qui conditionne toute victoire sur le terrain ?

État des forces économiques des belligérants au seuil de la guerre

Lorsque la guerre éclate le 13 juin 2025, l’économie de l’Iran est déjà exsangue. Selon le FMI, sa croissance réelle du PIB pour l’année est estimée à seulement 0,3 %, contre 3,7 % pour Israël au premier trimestre.

Le chômage illustre également ce déséquilibre. En 2024, il atteint 9,2 % en Iran, chiffre bien en-deçà de la réalité, contre un taux contenu entre 3,0 et 3,5 % en Israël. Ce différentiel traduit une dynamique socio-économique défavorable pour la République islamique, dont la population appauvrie est bien moins mobilisable dans la durée.

L’inflation accentue encore cette asymétrie. Elle est projetée à 43,3 % en Iran contre seulement 3,1 % en Israël. L’érosion rapide du pouvoir d’achat rend la mobilisation sociale difficile à maintenir pour le régime, tant sur le plan logistique que politique.

Côté finances publiques, le déficit budgétaire iranien atteint 6 % du PIB, alourdi par des subventions ciblées et des dépenses idéologiques. Israël, de son côté, parvient à contenir son déficit à 4,9 %, malgré une forte hausse des dépenses militaires. Là encore, le contraste signale une dissymétrie stratégique structurelle.

La situation monétaire renforce ce déséquilibre. Le rial s’est effondré, passant de 32 000 IRR/USD en 2018 à près de 930 000 IRR/USD en 2025. À l’inverse, le shekel reste stable autour de 3,57 ILS/USD. Une monnaie stable permet à Israël de maintenir ses importations critiques et de financer son effort de guerre dans des conditions soutenables. La RII, au contraire, voit sa capacité de financement militaire minée par une défiance monétaire généralisée.

Enfin, l’ouverture économique creuse davantage l’écart. L’Iran reste largement isolé du système financier international, frappé par les sanctions et déserté par les investisseurs étrangers, évoluant ainsi dans une autarcie contrainte. Israël bénéficie au contraire d’une intégration industrielle et technologique consolidée par ses alliances stratégiques.

Au total, la République islamique d’Iran entre dans le conflit dans une position structurellement défavorable : faible croissance, inflation galopante, déficit public incontrôlé, monnaie en chute libre, isolement économique, et population précarisée mécontente. Israël s’engage quant à lui avec un socle économique solide, des indicateurs de résilience et une profondeur stratégique qui lui permettent d’envisager un effort militaire prolongé.

Le coût quotidien de la guerre : une pression inégale sur les économies

Le conflit entre Israël et la RII s’est caractérisé par des campagnes aériennes intensives, des bombardements ciblés, des tirs de missiles longue portée et des cyberattaques. Les frappes israéliennes ont prioritairement visé des infrastructures militaires et logistiques.

Les dépenses engagées sont considérables : munitions guidées, missiles, drones, avions de chasse, radars, systèmes antiaériens, dispositifs de guerre électronique, salaires et primes militaires, ainsi que toute la logistique liée au front. Selon le Middle East Monitor, s’appuyant sur des données relayées par le Wall Street Journal, le coût quotidien du conflit s’élèverait à environ 200 millions de dollars pour Israël.

Pour la RII, aucune estimation indépendante n’est disponible à ce jour dans des sources reconnues. Toutefois, certains observateurs avancent, sans vérification rigoureuse, une fourchette allant de 150 à 200 millions de dollars par jour. Cette hypothèse doit être prise avec prudence, en l’absence de sources publiques confirmées.

Mais ces montants, similaires en valeur absolue, n’ont pas du tout le même poids économique selon les pays. Leurs effets, leur soutenabilité et leur impact sur la durée dépendent directement de la structure et de la santé économique de chaque État. Là où Israël peut absorber le choc, l’Iran semble déjà en tension.

Financer la guerre : entre ressources disponibles et épuisement des leviers

Israël soutient son effort de guerre grâce à un environnement financier solide, un accès complet aux marchés internationaux et un tissu productif performant. Il bénéficie aussi d’un appui logistique et stratégique direct des États-Unis (ravitaillements, batteries THAAD, intercepteurs, présence navale) et de renforts britanniques. L’OECD Economic Survey : Israel 2025 conclut qu’Israël conserve une stabilité macroéconomique robuste malgré les tensions géopolitiques.

La RII, en revanche, reste privée d’aide bilatérale et exclue des marchés de capitaux. Son financement de guerre repose sur :

1) Des exportations pétrolières résiduelles ;

2) Un endettement intérieur via des bons du trésor ;

3) Des collectes informelles religieuses (ṣadaqa maḏhabī, naḏr o niyāz) depuis l’été 2025.

Dans le budget 2025, l’augmentation des crédits alloués aux Gardiens de la Révolution et aux entités religieuses dépasse 35 %, tandis que les salaires publics grimpent de 18 à 20 %, dans un contexte d’inflation estimée à plus de 40 %. Ainsi, l’Iran oriente ses ressources vers la survie idéologique plutôt que la soutenabilité économique à long terme.

Conclusion : l’Iran mène la guerre dans une fragilité croissante – sans marges fiscales, sans soutien extérieur et dans un climat de défiance généralisée – tandis qu’Israël conserve pour l’heure une capacité d’action durable.

Une asymétrie stratégique à portée systémique

À l’issue de cette analyse, un constat s’impose : Israël est en train de remporter la guerre économique, indépendamment de l’évolution militaire immédiate.

Le pays s’appuie sur des alliances solides, des marges budgétaires substantielles et un environnement financier stable qui lui permettent de soutenir son effort de guerre dans la durée. Ce socle est consolidé par un soutien logistique et diplomatique direct des États-Unis – et, dans une moindre mesure, du Royaume-Uni – qui étend sa profondeur stratégique bien au-delà de ses frontières.

La République islamique d’Iran, en revanche, mène ce conflit dans un isolement quasi total, sans appui extérieur et avec des ressources internes de plus en plus fragiles : exportations pétrolières limitées, endettement intérieur peu soutenable, captation de fonds religieux. Cette situation ne reflète pas seulement deux modèles économiques distincts, mais deux trajectoires institutionnelles divergentes, désormais soumises à l’épreuve d’une guerre prolongée.

