Ask the Naked Scientists

What gases are present in lava? What happens when hot magma meets cold water in the sea? How different is an animal's brain to my own? How much of my intelligence is down to genes, and how much is the environment in which I grew up? Do photons weigh anything? Is there a cancer pandemic? And will a spoon in the neck of the bottle keep champagne fizzy? Dr Chris and Lester Kiewit tackle your burning questions... Like this podcast? Please help us by supporting the Naked Scientists

This week, James Croll and Mulitun Milankovic's contributions to planetary climate cycles; what it takes to knock a planet off-axis; where do clouds falling off Table Mountain go; does a discharged battery weigh less than a charged battery; the cheese reaction and bad dreams; why some foods go through undigested; why are planets round; birds recognising their own flocks; Captain Kirk heads to space; is a bad smell potentially infectious? Lester Kiewit and Dr Chris have the answers... Like this podcast? Please help us by supporting the Naked Scientists

This week, where Vitamin D comes from, if lab-grown protein is vegan-friendly, how mammals evolved to dive deep underwater, how genes can be used to track evolution, how chillies create a burning sensation in the mouth, whether feet change shape as we age, what makes a battery rechargeable, and why tropical seas tend to be blue and clear. Dr Chris Smith and Lester Kiewit have the answers... Like this podcast? Please help us by supporting the Naked Scientists

What makes a virus mutate? Why does bladder control become so much harder to achieve the closer I get to a toilet? How does sneezing work? How are vaccines quality controlled and assured around the world? What happens to Covid-19 vaccines if the cold-chain is broken? Dr Chris and Africa Melane have the answers... Like this podcast? Please help us by supporting the Naked Scientists

This week it's time to join another local school to answer their burning science questions including can we bring back extinct species from the dead; is the Universe infinite; can we replace cells and tissues in the body; will science solve Alzheimer's Disease; are humans getting taller; how do viruses like Covid-19 evolve and change; why do black holes matter; and, an easy one to finish on: what's consciousness!? Like this podcast? Please help us by supporting the Naked Scientists

What causes r-rolling difficulties otherwise known as rhotacism? Also, why do we have to stay still in an MRI scanner, why is calcium a metal, what makes water hard and how does a water softener work, what is the impact of a caesarian birth on health and why, what's the reason dementia affects short but not long term memory, and how does gravity work? Join Lester and Dr Chris for the answers to this week's crop of questions... Like this podcast? Please help us by supporting the Naked Scientists

This week we ask whether we're about to start spoiling other planets with our space forays, if there is antimatter in the human body, what causes cluster headaches, whether microwaving can ripen avocado, what causes long-sight, how atomic clocks operate, the basis of entropy and thermodynamics, why heat wipes out a magnet, and whether cleaning surfaces is a good idea for combating Covid-19... Like this podcast? Please help us by supporting the Naked Scientists

Is there such a thing as a true circle? Can two light rays collide with one another? What makes the sky look blue? Have aliens ever visited Earth? Will time travel ever be possible? What's the perfect pH for seed germination? Would a truck full of birds weigh less if all the birds took off? What's at the bottom of a black hole? Why is poo brown despite the fact we all eat different foods? This week the questions for Dr Chris come from the kids at Gaia Waldorf School, and they're very hard! Like this podcast? Please help us by supporting the Naked Scientists

Why do I shiver when I wee? How does carbon dating work? What can I not tickle myself - is that similar to why I mind my own farts less than someone else's? Does breath-holding block tickle sensations? How does "the cloud" work in computing? Why are sunsets red, and what is the green flash? Why would a telegraph pole by the road vibrate of its own accord? Dr Chris and Lester have the solutions! Like this podcast? Please help us by supporting the Naked Scientists

Can you be allergic to one part of an animal but not another? What's the point of dreaming? What happened before the Big Bang? What's in wine that causes hangovers, and is this an allergic reaction? Are we seeing into the past when we detect light from far away in space? Why does driving through a long tunnel or across a bridge make me feel giddy? Lester and Dr Chris make your head spin with the answers! Like this podcast? Please help us by supporting the Naked Scientists

