Ask the Naked Scientists

Introducing "Smellyvision": this week, we talk about new tech that transmits smells alongside sounds and pictures, and ask whether smell is our most underrated sense. Also, are Bill Gates' fears that AI will erode our intellect well-founded, and why do some worry it might lead to better biological weapons? Meanwhile, how has Jonathan the giant tortoise lived to almost 200, and how long could a human theoretically survive? And why do scientists seem to say one thing one minute, and then change their minds a week later? Dr Chris Smith and Clarence Ford have the answers. Like this podcast? Please help us by supporting the Naked Scientists

Why has everyone got a cold at the moment? How does an elemental diet treat inflammatory bowel disease? How does chlorine clean up drinking water? What is cholera? Can silver sterilise surfaces and water? Is static electricity down to positive or negative charge? What is reverse osmosis water filtering, and why is it controversial? Dr Chris Smith and Clarence Ford have the answers. Like this podcast? Please help us by supporting the Naked Scientists

How do dogs decode human speech? Can they actually understand one another, and do they bark with an accent? Also, do all animals pair for life? Why are biometric fingerprint scanners tricky for older people? And is AI damaging our ability to think for ourselves? Plus, what's the problem with asking AI to solve complex maths puzzles, and can it also help decode what animals are saying? Dr Chris Smith and Clarence Ford have the answers. Like this podcast? Please help us by supporting the Naked Scientists

Who scooped Nobel Prizes at this year's ceremony in Stockholm? How concerned should we be about AI's impact on society? Why do men have larger Adam's apples? How can we make sure we eat a balanced diet? What causes floaters in your eyes? Is the expanding Universe contracting elsewhere? And is there a new fluoride-free toothpaste gel that rebuilds teeth? Dr Chris Smith and Saskia Falken have the answers. Like this podcast? Please help us by supporting the Naked Scientists

Dr Chris Smith and Relebogile Mabotja explore why it's hard to reach a human in customer service. How did humans migrate from Africa, and can we trace our ancient paths? Why do people and animals have different neck sizes? Can you really hear your heartbeat when your head's on the pillow? Why is swimming in cold water easier than taking a cold shower? Why do your ears block when you yawn or blow your nose? Why don't you notice yourself growing? Like this podcast? Please help us by supporting the Naked Scientists

Dr Chris Smith and Clarence Ford discuss the world's hottest creature, why antimatter matters, whether weight-loss pills can cause blindness, and why some birds die when they fly into power cables while others can perch on them with impunity. Then, what are the risks of AI, can curly hair straighten out as we age, and how does hair colour change as we grow up? Plus, whether insects are a good source of protein. Like this podcast? Please help us by supporting the Naked Scientists

Can sensors help keep our roads in good shape? If the Earth is round, why aren't the people at the bottom standing upside down? How efficient is the human body? Why can't periods be controlled like going to the bathroom? Do animals have periods too? Where did water come from in the first place, and why doesn't it go off? Dr Chris Smith and Relebogile Mabotja have the answers. Like this podcast? Please help us by supporting the Naked Scientists

Should we take AI warnings seriously? Do fingernails and hair grow more quickly after they are cut? How does caffeine trick the brain into making us feel less tired? Are high levels of low-density lipoprotein a concern? What is mirror life, and should we be worried? What's the attraction of an electric vehicle? Why is it so excruciating when someone scratches their nails down a chalkboard? Dr Chris Smith and Clarence Ford have the answers. Like this podcast? Please help us by supporting the Naked Scientists

How might technology influence or manipulate the weather? Can aircraft affect the weather? Are we getting better at detecting cancer before it becomes problematic? How does perfect pitch work? And why does our hearing change with age? Does weight have any impact on tides? If medication can reduce HIV to an undetectable level, why is there still no cure? Dr Chris Smith and Saskia Falken have the answers. Like this podcast? Please help us by supporting the Naked Scientists

Why might the shingles vaccine help prevent heart attacks? Does an eclipse affect how we sleep? Why do farts seem to stick around longer in the shower? How does toothpaste fight acidity? Can you train your brain to notice different frequencies? How does the Moon affect the tides? And why is it so much harder to stand on one foot with your eyes closed? Dr Chris Smith and Clarence Ford have the answers. Like this podcast? Please help us by supporting the Naked Scientists