L’histoire récente – de la Yougoslavie des années 1990 à la Russie de 1917, en passant par l’Allemagne impériale en 1918 ou la Syrie après 2012 – montre que l’effondrement économique peut précipiter la défaite, même sans effondrement militaire immédiat.

Dès lors, la question centrale devient celle de la soutenabilité. La République islamique d’Iran peut-elle poursuivre son engagement militaire sans déclencher de ruptures budgétaires, monétaires ou sociales ? Israël, malgré sa solidité, pourra-t-il maintenir le soutien de sa population dans le cas d’un enlisement ou d’un choc stratégique externe ?

Dans ce face-à-face, l’économie ne joue pas un rôle secondaire. Elle est le révélateur du déséquilibre stratégique – et peut-être, à terme, le facteur décisif du basculement. Une stratégie comparable à la « guerre des étoiles » de Reagan, qui avait épuisé l’URSS en l’entraînant dans une course aux dépenses militaires insoutenables, semble aujourd’hui appliquée à la République islamique d’Iran.

The Conversation

Djamchid Assadi 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. Israël–Iran : la guerre économique a déjà un vainqueur – https://theconversation.com/israel-iran-la-guerre-economique-a-deja-un-vainqueur-259627

In LGBTQ+ storybook case, Supreme Court handed a win to parental rights, raising tough questions for educators

Source: The Conversation – USA (3) – By Charles J. Russo, Joseph Panzer Chair in Education and Research Professor of Law, University of Dayton

The parents who brought the case had requested that their children be excused when books with LGBTQ+ characters were used in class. SDI Productions/E+ via Getty Images

The Supreme Court tends to save its blockbuster orders for the last day of the term – and 2025 was no exception.

Among the important decisions handed down June 27, 2025, was Mahmoud v. Taylor – a case of particular interest to me, because I teach education law. Mahmoud, I believe, may become one of the court’s most consequential rulings on parental rights.

An interfaith coalition of Muslim, Orthodox Christian and Catholic parents in Montgomery County, Maryland – including Tamer Mahmoud, for whom the case is named – questioned the school board’s refusal to allow them to opt their young children out of lessons using picture books with LGBTQ+ characters. Ruling in favor of the parents, the court found that the board violated their First Amendment right to the free exercise of religion by requiring their children to sit through lessons with materials inconsistent with their faiths.

Case history

The parents in Mahmoud challenged the use of certain storybooks that the board had approved for use in preschool and elementary school. “Pride Puppy!” for example – a book the schools later removed – portrays a family whose pet gets lost at a LGBTQ+ Pride parade, with each page devoted to a letter of the alphabet. The book’s “search and find” list of words directs readers to look for terms in the pictures, including “(drag) queen” and “king,” “leather” and “lip ring.” Other materials included stories about same-sex marriage, a transgender child, and nonbinary bathroom signs.

Initially, school administrators agreed to allow opt-outs for students whose parents objected to the materials. A day later, however, educators changed their minds. School officials cited concerns about absenteeism, the feasibility of accommodating opt-out requests, and a desire to avoid stigmatizing LGBTQ+ students or families.

In August 2023, a federal trial court rejected the parents’ claim that officials had violated their fundamental due process right to direct the care, custody and education of their children. The following year, the U.S. Court of Appeals for the 4th Circuit affirmed in favor of the board, finding that officials did not violate the parents’ rights to the free exercise of their religious beliefs, as protected by the First Amendment.

A protest outside, with people walking down a street as they carry placards.
A group of parents in Montgomery County, Maryland, protest the lack of opt-outs on July 20, 2023.
Celal Gunes/Anadolu Agency via Getty Images

On appeal, a 6-3 Supreme Court reversed in favor of the parents. Justice Samuel Alito, who authored the court’s opinion, was joined by Chief Justice John Roberts, plus Justices Clarence Thomas, Neil Gorsuch, Brett Kavanaugh and Amy Coney Barrett.

Supreme Court

In brief, the court held that by denying the parental requests to opt their children out of instruction inconsistent with their beliefs, school officials violated their First Amendment right to the free exercise of religion.

Alito largely grounded the court’s rationale in a dispute from 1925, Pierce v. Society of Sisters of the Holy Name of Jesus and Mary, and even more heavily on 1972’s Wisconsin v. Yoder. Both cases recognize the primacy of parental rights to direct the education of their children. According to Pierce’s famous dictum, “the child is not the mere creature of the state; those who nurture him and direct his destiny have the right, coupled with the high duty, to recognize and prepare him for additional obligations.”

In Yoder, Amish parents – an Anabaptist Christian community that avoids using many modern technologies – objected to sending their children to school after eighth grade because this would have violated their religious beliefs. The justices unanimously agreed with the parents that their children received all of the education they needed in their communities. The justices added that requiring the children to attend high school would have violated the parents’ rights to direct their children’s religious upbringing.

Accordingly, the court acknowledged that the parental right “to guide the religious future and education of their children” was “established beyond debate.”

Similarly, in Mahmoud the court declared that “the Board’s introduction of the ‘LGBTQ+-inclusive’ storybooks, along with its decision to withhold opt-outs, places an unconstitutional burden on the parents’ rights to the free exercise of their religion.”

Thomas agreed fully with the court, yet wrote a separate concurrence, which emphasized “an important implication of this decision for schools across the country.” Citing Yoder, Thomas contended that rather than support inclusion, the board’s policy “imposes conformity with a view that undermines parents’ religious beliefs, and thus interferes with the parents’ right to ‘direct the religious upbringing of their children.’”

Justice Sonia Sotomayor’s dissent, joined by Justices Elena Kagan and Ketanji Brown Jackson, feared “the result will be chaos for this Nation’s public schools. Requiring schools to provide advance notice and the chance to opt out of every lesson plan or story time that might implicate a parent’s religious beliefs will impose impossible administrative burdens on schools.”

A handful of people stand outside holding placards with messages including 'Read with pride not prejudice.'
Supporters of LGBTQ+ rights demonstrate outside the U.S. Supreme Court during oral arguments in Mahmoud v. Taylor on April 22, 2025.
Oliver Contreras/AFP via Getty Images

She maintained that “simply being exposed to beliefs contrary to your own” does not violate a person’s free exercise rights. Insulating children from different ideas, she wrote, denies them of an experience that is crucial for democracy: “practice living in our multicultural society.”

