At dawn on October 28, residents of Rio de Janeiro woke to the sound of gunfire. Battles continued throughout the day in the favelas of Alemão and Penha, as police mounted a huge operation targeting the Commando Vermelho, or the Red Command, one of Brazil’s largest organised criminal gangs. In the days that followed, as graphic images showed lines of bodies on the streets, it emerged that at least 115 civilians and four police officers had been killed, making it the most violent police operation...
Nov 06, 2025•28 min
In the 16th century, witches and demons weren’t just for Halloween. People were terrified and preoccupied with them – even kings. In 1590, James VI of Scotland – who was later also crowned James I of England – travelled by sea to Denmark to wed a Danish princess, Anne. On the return journey, the fleet was hit by a terrible storm and one of the ships was lost. James, a pious Protestant who would go on to sponsor the translation of the King James bible, was convinced he’d been the target of witchc...
Oct 30, 2025•24 min
One American company called Strategy owns more than 3% of all bitcoin in existence. In August 2020, its executive chairman, Michael Saylor, pioneered a new business model where publicly listed companies buy cryptocurrency assets to hold on their balance sheet. More than 100 other public companies have since followed Saylor’s lead and become bitcoin treasury companies, together holding more than $114 billion of bitcoin. There’s been a new rush into crypto treasury assets in 2025 following the gen...
Oct 23, 2025•22 min
As one of the birthplaces of the industrial revolution, the River Mersey in northern England is no stranger to pollution flowing into its waters. Now it's got a new problem: monitoring shows the amount of forever chemicals, also known as PFAS, entering the Mersey catchment area is among some of the highest in the world. In this episode we speak to water scientist Patrick Byrne at Liverpool John Moores University in the UK about why so many per- and polyfluoroalkyl substances (PFAS), are still ma...
Oct 16, 2025•24 min
Back in the 1980s, when Shimon Sakaguchi was a young researcher in immunology, he found it difficult to get his research funded. Now, his pioneering work which explains how our immune system knows when and what to attack, has won him a Nobel prize. Sakaguchi, along with American researchers Mary Brunkow and Fred Ramsdell, were jointly awarded the 2025 Nobel prize in physiology or medicine for the work on regulatory T-cells, known as T-regs for short, a special class of immune cells which prevent...
Oct 09, 2025•16 min
As Donald Trump gives oxygen to unproven theories about what might be behind a recent rise in autism cases, experts repeatedly point to the changing nature of how autism is diagnosed and viewed. A key moment in the history of autism diagnosis was the publication in 1994 of a new version of the Diagnostic and Statistical Manual of Mental Disorders. It's a reference book of psychiatric conditions and how to diagnose them, used by psychiatrists and psychologists around the world. In this episode, A...
Oct 02, 2025•27 min
Donald Trump is not letting up pressure on the US Federal Reserve. He's taken efforts to fire one of its governors, all the way up to the US Supreme Court. Trump's clash with the Fed echoes pressure that Richard Nixon put on the central bank in the 1970s to lower interest rates. In this episode, Cristina Bodea , professor of political science at Michigan State University, why that moment – and the inflation spike that followed – became a cautionary tale about what can happen if politicians threa...
Sep 25, 2025•27 min
With France, the UK, Australia and Canada expected to recognise an independent Palestinian state at UN General Assembly in New York, what are the origins of the state they plan to recognise? In this episode, Palestinian-American historian Maha Nassar from the University of Arizona describes the events leading up to the original declaration of Palestinian independence in 1988, including the compromises made within the Palestinian liberation movement. Nassar then traces how we've got to the point ...
Sep 18, 2025•29 min
Police in Australia are continuing a huge manhunt in the mountains for Dezi Freeman, a man accused of killing two police officers and injuring a third in late August. Freeman identifies as a sovereign citizen, someone who believes they aren't subject to the law. In this episode we speak to criminologist Keiran Hardy from Griffith University about the origins of the sovereign citizen movement in the US, how it spread to Australia and was taken up by the self-styled Prince Leonard in the 1970s, an...
Sep 11, 2025•24 min
As China invited world leaders to a vast military parade marking the end of the second world war on September 3, President Xi Jinping said China is "never intimidated by bullies" and would "stand by the right side of history". In a coded message about China's territorial ambitions over Taiwan, Xi added that "the great rejuvenation of the Chinese nation was unstoppable". China and Taiwan both claim their forces bore the true burden of Chinese resistance against Japan during the second world war, ...
