Science Weekly

Back in November, researchers hailed the dawn of a new era of Alzheimer’s therapies. After decades of failure, a clinical trial finally confirmed that a drug, lecanemab, was able to slow cognitive decline in patients with early stages of the disease. The result may have been modest – a reduction in the decline in patients’ overall mental skills by 27% over 18 months – but it could not be more significant in the journey towards better understanding and treating the disease. Ian Sample speaks to Prof Nick Fox about the clinical trial results, if this could be the first of many new Alzheimer’s therapies, and whether we could one day see a cure.. Help support our independent journalism at theguardian.com/sciencepod

From a fragment of skull in a washing machine to a finger bone found by a dog walker, the forensic anthropologist Prof Dame Sue Black has helped solve many strange and mysterious cases. This year, she will be giving the Royal Institution Christmas lectures, Britain’s most prestigious public science lectures. In them, she’ll be investigating the secret clues hidden in our bodies and how the scientific detective process can be used to identify the living and the dead. Nicola Davis sat down with Black to discuss the lectures, her most memorable cases, and why she didn’t want her daughters to get braces. Madeleine Finlay hears from them both in this Christmas special of Science Weekly. Help support our independent journalism at theguardian.com/sciencepod

As Christmas approaches, many of us will have spent the last few weeks trying to pick out the perfect presents for friends, family and colleagues. For both giver and receiver, exchanging gifts can be filled with delight – or dread, as a smile slowly fades into a look of feigned enthusiasm. But what does science say about how to avoid unwanted gifts and unpleasant surprises? Ian Sample speaks to Julian Givi about his research unwrapping what we all actually want under the tree, and hears his top tips for choosing a winning present every time. Help support our independent journalism at theguardian.com/sciencepod

A historic deal has been struck at the UN’s biodiversity conference, Cop15, which will set a course for nature recovery from now until 2050, including a target to protect 30% of the planet for nature by the end of the decade. One of the key phrases guiding the summit across the two weeks of negotiations was ‘nature positive’. Madeleine Finlay hears from the biodiversity reporter Phoebe Weston about what ‘nature positive’ meant at Cop15, and what she’d like to see from countries now the final agreement has been made, and speaks to biodiversity professor EJ Milner-Gulland about how to stop the term ‘nature positive’ becoming another way for companies to greenwash their businesses.. Help support our independent journalism at theguardian.com/sciencepod

This week, researchers at the US National Ignition Facility in California achieved a major breakthrough in nuclear fusion. For the first time, humans have harnessed the process that powers the stars to generate more energy from a fusion reaction than was used to start it — otherwise known as ‘ignition’. But how close are we to moving this from laboratories to power plants, and will it become the clean, safe, and abundant source of energy the world so desperately needs? Ian Sample speaks to Alain Bécoulet about what’s being called ‘one of the most impressive scientific feats of the 21st century’. Help support our independent journalism at theguardian.com/sciencepod

Invasive non-native species are on the rise around the world and, despite efforts to tackle the issue, their numbers are higher than ever. They have become one of the key driving forces behind biodiversity loss, posing an even greater threat to biodiversity than the climate crisis. Monitoring, tracking and managing invasive species is one of the issues up for discussion at the UN’s biodiversity Cop15, which is now in full swing in Montreal, Canada. Ian Sample gets an update on how Cop15 is progressing from biodiversity and environment reporter Patrick Greenfield, and hears from Prof Helen Roy from the UK Centre for Ecology & Hydrology about why invasive species pose such a serious risk to native wildlife. Help support our independent journalism at theguardian.com/sciencepod

Negotiators from around the world have landed in Montreal, Canada for the UN’s biodiversity conference, Cop15. The summit has been called an “unprecedented” opportunity for turning the tide on nature loss and comes at a critical time: a million species are at risk of extinction and wildlife populations have plunged by an average of 69% between 1970 and 2018. Madeleine Finlay speaks to the director of science at the Royal Botanic Gardens, Kew, Prof Alexandre Antonelli, about the current state of the planet’s biodiversity, what needs to be achieved at Cop15 and how he’s feeling about the possibility of change.. Help support our independent journalism at theguardian.com/sciencepod

The UK Health Security Agency issued a rare alert on Friday, telling parents to look out for signs of strep A infection in their children. Since September, eight children in England and Wales have died after becoming unwell with Group A streptococci bacteria. Typically causing illnesses like skin infections, tonsillitis or scarlet fever, very occasionally strep A can become a life-threatening, invasive disease. But why are we seeing such a steep rise in cases in the UK this year? Madeleine Finlay speaks to Chrissie Jones, associate professor of paediatric infection at the University of Southampton, about the significance of this outbreak and the symptoms to be aware of, and asks Shiranee Sriskandan, professor of infectious diseases at Imperial College London, about how the bacteria can evade our immune systems and whether we may one day have a vaccine.. Help support our independent journalism at theguardian.com/sciencepod

The UK is in the middle of its worst outbreak of bird flu. The current strain of H5N1 avian influenza has devastated wild bird populations, killing thousands and affecting threatened species such as puffins and hen harriers. Bird flu has also been wreaking havoc on poultry, and since 7 November, all captive birds in England have been kept indoors to prevent them catching the virus. How are both wild and captive bird populations coping with the current strain of avian flu? And is the UK prepared to deal with another major animal disease outbreak? Ian Sample speaks with Phoebe Weston, a biodiversity writer for the Guardian, and Paul Wigley, a professor in animal microbial ecosystems at the University of Bristol.. Help support our independent journalism at theguardian.com/sciencepod

At a recent conference in France, scientists and government representatives voted to scrap the leap second by 2035. Leap seconds are added periodically to synchronise atomic time and astronomical time, which get out of sync because of variations in the Earth’s rotation. Madeleine Finlay speaks to JT Janssen, the chief scientist at NPL, the National Physical Laboratory, about the differences between these two times, and what can go wrong when leap seconds are added to our clocks. Help support our independent journalism at theguardian.com/sciencepod