Implications

After the decision was handed down, Montgomery County’s Board of Education issued a statement promising to “analyze the Supreme Court decision and develop next steps in alignment with today’s decision, and as importantly, our values.”

Mahmoud raises challenging questions about the scope or reach of how far parents can question curricular content.

On the one hand, parents should not be able to micromanage curricular content via the “heckler’s veto,” because this can lead to larger issues. Moreover, while Mahmoud concerns religious rights, what happens if parents question teachings based on another type of sincerely held belief – discussing war if they are pacifist, for example, or capitalism if they are socialists? While Mahmoud dealt with free-exercise rights, it may open the door to other types of First Amendment challenges from parents wishing to exempt their children from lessons.

On the other hand, Mahmoud highlights the need to take legitimate parental concerns into consideration. While educators typically control instruction, how can they be respectful of parents’ rights as primary caregivers of their children when conflicts arise?

Mahmoud may go a long way in defining parents’ free-exercise rights in public schools. Still, such disputes are likely far from over in America’s increasingly diverse religious culture.

The Conversation

Charles J. Russo 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. In LGBTQ+ storybook case, Supreme Court handed a win to parental rights, raising tough questions for educators – https://theconversation.com/in-lgbtq-storybook-case-supreme-court-handed-a-win-to-parental-rights-raising-tough-questions-for-educators-260064

1 in 4 Americans reject evolution, a century after the Scopes monkey trial spotlighted the clash between science and religion

Source: The Conversation – USA (3) – By William Trollinger, Professor of History, University of Dayton

The 1925 Scopes trial, in which a Dayton, Tennessee, teacher was charged with violating state law by teaching biological evolution, was one of the earliest and most iconic conflicts in America’s ongoing culture war.

Charles Darwin’s “Origin of Species,” published in 1859, and subsequent scientific research made the case that humans and other animals evolved from earlier species over millions of years. Many late-19th-century American Protestants had little problem accommodating Darwin’s ideas – which became mainstream biology – with their religious commitments.

But that was not the case with all Christians, especially conservative evangelicals, who held that the Bible is inerrant – without error – and factually accurate in all that it has to say, including when it speaks on history and science.

The Scopes trial occurred July 10-21, 1925. Between 150 and 200 reporters swooped into the small town. Broadcast on Chicago’s WGN, it was the first trial to be aired live over radio in the United States.

One hundred years after the trial, and as we have documented in our scholarly work, the culture war over evolution and creationism remains strong – and yet, when it comes to creationism, much has also changed.

The trial

In May 1919, over 6,000 conservative Protestants gathered in Philadelphia to create, under the leadership of Baptist firebrand William Bell Riley, the World’s Christian Fundamentals Association, or WCFA.

Holding to biblical inerrancy, these “fundamentalists” believed in the creation account detailed in chapter 1 of Genesis, in which God brought all life into being in six days. But most of these fundamentalists also accepted mainstream geology, which held that the Earth was millions of years old. Squaring a literal understanding of Genesis with an old Earth, they embraced either the “day-age theory” – that each Genesis day was actually a long period of time – or the “gap theory,” in which there was a huge gap of time before the six 24-hour days of creation.

This nascent fundamentalist movement initiated a campaign to pressure state legislatures to prohibit public schools from teaching evolution. One of these states was Tennessee, which in 1925 passed the Butler Act. This law made it illegal for public schoolteachers “to teach any theory that denies the story of divine creation of man as taught in the Bible, and to teach instead that man has descended from a lower order of animals.”

The American Civil Liberties Union persuaded John Thomas Scopes, a young science teacher in Dayton, Tennessee, to challenge the law in court. The WCFA sprang into action, successfully persuading William Jennings Bryan – populist politician and outspoken fundamentalist – to assist the prosecution. In response, the ACLU hired famous attorney Clarence Darrow to serve on the defense team.

A large group of men and women standing outside, intently looking ahead.
A huge crowd attending the Scopes trial.
Bettmann/Contributor via Getty Images

When the trial started, Dayton civic leaders were thrilled with the opportunity to boost their town. Outside the courtroom there was a carnivalesque atmosphere, with musicians, preachers, concession stands and even monkeys.

Inside the courtroom, the trial became a verbal duel between Bryan and Darrow regarding science and religion. But as the judge narrowed the proceedings to whether or not Scopes violated the law – a point that the defense readily admitted – it seemed clear that Scopes would be found guilty. Many of the reporters thus went home.

But the trial’s most memorable episode was yet to come. On July 20, Darrow successfully provoked Bryan to take the witness stand as a Bible expert. Due to the huge crowd and suffocating heat, the judge moved the trial outdoors.

The 3,000 or so spectators witnessed Darrow’s interrogation of Bryan, which was primarily intended to make Bryan and fundamentalism appear foolish and ignorant. Most significant, Darrow’s questions revealed that, despite Bryan’s’ assertion that he read the Bible literally, Bryan actually understood the six days of Genesis not as 24-hour days, but as six long and indeterminate periods of time.

A man in a white shirt and black bow tie stands with arms outstretched while talking, while others seated in rows around him look on.
American lawyer and politician William Jennings Bryan during the Scopes trial in Dayton, Tenn.
Hulton Archive/Getty Image

The very next day, the jury found Scopes guilty and fined him US$100. Riley and the fundamentalists cheered the verdict as a triumph for the Bible and morality.

The fundamentalists and ‘The Genesis Flood’

But very soon that sense of triumph faded, partly because of news stories that portrayed fundamentalists as ignorant rural bigots. In one such example, a prominent journalist, H. L. Mencken, wrote in a Baltimore Sun column that the Scopes trial “serves notice on the country that Neanderthal man is organizing in these forlorn backwaters of the land.”

The media ridicule encouraged many scholars and journalists to conclude that creationism and fundamentalism would soon disappear from American culture. But that prediction did not come to pass.

Instead, fundamentalists, including WCFA leader Riley, seemed all the more determined to redouble their efforts at the grassroots level.

But as Darrow’s interrogation of Bryan made obvious, it was not easy to square a literal reading of the Bible – including the six-day creation outlined in Genesis – with a scientific belief in an old Earth. What fundamentalists needed was a science that supported the idea of a young Earth.