How do African animals withstand extreme cold in the Kalahari? Does the data we're all generating and storing weigh anything? How does relativity relate to the real world? Why do we run Olympic races in the direction we do? Is the ozone hole disappearing now? Were left handers less able to defend themselves back in history? Is a germinating seed making new matter? And will volcanoes eventually empty the Earth of magma? Lester and Chris have the answers... Like this podcast? Please help us by supporting the Naked Scientists

Why do some forms of heater seem to warm a room up faster? What's the different between Alzheimer's Disease and dementia? Are aluminium cooking utensils a risk factor for Alzheimer's? Can magic mushrooms control dementia, or other mood disorders? How do we know what's inside the Earth, and did we collide with another planet during Earth's past? Are microwaves a risk for cancer? Is there a limit to human Olympic performance? Like this podcast? Please help us by supporting the Naked Scientists

In this week's show, recorded before the Euro 2021 final, Dr Chris explains why Inuits survive on polar fare with impunity but Shackleton's crew developed nutritional deficiency when they were stuck in the Antarctic. Also, why laser beams are bad for goalkeepers, if energy drinks are dangerous, why squinting sharpens vision, if there humans with better senses than average, and what is meant by the percentage chance of rain? Like this podcast? Please help us by supporting the Naked Scientists

Can electric eels power the national grid? What does 5% alcohol in a beer really mean? Does alcoholic hand cleanser ruin your fingerprints? Why does warm water on cold feet feel scalding hot? Is behaviour genetic - do I inherit my mood from my dad? Join Dr Chris and Azania Mosaka as they unravel the answers... Like this podcast? Please help us by supporting the Naked Scientists

This week, what happened to the Wankel Rotary Engine; why does air become thinner at altitude and thicker at depths; and why do I need to blow my nose vigorously when I first wake up but not at other times of the day? Also, what are the best pollinators, what's the evidence for macro-evolution, why do many great discoveries get discovered at the same time by independent workers, and what happens in the brain during hypnosis. Join Dr Chris and Lester Kiewit for the answers... Like this podcast? Please help us by supporting the Naked Scientists

Which is better, male or female? Why does one nostril sometimes seem to work better than the other? Why do some birds hop but others waddle? What's monosodium glutamate and what does it do to food? Why are other people's farts harder to tolerate? What causes multiple pregnancies? Why do we sometimes feel cold? And why don't professional sportsmen, like tennis players, not end up with one massive dominant arm? Join Dr Chris Smith and Lester Kiewit for the answers... Like this podcast? Please help us by supporting the Naked Scientists

Why might it feel colder at daybreak compared with during the night? What's the best gap between doses for Covid-19 vaccines? What causes albinism and can albinos do anything to make their skin darker? What are stretch marks? And how do bees make honey? Join Dr Chris and Azania Mossaka for the answers... Like this podcast? Please help us by supporting the Naked Scientists

This week how medical detection dogs are sniffing out Covid-19 with 94% success rates, the force powering the expansion of the Universe, how a master key works, whether parallel universes are more fact than fiction, what was Dr Chris's favourite science subject at school, what causes bad dreams, what triggers early labour, and should a Covid-19 recoveree get vaccinated? Like this podcast? Please help us by supporting the Naked Scientists

This week, expiry dates on vaccines, what is a smell and how does the body's olfactory (smelling) system work? Why does the smell of fruits change during the ripening process? Why might sugar on cucumber taste like melon? Do some people inherit genes that mean some smells are inapparent to them? When clouds disappear, where have they gone? How does a cell phone touchscreen work? And why do car exhausts seem to last longer these days? Like this podcast? Please help us by supporting the Naked Scientists

This week, the Covid-19 crisis in India and why it's happening, we discuss why water, despite being replete with hydrogen and oxygen which burn readily, is incombustible, we talk through the safety profile of the coronavirus vaccines, find out why shaking the remote control can apparently bring dead batteries back to life, and touch on the ageing process. We also bid farewell to Kieno, who is departing for pastures new... Like this podcast? Please help us by supporting the Naked Scientists

