And how did they learn to do it? Ellie and Emma discuss what tool use actually is and the species that have adapted specific instruments to achieve a desired goal. From Veronika the cow to Jane Goodall we explore how far tool use has come and what the possibilities are for species and tools of the future.

Fact check:

• Research about ravens
• Evidence that humans are better than chimps at solving puzzles
• News about Veronika the cow
• An overview of animals using tools
• News of wolves using tools too
• A mason bee carrying objects as it flies
• A video of fish doing stuff

The battery in electric vehicles makes them much heavier than traditional vehicles. Laura and Jasmin discuss how steel car components can be made lighter to offset this increased weight, what implications that has for other industries, and whether this would make the steel industry more sustainable.

Fact check:

• Some ways that steel car components are made lighter
• Stats about the Nissan Leaf and how it compares to a similar spec car with an internal combustion engine
• How steel makers can use maths to understand how the microstructure affects mechanical properties
• Research using AI to predict mechanical properties based on composition
• More research using AI, this time looking at processing variables during manufacture
• Different generations of high strength steel

Ellie, Antonia and Emma discuss their personal experiences with cold water and the science behind whether there is any benefit in dunking yourself in a chilly loch. They also discuss studies related to sauna usage, if cold showers make any difference, and if the Nordic countries have got the right idea 💡

Fact check:

• Research shows that cold plunges can lead to heart attacks
• A scientific review of winter swimming
• Research on the ideal sauna temperature
• A news article about Wimhoff breathing
• A review of research on saunas and ageing showing that 4-7 saunas a week can decreased the risk of developing Alzheimer's disease

Some gemstones are desired for their sparkle and rarity while others have practical applications in engineering and electronic components. Laura and Antonia look at different ways gems can be made in the lab, how valuable they are and consider how you could potentially make a lot of money from them.

Fact check:

• The composition of sapphire and ruby
• A list of valuable diamonds
• The most expensive lab grow gems
• News about growing bigger gems from small ones already used as jewellery
• A research article on the same thing as above
• Synthetic sapphire
• More on synthetic sapphire
• Yet more on synthetic sapphire, in a YouTube video

Researchers were surprised to find that moss spores germinated after nine months hanging out on the outside of the International Space Station. Ellie and Laura dive into their research and go beyond it to look at why some things survive in space, the benefits of doing this sort of research and what it might mean for a more resilient ecosystem here on Earth.

Fact check:

• News about the space moss
• More news
• The original research article on the space moss
• The basics about radiation in space
• Tardigrades can survive some types of UV radiation
• How tardigrades have a genetic response to repair radiation damage
• The BBC Future article Laura mentions about various experiments on tardigrades

Different nations have different approaches to testing and using chemicals to see how they can cause diseases. Antonia, Laura and Jasmin look at how chemicals are tested for toxicity, how harmful substances are controlled, and whether dose limits are important. They look at asbestos, radioactive substances, and more.

Fact check:

• Manufactured chemicals have led to an increase in childhood disease and shouldn’t automatically be presumed safe
• Safety data sheets for waterproofing spray and household bleach
• A history of bioaccumulation of mercury in fish
• News about banning and restricting sales of fish in some nations in relation to wastewater discharge from the Fukushima-Daichii site
• Statistics on global deaths per year due to asbestos exposure
• Statistics on deaths in the UK from asbestos exposure

And is it a good idea? Laura, Jasmin and Antonia look at various scientific studies on growing crops and raising livestock in fields of solar panels to see what the effects are. They also look at some solar farms that are used in arid regions and the benefits they can have for crops and the environment.

Fact check:

• The random broccoli study
• A study of crop growing in arid regions
• One of the review articles/papers
• The other review article, this one on small ruminants
• The study that reported an improvement in the quality of sheep’s wool

And can we learn to live longer? Ellie, Jasmin and Emma discuss telomeres that form the ends of DNA strands, the long-lived members of the animal world, supplements and products to fight the signs of aging, and even the idea of living forever.