In their 1961 book, “The Genesis Flood: The Biblical Record and its Scientific Implications, fundamentalists John Whitcomb, a theologian, and Henry Morris, a hydraulic engineer, provided just such a scientific explanation. Making use, without attribution, of the writings of Seventh-day Adventist geologist George McCready Price, Whitcomb and Morris made the case that Noah’s global flood lasted one year and created the geological strata and mountain ranges that made the Earth seem ancient.

“The Genesis Flood” and its version of flood geology remains ubiquitous among fundamentalists and other conservative Protestants.

Young Earth creationism

Today, opinion polls reveal that roughly one-quarter of all Americans are adherents of this newer strand of creationism, which rejects both mainstream geology as well as mainstream biology.

A large wooden ship resting on the ground with people walking nearby.
Replica of Noah’s Ark at the Ark Encounter, near Williamstown, Ky.
Ron Buskirk/UCG/Universal Images Group via Getty Images

This popular embrace of young Earth creationism also explains the success of Answers in Genesis – AiG – which is the world’s largest creationist organization, with a website that attracts millions of visitors every year.

AiG’s tourist sites – the Creation Museum in Petersburg, Kentucky, and the Ark Encounter in Williamstown, Kentucky – have attracted millions of visitors since their opening in 2007 and 2016. Additional AiG sites are planned for Branson, Missouri, and Pigeon Forge, Tennessee.

Presented as a replica of Noah’s Ark, the Ark Encounter is a gigantic structure – 510 feet long, 85 feet wide, 51 feet high. It includes representations of animal cages as well as plush living quarters for the eight human beings who, according to Genesis chapters 6-8, survived the global flood. Hundreds of placards in the Ark make the case for a young Earth and a global flood that created the geological strata and formations we see today.

Ark Encounter has been the beneficiary of millions of dollars from state and local governments.

Besides AiG tourist sites, there is also an ever-expanding network of fundamentalist schools and homeschools that present young Earth creationism as true science. These schools use textbooks from publishers such as Abeka Books, Accelerated Christian Education and Bob Jones University Press.

The Scopes trial involved what could and could not be taught in public schools regarding creation and evolution. Today, this discussion also involves private schools, given that there are now at least 15 states that have universal private school choice programs, in which families can use taxpayer-funded education money to pay for private schooling and homeschooling.

In 1921, William Bell Riley admonished his opponents that they should “cease from shoveling in dirt on living men,” for the fundamentalists “refuse to be buried.” A century later, the funeral for fundamentalism and creationism seems a long way off.

The Conversation

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

ref. 1 in 4 Americans reject evolution, a century after the Scopes monkey trial spotlighted the clash between science and religion – https://theconversation.com/1-in-4-americans-reject-evolution-a-century-after-the-scopes-monkey-trial-spotlighted-the-clash-between-science-and-religion-258163

Pop, soda or coke? The fizzy history behind America’s favorite linguistic debate

Source: The Conversation – USA (2) – By Valerie M. Fridland, Professor of Linguistics, University of Nevada, Reno

‘I’ll have a coke – no, not Coca-Cola, Sprite.’ Justin Sullivan/Getty Images

With burgers sizzling and classic rock thumping, many Americans revel in summer cookouts – at least until that wayward cousin asks for a “pop” in soda country, or even worse, a “coke” when they actually want a Sprite.

Few American linguistic debates have bubbled quite as long and effervescently as the one over whether a generic soft drink should be called a soda, pop or coke.

The word you use generally boils down to where you’re from: Midwesterners enjoy a good pop, while soda is tops in the North and far West. Southerners, long the cultural mavericks, don’t bat an eyelash asking for coke – lowercase – before homing in on exactly the type they want: Perhaps a root beer or a Coke, uppercase.

As a linguist who studies American dialects, I’m less interested in this regional divide and far more fascinated by the unexpected history behind how a fizzy “health” drink from the early 1800s spawned the modern soft drink’s many names and iterations.

Bubbles, anyone?

Foods and drinks with wellness benefits might seem like a modern phenomenon, but the urge to create drinks with medicinal properties inspired what might be called a soda revolution in the 1800s.

Drawing of hexogonal soda fountain with three visible spouts.
An 1878 engraving of a soda fountain.
Smith Collection/Gado via Getty Images

The process of carbonating water was first discovered in the late 1700s. By the early 1800s, this carbonated water had become popular as a health drink and was often referred to as “soda water.” The word “soda” likely came from “sodium,” since these drinks often contained salts, which were then believed to have healing properties.

Given its alleged curative effects for health issues such as indigestion, pharmacists sold soda water at soda fountains, innovative devices that created carbonated water to be sold by the glass. A chemistry professor, Benjamin Stillman, set up the first such device in a drugstore in New Haven, Connecticut, in 1806. Its eventual success inspired a boom of soda fountains in drugstores and health spas.

By the mid-1800s, pharmacists were creating unique root-, fruit- and herb-infused concoctions, such as sassafras-based root beer, at their soda fountains, often marketing them as cures for everything from fatigue to foul moods.

These flavored, sweetened versions gave rise to the linking of the word “soda” with a sweetened carbonated beverage, as opposed to simple, carbonated water.

Seltzer – today’s popular term for such sparkling water – was around, too. But it was used only for the naturally carbonated mineral water from the German town Nieder-Selters. Unlike Perrier, sourced similarly from a specific spring in France, seltzer made the leap to becoming a generic term for fizzy water.

Black and white photo of the interior of a drug store, with various health remedies sold on the right side, and a soda fountain with stools on the left.
Many late-19th-century and early 20th-century drugstores contained soda fountains – a nod to the original belief that the sugary, bubbly drink possessed medicinal qualities.
Hall of Electrical History Foundation/Corbis via Getty Images

Regional naming patterns

So how did “soda” come to be called so many different things in different places?

It all stems from a mix of economic enterprise and linguistic ingenuity.

The popularity of “soda” in the Northeast likely reflects the soda fountain’s longer history in the region. Since a lot of Americans living in the Northeast migrated to California in the mid-to-late 1800s, the name likely traveled west with them.

As for the Midwestern preference for “pop” – well, the earliest American use of the term to refer to a sparkling beverage appeared in the 1840s in the name of a flavored version called “ginger pop.” Such ginger-flavored pop, though, was around in Britain by 1816, since a Newcastle songbook is where you can first see it used in text. The “pop” seems to be onomatopoeic for the noise made when the cork was released from the bottle before drinking.