This week, why it's more comfortable to look at the Sun on the horizon compared with when it's directly overhead, why dogs pee on upright objects, where mosquitoes go in winter, is it normal to have one foot bigger than the other, and what's the best way to breed tall children? Ray White and Chris Smith take on your science questions... Like this podcast? Please help us by supporting the Naked Scientists

If the AZ vaccine causes blood clots, why do affected individuals have low platelets, which should make clotting less likely? Also, when the Earth wobbles on its axis, does the Moon's orbit also change? How many genes of mine will my offspring carry? Could we dump nuclear waste in space? Why do disinfectants claim to kill 99.9% of bugs? Where do they get that number from?! Dr Chris Smith and Azania Mosaka have the answers... Like this podcast? Please help us by supporting the Naked Scientists

Chris Smith and Kieno Kammies discuss the latest on blood clots and Covid-19 vaccines, including the US and South Africa decisions to halt use of the Johnson and Johnson vaccine. Also, are the vaccines a risk for people with aneurysms, what causes recurrent nosebleeds, can we mix flu and coronavirus vaccines, why the heart is so tied up with emotions, and does not having sex harm your health? Like this podcast? Please help us by supporting the Naked Scientists

Should I get vaccinated despite previous Covid-19 infection? Can I get a combined flu and Covid-19 shot? Why can't my pharmacist give me a Covid jab in South Africa? Is a Covid-19 vaccine safe for someone with a history of Guillain-Barre syndrome? Can you find out what Covid-19 variant has infected you? Did they really find Jack the Ripper? And why do dogs and cats turn around in circles when they first get into bed? Join Dr Chris Smith and Kieno Kammies for the answers... Like this podcast? Please help us by supporting the Naked Scientists

The people that don't believe Covid-19 is real, how ants smell out sources of food, how soda water makes you burp, a way to banish ants, what would you change about the human body, why masks stop Covid-19 but not smells, and how long is the recovery time from bone fusion surgery? Join Dr Chris Smith and 567 Cape Talk's Kieno Kammies for the answers... Like this podcast? Please help us by supporting the Naked Scientists

Why are the EU posturing around AstraZeneca's Covid-19 vaccine, and what will be the consequences? And if you've already caught coronavirus, should you still get vaccinated if you are already immune? What is ataxia and how can it be treated? What causes rigor mortis and how long does it last? In Covid-19 genetic vaccines, how long does the foreign genetic material persist in the body? Plus why conspiracy theories and misinformation proliferated online are so toxic. Like this podcast? Please help us by supporting the Naked Scientists

Why is the Moon moving away from the Earth, and what would have been the consequence of it being closer to us millions of years ago? Also, why does Covid-19 anosmia stop me smelling Vick's Vapour rub but I can still feel its effects? Do models have more neck bones to account for their longer necks? Why do some people float but others sink in the swimming pool? And how does lightning work: does it travel upwards, downwards, or neither? Like this podcast? Please help us by supporting the Naked Scientists

Why do we fall asleep when we don't want to? Will going without sex harm your health? Why do aircraft resort to black boxes when they could send data to satellites? Why don't brakes overheat and lock on? Can you create a 1 degree angle? And why does Earth look flat for people on the surface when we all know it's not really flat? Join Dr Chris Smith and Talk Radio 702's Azania Mosaka for the answers... Like this podcast? Please help us by supporting the Naked Scientists

Good news on the Covid-19 vaccine front from the UK, why South Africa isn't using AstraZeneca's vaccine, is the Universe under threat from "strangelets", why has evolution not solved the ageing problem, why ice sticks to an empty glass, the PCR test for Covid-19, and how to stop cats killing wildlife... Like this podcast? Please help us by supporting the Naked Scientists