Sep 04, 2025•25 min
If you’ve ever experienced a state of creative flow, perhaps when writing, playing music, or even gardening, you’ll know that it feels like everything just clicks into place. But what is actually happening inside the brain? This week, we're re-running an episode first published in June 2024 featuring neuroscientist John Kounios at Drexel University in the US. He scanned the brains of jazz musicians as they were improvising, and revealed the secret ingredients need to achieve a state of creative ...
Aug 28, 2025•22 min
AI is transforming the world around us, offering increased productivity and promising to tackle difficult problems like global warming. But behind the scenes, its environmental costs are mounting. From massive energy use to vast quantities of water required to cool data centres, AI’s footprint is growing fast. So, in an age of water scarcity and climate crisis, can we justify this technological boom? As The Conversation Weekly team takes a production break in August, we're delighted to bring you...
Aug 21, 2025•33 min
Scientists can get animals to do the strangest things. They’ve taught goldfish to drive cars, primates to perform calculations with Arabic numerals and giraffes to do statistical reasoning. But what’s the point? In this episode, biologist Scarlett Howard from Monash University in Australia – who has taught bees to tell the difference between odd and even numbers – defends the importance of these seemingly ecologically irrelevant experiments. She argues that they can help us understand the secret...
Aug 14, 2025•22 min
Countries around the world are meeting in Geneva in August to negotiate a global plastics treaty aimed at curbing plastic pollution. The last round of negotiations failed last November after oil-producing countries refused to sign up to a clause calling for the world to reduce its production of plastics. But how did the world become hooked on plastic in the first place? This week, we're re-running an episode we first aired in January 2025 featuring an interview with Mark Miodownik , professor of...
Aug 07, 2025•29 min
Donald Trump is suing Rupert Murdoch, alongside the Wall Street Journal and Dow Jones and others, for libel after the Journal published an article alleging that Trump once wrote a “bawdy” birthday letter to the convicted sex offender, the late Jeffrey Epstein. Trump is seeking US$10 billion in damages. Trump and Murdoch have a transactional friendship that goes back decades. Despite past tensions, this rupture is something new in a relationship that has continued to serve both men’s interests. I...
Jul 31, 2025•28 min
Israel has never officially confirmed or denied having nuclear weapons and has never signed the nuclear non-proliferation treaty. Instead, even as evidence has emerged about its nuclear capabilities, Israel has maintained a policy of nuclear ambiguity. The origins of this opacity lie in a secret deal forged in a one-on-one meeting between Israeli prime minister, Golda Meir, and the US president, Richard Nixon, at the White House in September 1969. In this episode, we speak to Avner Cohen , profe...
Jul 24, 2025•27 min
The majority of the world’s rechargeable batteries are now made using lithium-ion. Most rely on a combination of different rare earth metals such as cobalt or nickel for their electrodes. But around the world, teams of researchers are looking for alternative – and more sustainable – materials to build the batteries of the future. In this episode, we speak to four battery experts who are testing a variety of potential battery materials about the promises they may offer. Featuring Laurence Hardwic...
Jul 17, 2025•26 min
Across Europe, far-right movements are gaining ground. By normalising nationalist rhetoric and challenging democratic institutions, these parties raise comparisons with former periods of fascism on the continent. Between 1943 and 1945, when Nazi forces occupied northern Italy, ordinary people in towns and villages across the country took up arms against fascism in one of Europe’s largest resistance movements. Now, 80 years later, in many of these same towns, anti-fascist sentiment remains unusua...
Jul 10, 2025•24 min
The language from European leaders was fawning and obsequious. At one point, the head of Nato, Mark Rutte, even called Donald Trump “daddy”. But when the US president left the Nato summit in late June, there was a sigh of relief that he had not made any more angry criticism of the alliance. And after months of American pressure, Nato members agreed to increase their spending on defence to 5% of GDP by 2035. So how did Europe become so unable to defend itself that it was forced to resort to outri...
Jul 03, 2025•31 min
Robert F Kennedy Jr caused controversy in April by promising to find a cause for autism by September. Claims by the new US secretary for health and human services that autism is a “preventable disease” with an environmental cause, contradict a body of research that suggests autism is caused by a combination of genetic and external factors. The US government announced that to support its new research effort into autism it would build a “data platform” involving data on claims, medical records and...