A jingle for Faygo touts the company’s ‘red pop.’

Linguists don’t fully know why “pop” became so popular in the Midwest. But one theory links it to a Michigan bottling company, Feigenson Brothers Bottling Works – today known as Faygo Beverages – that used “pop” in the name of the sodas they marketed and sold. Another theory suggests that because bottles were more common in the region, soda drinkers were more likely to hear the “pop” sound than in the Northeast, where soda fountains reigned.

As for using coke generically, the first Coca-Cola was served in 1886 by Dr. John Pemberton, a pharmacist at Jacobs’ Pharmacy in Atlanta and the founder of the company. In the 1900s, the Coca-Cola company tried to stamp out the use of “Coke” for “Coca-Cola.” But that ship had already sailed. Since Coca-Cola originated and was overwhelmingly popular in the South, its generic use grew out of the fact that people almost always asked for “Coke.”

Advertisement for orange soda reading 'a soft drink made from real oranges.'
No alcohol means not ‘hard’ but ‘soft.’
Nostalgic Collections/eBay

As with Jell-O, Kleenex, Band-Aids and seltzer, it became a generic term.

What’s soft about it?

Speaking of soft drinks, what’s up with that term?

It was originally used to distinguish all nonalcoholic drinks from “hard drinks,” or beverages containing spirits.

Interestingly, the original Coca-Cola formula included wine – resembling a type of alcoholic “health” drink popular overseas, Vin Mariani. But Pemberton went on to develop a “soft” version a few years later to be sold as a medicinal drink.

Due to the growing popularity of soda water concoctions, eventually “soft drink” came to mean only such sweetened carbonated beverages, a linguistic testament to America’s enduring love affair with sugar and bubbles.

With the average American guzzling almost 40 gallons per year, you can call it whatever you what. Just don’t call it healthy.

The Conversation

Valerie M. Fridland 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. Pop, soda or coke? The fizzy history behind America’s favorite linguistic debate – https://theconversation.com/pop-soda-or-coke-the-fizzy-history-behind-americas-favorite-linguistic-debate-259114

The first fossil thrips in Africa: this tiny insect pest met its end in a volcanic lake 90 million years ago

Source: The Conversation – Africa (2) – By Sandiso Mnguni, Honorary Research Associate, University of the Witwatersrand

The fossil thrips discovered in the Orapa Diamond Mine. Dr Sandiso Mnguni, CC BY-NC-ND

Thrips are tiny insects – their sizes range between 0.5mm and 15mm in length and many are shorter than 5mm. But the damage they cause to crops is anything but small. A 2021 research paper found that in Indonesia “the damage to red chilli plants caused by thrips infestation ranges now from 20% to 80%”. In India, various thrips infestations in the late 2010s and early 2020s “damaged 40%-85% of chilli pepper crops in Karnataka, Andhra Pradesh and Telangana”.

In Africa, a number of thrips species feed on sugarcane and have been known to damage nearly 30% of the crop in a single hectare of a farm. High rates of destruction have been recorded in Tanzania and Uganda on onion and tomato crops.

Now it’s emerged that thrips are hardly new to the African continent and the southern hemisphere more broadly. South Africa’s first and only Black palaeoentomologist, Sandiso Mnguni, who studies fossil insects, recently described a fossil thrips from Orapa Diamond Mine in Botswana that’s more than 90 million years old. He discussed his unique fossil find with The Conversation Africa.

What are thrips and how do they cause damage?

Thrips, also known as thunderflies, thunderbugs or thunderblights, are small, slender and fragile insects. They can be identified by their typically narrow, strap-like, fringed and feathery wings. Over time, they have also evolved distinctive asymmetrical rasping-sucking mouthparts consisting of a labrum, labium, maxillary stylets and left mandible. Most species use these to feed primarily on fungi. Some feed on plants and eat the tender parts of certain crops like sugarcane, tomatoes, pepper, onions, avocado, legumes and citrus fruits, focusing on the buds, flowers and young leaves.

This, along with their habit of accidentally distributing fungal spores while feeding or hunting, makes them destructive crop pests. They tend to feed as a group in large numbers, causing distinctive silver or bronze scarring on the surfaces of stems or leaves.

However, not all thrips are harmful. A small fraction of the 6,500 species that have already been described so far are pollinators of flowering plants; and a handful are predators or natural enemies of moths and other smaller animals such as mites.

A green leaf dotted with small black bugs in held in a person's hand
Larva, pupa and adult Weeping fig thrips (Gynaikothrips uzeli)
fcafotodigital

Tell us about the fossil thrips you’ve discovered

This is the first time that a fossil thrips has been recorded anywhere in Africa – or the entire southern hemisphere.

The Orapa Diamond Mine in Botswana is one of the most important fossil deposits on the continent. It’s about 90 million years old, dating back to the Cretaceous period.




Read more:
Fossil beetles found in a Botswana diamond mine help us to reconstruct the distant past


The deposit is situated 960 metres above sea level in the Kalahari Desert, about 250km due west of Francistown in Botswana, and 824km away from Johannesburg in South Africa. It was first discovered in 1967 and started producing carat diamonds in 1971.

Roughly 90 million years go, steam and gas caused a double eruption of diamondiferous kimberlites. These are vertical, deep-source volcanic pipes that form when magma rapidly rises from the Earth’s mantle, carrying diamonds and other minerals up to the surface. They create a distinctive rock formation that gets studied by geologists. This explosive volcanic eruption formed a deep crater lake at the centre of the mine.

Mining excavations during the 1980s and earlier uncovered and exposed fine-grained sedimentary rocks containing well preserved fossil plants and insects. These have already been studied by many researchers in the past. At the time, geology and palaeontology researchers from what was then the Bernard Price Institute, which has since been renamed the Evolutionary Studies Institute, at the University of the Witwatersrand in Johannesburg, were invited to collect the fossil material.

Although some of the material has been studied in the past, the fossil thrips hadn’t yet been put under the microscope. And that’s just what we did. By using its body characteristics and comparing it to living thrips, we can say for sure that it’s a thrips. But we didn’t give it a formal scientific name because it doesn’t have enough characteristics to classify it at the species level and describe it either as a new species or one that still exists today.