Will loud music deafen my dog? Why are some dog breeds more docile than others? Why do Covid-19 outbreaks follow cycles of boom and bust? What gives a person their "second wind"? Why do ants invade my kettle and other electronic devices ? Is ant invasion in you home a sign that the place is dirty? Why have I got vibration sensations in my foot? Join Dr Chris Smith and 567 Cape Talk's Saskia Falken to find out... Like this podcast? Please help us by supporting the Naked Scientists

This week we talk vaccines for Covid-19, especially the Novavax trial results, and hear why it might be possible to tune into radio waves with your teeth. We also discuss Covid and cytokine storms, bubbles in the Milky Way, where the sharks go during a tsunami and how radioactivity is used to power spacecraft... Like this podcast? Please help us by supporting the Naked Scientists

This week, Dr Chris and Kieno Kammies talk Covid-19 vaccinations, explore whether ivermectin might be a helpful coronavirus drug, explain how maggots get into wounds, unpick what's in the Covid-19 vaccine, and talk nanoparticles... Like this podcast? Please help us by supporting the Naked Scientists

This week, journey times to Mars, how stars come by the matter inside them, why some people feel compelled to eat paper, how coronavirus antibody levels correlate with Covid-19 severity, whether water really goes down the drain in different directions on opposite sides of the Earth, and why a yawn produces a spray of saliva. Join Dr Chris Smith and Azania Mosaka for the answers. Like this podcast? Please help us by supporting the Naked Scientists

This week, Aza catches coronavirus, Covid-19 vaccines, viral variants and where are the mutations in the SARS-CoV-2 genome, can you still swallow when you're upside down, how was Einstein proved right, and what causes cramp? Dr Chris Smith has the answers... Like this podcast? Please help us by supporting the Naked Scientists

How do energy drinks give you a buzz? Why do planets orbit on a plane? Should we test for Covid-19 infection before we vaccinate? Do energy drinks cause diabetes? Why do you float on the Dead Sea? How does the Plimsoll Line on a boat work? When does Covid infectivity cease after death? What's your first and last organ to die? How do planets orbit? And what's the best way to get rid of rat poison? Join Dr Chris Smith for all the answers... Like this podcast? Please help us by supporting the Naked Scientists

How do point of care tests for Covid-19 work? Are they any good? How infectious are people asymptomatically infected with Covid-19? Why do different car indicators flash at different rates? How do accents work and where do they come from? How many Earths could fit inside Jupiter, and what is the "giant red spot"? Does wearing a facemask have any negative health impacts? Do hailstorms only happen in the daytime? Join Dr Chris Smith and Tshego Modisane for the answers... Like this podcast? Please help us by supporting the Naked Scientists

An update on the Pfizer vaccine for Covid-19, the lotto likelihood of sequential winning numbers, why swallows congregate around motorway bridges, the logistics of keeping the Covid-19 vaccine cold, and why is it dark in space? Also, why is there a Covid-19 vaccine in 10 months but no HIV vaccine after 4 decades, would we still have tides without the Moon, and why is the Moon white since the sky is blue? Join Dr Chris and 567 CapeTalk's Kieno Kammies for the answers... Like this podcast? Please help us by supporting the Naked Scientists

Why shear a sheep in winter when it's cold? And can animals count? Why do geese and turkeys chase people? Also, how does coronavirus infection alter our sense of smell and taste? How do artificial sweeteners work? And when it comes to survival of the fittest, what constitutes "the fittest"? What brings asteroids onto a collision course with the Earth? Dr Chris joins Kieno Kammies to answer this week's crop of farmyard-inspired - and other - questions... Like this podcast? Please help us by supporting the Naked Scientists

Why did touching something make me taste metal? Also, what's the best liver detox, why does listening to loud music stop a stammer, does music help attention deficit disorder and is sunrise to the south even in the southern hemisphere. We also wonder whether perpetual motion is possible, why the sun can make some people sneeze, why ice cubes sometimes crumble, and how some fruits encourage others to ripen. Join Dr Chris Smith and Kieno Kammies for the answers... Like this podcast? Please help us by supporting the Naked Scientists