Jun 26, 2025•34 min
Faced with the choice in their daily lives, their work or their politics, why do some people decide to keep quiet, to censor themselves in anticipatory obedience, even if they’re not ordered to do so? In this episode we talk to self-censorship expert Daniel Bar-Tal at Tel Aviv University about what drives people to censor themselves, and its consequences for society. This episode was written and produced by Katie Flood with assistance from Mend Mariwany. Gemma Ware is the executive producer. Sou...
Jun 19, 2025•31 min
As Jaws marks its 50th anniversary, sharks continue to get a bad rap. Film after film portrays them as terrifying hunters, the bane of surfers and swimmers. But in Indonesia, sharks are the hunted. It’s the world’s largest shark-fishing nation, with more species of sharks found in Indonesian waters than in any other country. So Indonesia was the ideal place for conservation scientist Hollie Booth at the University of Oxford to test out a new idea: would paying fishermen to release any sharks and...
Jun 12, 2025•23 min
In October 2021, 136 countries agreed to establish new tax rules requiring large multinational companies to pay at least 15% in corporate tax. Nearly four years later, this ambitious agreement is finally being implemented around the world, but its success faces big challenges. In the second part of The 15% solution, we examine progress towards implementing the Organisation for Economic Cooperation and Development's global tax framework. Featuring Martin Hearson , a research fellow at the Institu...
Jun 06, 2025•22 min
For decades, multinational corporations have used sophisticated strategies to shift profits away from where they do business. As a result, countries around the world lose an estimated US$500 billion annually in unpaid taxes , with developing nations hit particularly hard. In the first episode of The 15% solution , we explore how companies have exploited loopholes in the global tax system. We speak to Annette Alstadsæter , director of the Centre for Tax Research at the Norwegian University of Lif...
Jun 05, 2025•26 min
More than two thirds of guns recovered at Mexican crime scenes originate in the U.S. For decades, Mexico has struggled with staggering levels of gun violence fuelled in large part by weapons trafficked across its northern border. Now an investigation published by The Conversation has arrived at a new estimate of the scale of this illicit gun trade between the U.S. and Mexico in 2022: 135,000 guns. Investigative journalist Sean Campbell and Topher McDougal, a professor of economic development at ...
May 29, 2025•42 min
For much of the 21st century, one theory has dominated research efforts to cure Alzheimer's disease: the amyloid hypothesis. Beta-amyloid is a protein that builds up in clumps, or plaques, in the brains of people with Alzheimer's disease and is linked to their cognitive decline. But in recent years, despite the emergence of a couple of new drugs targeting these plaques, some scientists have begun to doubt the amyloid hypothesis. Donald Weaver , a professor of chemistry at the University of Toron...
May 22, 2025•32 min
Three months after the Trump administration made drastic cuts to its aid agency, USAID, the effects are being felt across the world, particularly in Africa. In this episode we speak to Bright Simons, an African aid expert and visiting senior fellow at ODI Global about where the decimation of US aid leaves the debate about the future of development assistance. This episode of The Conversation Weekly was written and produced by Mend Mariwany and Gemma Ware. Mixing and sound design by Eloise Steven...
May 15, 2025•35 min
Liverpool FC just won the English Premier League. Contributing to their 5-1 victory over Tottenham to seal the title was Mohamed Salah, the Egyptian superstar who is the league's top scorer in the 2024-5 season. We're revisiting an episode that we first ran in December 2022 about research which used Salah to demonstrate how a celebrity footballer who is openly Muslim can help to reduce Islamophobia. Salma Mousa , now an assistant professor of political science at UCLA in the US, talks to us abou...
May 08, 2025•17 min
The Trump administration’s cuts to funding for American universities and research have left many scientists reeling and very worried. At the National Institutes of Health, which has an annual budget of US$47 billion to support medical research both in the U.S. and around the world, nearly 800 grants have been terminated. The administration is considering cutting the overall budget of the NIH by 40% . In this episode, we speak to three scientists, Brady West and Sunghee Lee from the University of...
May 01, 2025•39 min
Few places on earth are immune to the explosion of anti-vaccination conspiracy theories and health disinformation fuelled by the COVID pandemic. But in countries like Brazil, where the disinformation flowed from the very top of government, the problem is even more acute and some people are exploiting the fear of others to make money. In this episode we speak to Ergon Cugler at the Brazilian Institute of Information on Science and Technology about his new research into how peddlers of disinformat...
Apr 24, 2025•27 min