We think that the thrips either flew into the palaeolake that was formed by the volcanic eruption or was transported there through grass from a bird’s nest.

Why is this useful to know?

This discovery sheds light on the biodiversity and biogeography of thrips and many other groups of insects during a time when we know flowering plants that heavily relied on insect pollination were rapidly diversifying. This plant-insect reciprocal interaction goes back to the Devonian period, a time when there was a large super-continent called Gondwana. That’s when the first land plants evolved and dominated the Earth, and inadvertently led to many groups of insects, including thrips, diversifying to keep up with drastic changes in their preferred plant diets and habitats due to the dramatic environmental and climatic changes.




Read more:
Fossil insects help to reconstruct the past: how I ended up studying them (and you can too)


The fossil find also contributes to a more accurate documentation of life on Earth during the Cretaceous and helps scientists in reconstructing the past environment and climate in Botswana.

Hopefully there are more fossil insects waiting to be discovered in Botswana and elsewhere in Africa, to keep improving our picture of this long-ago world, and preserve the heritage of our continent.

The Conversation

Sandiso Mnguni receives funding from the GENUS: DSTI-NRF Centre of Excellence in Palaeosciences (Grant 86073). He is affiliated with the Agricultural Research Council Plant Health and Protection (ARC-PHP) and the Sophumelela Youth Development Programme (SYDP).

ref. The first fossil thrips in Africa: this tiny insect pest met its end in a volcanic lake 90 million years ago – https://theconversation.com/the-first-fossil-thrips-in-africa-this-tiny-insect-pest-met-its-end-in-a-volcanic-lake-90-million-years-ago-249077

Dinosaur tracks, made 140 million years ago, have been found for the first time in South Africa’s Western Cape

Source: The Conversation – Africa (2) – By Guy Plint, Professor Emeritus, Earth Sciences, Western University

Guy Plint examines one of the dinosaur tracks, which is above his head. Annemarie Plint, CC BY-NC-ND

Dinosaurs have captured people’s imagination ever since their bones and teeth were first scientifically described in 1822 by geologist and palaeontologist Gideon Mantell in England.

Dinosaur bones have taught us a great deal about these animals from the “age of dinosaurs”, the Mesozoic Era, which stretched from approximately 252 million years ago to 65 million years ago. However, there’s something especially appealing about a different kind of dinosaur fossil: their tracks, which show researchers what the animals were doing while they were alive.

Ichnology is the study of tracks and traces and, since 2008, the Cape South Coast Ichnology Project has documented more than 370 vertebrate tracksites on South Africa’s southern coast. These sites are from the Pleistocene Epoch, which stretched from approximately 2.6 million years ago to 11,700 years ago, much more recent than the Mesozoic.

We knew that this coastline contained Mesozoic sedimentary rocks, some of which include non-marine sediments that could potentially preserve dinosaur tracks. We are both familiar with dinosaur tracks from our research in Canada, so we decided to investigate the possibility of tracks in South Africa’s Western Cape.

We found some – and, once we knew what to look for, it was evident that the tracks were not rare. In a new paper published in the journal Ichnos, we describe our findings in detail, presenting evidence of tracks of sauropods (enormous plant-eating dinosaurs) and possibly ornithopods (another group of large herbivorous dinosaurs).

The tracks were found in a rugged, remote, breathtakingly spectacular coastal setting. They were made by dinosaurs in a variety of estuarine settings. Some were walking on sandy, inter-tidal channel bars. Others walked on the bottom of tidal channels, their feet sinking down into soft mud forming the bed of the channel. Other vague “squishy” structures were formed by dinosaurs wading, or even wallowing in the muddy fill of abandoned channels.

These tracks are around 140 million years old, from the very beginning of the Cretaceous period when the African and South American tectonic plates were starting to pull apart. Southern Africa has an extensive record of Mesozoic vertebrate fossils, but that record ends at around 180 million years ago in the Early Jurassic with the eruption of voluminous lava flows. To the best of our knowledge, all the southern African dinosaur tracks known until now are from the Triassic and Jurassic periods, so they pre-date these eruptions.

That means these tracks are not only the first from the Western Cape. They also appear to be the youngest – that is, the most recent – thus far reported from southern Africa.

Knowing where to look

After deciding to hunt for potential dinosaur tracks, we visited a few likely sites on the Cape south coast in 2022, choosing areas with non-marine deposits of the appropriate age, mostly in the eastern coastal portion of the Western Cape. We found a few promising spots on that visit and, in 2023, undertook a dedicated examination.

Large horizontal bedding surface exposures in this area are very rare. We knew that, if we were to find dinosaur tracks, they would be evident mostly in profile in vertical cliff exposures.




Read more:
Footprints take science a step closer to understanding southern Africa’s dinosaurs


In the public imagination a dinosaur trackway extends across a level surface and toe impressions are visible. Some may also know that the infill of dinosaur tracks can occur on what are today the ceilings of overhangs or cave roofs. However, there are also distinctive features that allow tracks to be identified in profile. That’s because the animals’ footfalls deformed underlying layers in a distinctive manner.

The problem is that other mechanisms, such as earthquakes, are capable of generating broadly similar deformation structures.

The deposits we were examining had probably also been affected by seismic activity. The challenge was for us to differentiate between the two types of deformation.

The Early Cretaceous rocks that we examined had been studied and reported on decades ago, and the deformation structures had been attributed to origins such as earthquakes rather than living organisms. Since then, however, scientists have developed a better appreciation of what dinosaur tracks look like in profile.

After careful examination, our conclusion was straightforward: both dinosaur-generated and earthquake-generated types of deformation were present in the Cretaceous rocks.

A small scale bar set beneath a dark, rocky protuberance
One of the sauropod tracks identified by the researchers. Scale bar is 20 cm.
Guy Plint, CC BY-NC-ND

Further evidence that we were looking at dinosaur tracks comes from the region’s bone fossil record. Cretaceous bone material has been reported from the region, mostly in the Kirkwood area in the Eastern Cape province. Two dinosaur bones have also been reported from the Knysna area in the Western Cape. One of these, a theropod tooth, was found – and correctly identified – by a 13-year-old boy.




Read more:
Dinosaur tracksite in Lesotho: how a wrong turn led to an exciting find


Clearly, dinosaurs were present in the Western Cape area. That means our discovery of ichnological evidence of their presence is not entirely surprising, but it is still extremely exciting.

