Naked Scientists Podcast: Ice Core Science, Measles Outbreaks, and the Matter-Antimatter Mystery

Episode overview

The Naked Scientists present a multi topic episode covering the arrival and analysis of ancient Antarctic ice cores at the British Antarctic Survey in Cambridge, measles outbreaks and vaccine uptake, the matter-antimatter asymmetry problem explored at CERN, and a twin study probing whether humor is genetic or environmental. The program weaves in energy policy discussions about small modular nuclear reactors and ends with a listener QOTW and a preview of Naked Night events.

Key insights

• Oldest Antarctic ice cores could reveal climate history up to 1.5 million years back, offering details on transitions between cold and warm periods.
• Measles outbreaks are driven by insufficient herd immunity and vaccine safety concerns; high vaccination coverage (~95%) is essential to stop transmission.
• CP violation measurements at CERN indicate a few percent asymmetry in matter-antimatter decays, hinting at new physics beyond the Standard Model.
• A large twin study challenges the idea that humor is strongly genetic, pointing to environmental factors as the dominant influence.

Ice cores and climate history

The podcast opens with the shipment of an Antarctic ice core to Cambridge, where researchers at the British Antarctic Survey describe why ice cores are valuable records, akin to tree rings, for reconstructing past temperatures and precipitation. The core being studied could be as old as 1.5 million years and is drilled from East Antarctica near Little Dome Sea. Analysts will use continuous flow analysis to melt the ice and channel the liquid into instruments that can reveal chemistry and particulates, shedding light on climate transitions long before modern records. The bubbles trapped in the ice will be essential for reconstructing historic greenhouse gas levels, notably CO2, with the recognition that the current longest ice core record extends back 800,000 years. The discussion also covers how different archives, such as marine sediments, complement ice cores by providing broader timelines, but ice cores uniquely preserve atmospheric greenhouse gas records.

Measles outbreaks and vaccination strategy

The episode then shifts to public health, with UK officials urging measles vaccination after a child death and rising cases in the UK, Europe, and the United States. The host explains how measles, one of the most infectious viruses, requires herd immunity levels around 95% to prevent transmission. The discussion emphasizes the need to address misinformation about vaccine safety and to implement catch up campaigns for those who missed vaccinations. The interview with Michael Marks of the London School of Hygiene and Tropical Medicine highlights why sustaining high coverage is crucial for protecting vulnerable groups, especially young children who are not yet vaccine eligible, and for maintaining herd immunity in communities with mobility and varying uptake.

Matter-antimatter asymmetry and the LHC

The podcast then turns to particle physics, with Ben Allan (Cambridge) explaining the matter-antimatter asymmetry observed in the universe. While equal production of matter and antimatter is expected in the early universe, a tiny residual asymmetry persists, leaving matter as the dominant component. Experiments at CERN are probing this asymmetry by comparing decay rates of matter and antimatter, such as lambda B baryons decaying into protons and kaons versus their antiparticle decays. The results show a few percent asymmetry, which is not currently sufficient to explain the observed cosmic imbalance. The discussion underscores the possibility that the Standard Model is incomplete and that new physics or particles could be responsible, with leptogenesis and heavy right-handed neutrinos proposed as potential mechanisms. The future may require more energetic colliders or cosmic ray observations to test these ideas.

The genetics of humor: twin study

Gil Greengross presents Aberystwyth University findings on humor genetics. A twin study using a large, cross-cultural twin sample examined whether humorability has a genetic basis. Researchers used a cartoon captioning task, scored by multiple judges, to quantify how funny a person is. The key result is that identical twins did not show greater similarity than fraternal twins in humorability, suggesting environmental factors drive differences in humor rather than genetics. The study also notes limitations and the need for replication in diverse cohorts to confirm the conclusion, recognizing humor as a complex trait influenced by daily life and social context beyond scripted tasks.

Energy, technology, and the QOTW

Laurie in France asks about power on submarines and Mars rovers, touching on small modular reactors for civilian energy and the economics of grid-scale deployment. Simon Taylor explains nuclear power, including radioisotope thermoelectric generators used on rovers like curiosity and the potential of SMRs with modular design to reduce costs through mass production. The discussion emphasizes that SMRs face economic challenges and that large fixed costs and standardized components could yield efficiency gains, though scale remains critical for electricity markets and grid reliability.

The program also includes Questions of the Week about AI and greenhouse gas reductions, with discussion about how AI can support environmental outcomes and where potential drawbacks may lie. The host closes by thanking listeners and previewing Naked Night, a new live event designed to connect the global science community in a more interactive format, with details to follow.

Closing and next steps

The Naked Scientists team expresses gratitude for listener support and donations and outlines next week’s focus on data science to improve life in care homes, alongside sponsor acknowledgments.