Keep exploring

Our team plans to keep exploring deposits of suitable age in the region for evidence of more dinosaur tracks. We also hope that our discovery will inspire a new generation of dinosaur trackers to continue the quest and keep exploring.

The Conversation

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

ref. Dinosaur tracks, made 140 million years ago, have been found for the first time in South Africa’s Western Cape – https://theconversation.com/dinosaur-tracks-made-140-million-years-ago-have-been-found-for-the-first-time-in-south-africas-western-cape-250660

Ancient DNA reveals Maghreb communities preserved their culture and genes, even in a time of human migration

Source: The Conversation – Africa (2) – By Giulio Lucarini, Senior Researcher, Institute of Heritage Science, National Research Council (CNR)

Doukanet el Khoutifa, Tunisia, where some of the remains were found. Giulio Lucarini, CC BY-NC-ND

The Neolithic period began in southwest Asia around 12,000 years ago. It marked a major shift in human history as societies transitioned from hunting and gathering to farming. This sparked migrations across Europe and dramatically reshaped the continent’s gene pool.

For a long time, North Africa was seen as a passive participant in this transformation. The dominant narrative suggested that farming economies never fully took root there.

Some studies proposed that North African communities actively resisted agriculture, except perhaps in the Nile Delta and the western Maghreb (modern-day Morocco). They continued to rely on land snails, wild plants, and hunting for survival. Only later, they also began herding domesticated sheep, goats, and cattle, introduced from southwest Asia.

Genetic studies have only recently tested this reconstruction in North Africa. This has never been done in the eastern Maghreb (modern-day Tunisia and eastern Algeria) – until now.

A clearly ancient human skeleton in a grave alongside a scale bar
A burial at one of the study sites, SHM-1 (Hergla) in Tunisia.
Simone Mulazzani, CC BY-NC-ND

As an Africanist archaeologist, I specialise in the study of ancient societies across Mediterranean Africa and the Sahara. My focus is on how humans adapted to their environments and the rise of food production in these regions. I recently conducted research in the eastern Maghreb alongside an international team of archaeologists, geneticists, and physical anthropologists to trace ancient population movements.

Our new study has just been published in Nature. We analysed the ancient genomes (complete DNA sequences) of nine individuals who lived in the eastern Maghreb between 15,000 and 6,000 years ago.

This may seem like a small sample. But, in the field of ancient DNA research, even a few well-preserved genomes can provide significant insights. They serve as reference points for tracing genetic lineages and identifying ancestral connections.

By adding genetic evidence to broader archaeological findings, we reconstructed patterns of population continuity, interaction and change over thousands of years.

Our results were striking. It’s clear from these genomes that some influence from farmers did reach north Africa from across the Mediterranean. But much of the genetic makeup of the eastern Maghreb populations remained rooted in their ancient foraging heritage.

This challenges the long-held narrative about migration into and out of north Africa before and during the Neolithic. It deepens our understanding of the past and highlights the incredible complexity of human movement and cultural exchange.

As we continue to unravel the genetic legacy of our ancestors, studies like this remind us of the complexity of human history. They show that the history of agriculture in the Mediterranean was not merely one of population replacement. Rather, it was a tale of cultural exchange, adaptation and continuity.

And researching these ancient human movements is more than just a matter of understanding history. It also provides insights into the patterns of migration and adaptation that can help us understand similar processes today.

Extraction and analysis

A map that shows the Mediterranean Sea, the Strait of Sicily and Pantelleria Island
A map of the eastern Maghreb showing the study sites (1: Afalou Bou Rhummel; 2: Djebba; 3: Doukanet el Khoutifa; 4: SHM-1, Hergla)
Giulio Lucarini, CC BY-NC-ND

We worked with ancient genomes extracted from human skeletal remains housed in museum or heritage institution collections. They came from excavations at four sites Afalou Bou Rhummel, Djebba, Doukanet el Khoutifa and SHM-1 (Hergla), all in the eastern Maghreb.

We chose the specimens because they were well-preserved, which is not always the case with ancient DNA.

The analysis found that some of the sampled individuals possessed European farmer ancestry around 7,000 years ago. Europeans contributed some genes to the region – but no more than 20% per individual.

A person working with small bones in a pit alongside some scientific equipment
Excavation of human remains at Doukanet el Khoutifa, Tunisia.
Giulio Lucarini, CC BY-NC-ND

This is a modest genetic influence compared to ancient western Maghreb populations where, at some sites, European farmer ancestry can reach as high as 80%.

Our findings suggest that food-producing economies were introduced to the eastern Maghreb not by a large-scale replacement of the population (as seen in Europe) but more gradually. Change happened through sporadic migrations, mixing of cultures, and the spread of knowledge.

Across sea and land

One of the most intriguing discoveries was the genetic trace of European hunter-gatherers found in one individual from Djebba, Tunisia, dating to around 8,000 years ago. This suggests that early European and north African populations could interact via seafaring routes across the Strait of Sicily.

Researchers have long known that cultural exchange took place across the Mediterranean. We see this from the spread of technologies such as the so-called pressure technique – a method of shaping stone tools by carefully applying force with a pointed implement rather than striking the stone directly.

The discovery in Tunisia of obsidian (volcano glass) from Pantelleria, a small island in the Strait of Sicily, strengthens the link between the Mediterranean’s northern and southern shores.

Prehistoric wooden artefacts are seldom preserved over time. This may explain the absence of boat remains from this period in North Africa. However, dugout canoes from similar periods found in central Italy (Bracciano Lake) suggest that seafaring skills were well established around the Mediterranean. While there is no direct evidence linking these specific canoes to connections between Europe and North Africa, they support the idea that navigation was within the technological capabilities of the time.

Our study is the first time the connections suggested by this existing evidence have been substantiated genetically.




Read more:
Discovery of 5,000-year-old farming society in Morocco fills a major gap in history – north-west Africa was a central player in trade and culture


Another exciting aspect of our study is the identification of early Levantine (modern southwest Asia)-related ancestry in the eastern Maghreb. This was detected in human remains dated to around 6,800 years ago. It’s a genetic signature that postdates the arrival of European farmer ancestry by several centuries. It likely reflects the movement of people associated with early pastoralism, who introduced domesticated animals, such as sheep and goats, to the region.

Backing up archaeological evidence

It is especially rewarding to see the genetic evidence aligning with the archaeological record. This underscores the value of multidisciplinary research in uncovering past human dynamics.

What emerges overall is a region of strong genetic and cultural resilience, consistent with archaeological evidence.

The Conversation

Giulio Lucarini receives funding for this study from the National Research Council of Italy (CNR) and ISMEO – International Association for Mediterranean and Oriental Studies, Italy. He is affiliated with the National Research Council of Italy, Institute of Heritage Science (CNR-ISPC).

This study resulted from a collaboration between the following institutions: Harvard University, USA; the Max Planck Institute, Germany; the National Research Council of Italy (CNR); the Institut National du Patrimoine (INP), Tunisia; the Centre National de Recherche Préhistorique, Anthropologique et Historique (CNRPAH), Algeria; the Institut de Paléontologie Humaine (IPH), France; the University of Vienna, Austria; Sapienza University of Rome, Italy; and ISMEO – International Association for Mediterranean and Oriental Studies, Italy.

ref. Ancient DNA reveals Maghreb communities preserved their culture and genes, even in a time of human migration – https://theconversation.com/ancient-dna-reveals-maghreb-communities-preserved-their-culture-and-genes-even-in-a-time-of-human-migration-248338

Black holes spew out powerful jets that span millions of light-years – we’re trying to understand their whole life cycle

Source: The Conversation – Africa (2) – By Gourab Giri, Postdoctoral researcher, University of Pretoria

An artistic representation of what a giant cosmic jet the size of the distance between the Milky Way and Andromeda could look like. Author provided, CC BY-SA

There is a supermassive black hole at the centre of nearly every big galaxy – including ours, the Milky Way (it’s called Sagittarius A*). Supermassive black holes are the densest objects in the universe, with masses reaching billions of times that of the Sun.

Sometimes a galaxy’s supermassive black hole “wakes up” due to a sudden influx of gas and dust, most likely supplied from a neighbouring galaxy. It begins eating up lots of nearby gas and dust. This isn’t a calm, slow or passive process. As the black hole pulls in material, the material gets superheated on a scale of millions of degrees, far hotter than the surface temperature of our Sun, and is ejected from the galaxy at near-light speeds. This creates powerful jets that look like fountains in the cosmos.

The accelerated high-speed plasma matter prompts these “fountains” to emit radio signals that can only be detected by very powerful radio telescopes. This gives them their name: radio galaxies. While black holes are common, radio galaxies are not. Only between 10% and 20% of all galaxies exhibit this phenomenon.

Giant radio galaxies are even less common. They account for only 5% of all radio galaxies and take their name from the fact that they reach enormous distances. Some radio galaxies’ jets reach nearly 16 million light-years. (That’s almost six times the distance between the Milky Way and the Andromeda galaxy.) The largest jet discovered spans nearly 22 million light-years across.




Read more:
South African telescope discovers a giant galaxy that’s 32 times bigger than Earth’s


But how do these structures cover such enormous distances? To find out, I led a study in which we used modern supercomputers to develop models that simulated behaviour of giant cosmic jets within a mock universe, constructed on the basis of fundamental physical laws governing the cosmos.

This allowed us to observe how radio jets propagate over hundreds of millions of years – a process impossible to track directly in the real universe. These sophisticated simulations provide deeper insights into the life cycle of radio galaxies, highlighting the differences between their early, compact stages and their later, expansive forms.

Understanding the evolution of radio galaxies helps us unravel the broader processes that shape the universe.

Supercomputing

Cutting-edge technology was key to this study.

Sensitive observations from world-class radio telescopes like South Africa’s MeerKAT and LOFAR in the Netherlands have recently led to several discoveries of cosmic fountains.




Read more:
MeerKAT: the South African radio telescope that’s transformed our understanding of the cosmos


However, modelling their origins has been challenging. Tracking events over millions of years is impossible in real-time.

That’s where supercomputers come in. These high-performance computing systems are designed to process massive amounts of data. They can perform complex simulations at incredible speeds. In this study, their power was crucial for modelling the evolution of giant radio jets over millions of years.

The necessary supercomputing power was provided by South Africa’s Inter-University Institute for Data Astronomy, a network comprising the University of Pretoria, the University of Cape Town and the University of the Western Cape.

Our universe is governed by fundamental forces like gravity, which can be described through mathematical formulas. These formulas, essentially numbers, are fed into supercomputers to create a simulated “mock universe” that follows the same physical laws as the real cosmos. This allows scientists to experiment with how jets from supermassive black holes evolve over time. With their immense processing power, supercomputers can simulate millions of years of cosmic jet evolution in just a month.

Key takeaways

Gravity is the dominant force in the universe, pulling heavier matter and dragging nearby lighter matter. If gravity were the only force at play, the universe might have collapsed by now. Yet we see galaxies, galaxy clusters and even life itself thriving. We suspect that these cosmic fountains play a key role in solving the mystery of how this happens.

By releasing thermal and mechanical energy, they heat up the surrounding collapsing gas, counteracting gravity and maintaining a balance that sustains cosmic structures.

Our models also shed light on why some radio galaxies’ jets bend sharply, forming an “X” shape in radio waves instead of following a straight trajectory, and revealed the conditions under which giant fountains can continue growing even in dense cosmic environments (that is, in a galaxy cluster).

The study also suggests that giant radio galaxies may be statistically more common than previously believed. There are potentially thousands of undiscovered giant cosmic fountains. Thanks to world-class telescopes like MeerKAT and LOFAR – and the power of supercomputers – there’s plenty more to explore as we try to understand our universe.

The research on which this article is based required extensive collaboration with an international team, including Jacinta Delhaize from the University of Cape Town, Joydeep Bagchi from Christ University, India, and DJ Saikia from the Inter-University Centre for Astronomy and Astrophysics in India. Essential contributions by Kshitij Thorat and Roger Deane from the University of Pretoria also played a crucial role in shaping the study.

The Conversation

Gourab Giri 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. Black holes spew out powerful jets that span millions of light-years – we’re trying to understand their whole life cycle – https://theconversation.com/black-holes-spew-out-powerful-jets-that-span-millions-of-light-years-were-trying-to-understand-their-whole-life-cycle-250073