Why does my Coke froth up when I add ice? How is an oesophageal stricture treated? Does immunity to other coronaviruses confer immunity to Covid-19? Can cats smell things that are poisonous? Why do athletes place their hands on their hips after exercise? And how do fingers help with heat control. Join Dr Chris Smith and Talk Radio 702 Azania Mossaka for all the answers... Like this podcast? Please help us by supporting the Naked Scientists

This week, why teenagers can feel moody, what causes restless leg syndrome, fidgeting and obesity, Covid-19 genetic risk factors, whether potatoes can prevent night cramps and arthritis, and the effects of Epsom salts. Join Dr Chris Smith and 567 CapeTalk's Kieno Kammies for this week's crop of questions and answers... Like this podcast? Please help us by supporting the Naked Scientists

What's the best way to avoid mosquito bites, and a suggestion that tomatoes ward the insects off. Also, why cookers heat some parts of pans better than others, the mind-over-bladder effect when you really need to go, why generic drugs are no different to named brands, why oil makes a rainbow effect on water, if a previously transplanted kidney could be re-used elsewhere, and the toxicity of ozone. Join Dr Chris Smith and 567 CapeTalk's Koketso Sachane for the answers... Like this podcast? Please help us by supporting the Naked Scientists

Vitamin D for coronavirus? Narcissism and the brain. Why use big dogs as sniffer dogs? Understanding conversations in noisy places, and why that gets harder as we age. Why does my hand itch before I receive money? Is the new coronavirus linked to type I diabetes in children? And attaching significance to coincidence! Join Dr Chris on 567 CapeTalk for all the answers... Like this podcast? Please help us by supporting the Naked Scientists

Can omnivores switch their diets to survive on whatever is available? Would a fat person last longer in a famine? How does serology help in the management of Covid-19? Could we use GM technology to develop a healthy form of tobacco? How and why do chameleons change colour? Why does ice stick to your skin? Why does a shop-bought chicken have tender meat and softer bones? Join Dr Chris Smith and Talk Radio 702's Azania Mossaka for the answers... Like this podcast? Please help us by supporting the Naked Scientists

The virtual reality system for visualising molecules, where Covid-19 came from, what would a brain transplanted individual experience, where did all the dust go when Beirut blew up recently, and why is smoking addictive? Join Dr Chris Smith and Talk Radio 702's Azania Mossaka as they delve into the answers... Like this podcast? Please help us by supporting the Naked Scientists

How a tiny spider can spin so much silk, how the moon's cycle affects human behaviour, the effect of body weight on bone mass, the reason people have consciences, and the way to become a scientist all get discussed this week. Join Dr Chris Smith and Kieno Kammies for the answers... Like this podcast? Please help us by supporting the Naked Scientists

Hyenas everywhere in the Kruger, but why so many? How does the human skeleton respond to changing body weight? Why remove and dump a whale carcass when it would rot down naturally? How long does the Covid-19 coronavirus remain viable in the body? Why is the sky blue? And is there a probiotic answer to body odour? Join Dr Chris Smith and Talk Radio 702's Azania Mosaka to find out the answers... Like this podcast? Please help us by supporting the Naked Scientists

Donald Trump diagnosed with Covid-19, SNP MP Margaret Ferrier takes two trains despite coronavirus infection, and the answers to why toddlers have potbellies? Can free-divers get the bends? How does sunscreen work? What's actually inside a black hole? And why do we itch, and what's the point? Join Dr Chris Smith and Kieno Kammies from 567 CapeTalk as they shoot the scientific breeze... Like this podcast? Please help us by supporting the Naked Scientists

Would a baby exposed to 5 languages from birth learn all of them? Toilet bleach: what's best, thick or thin? Are new varieties of fruits equally good for you? What's the proof for absolute zero? How are radio and TV audiences measured? What causes high pitched sounds in the ear that appear to come from nowhere? Join Chris Smith and Kieno Kammies for the answers... Like this podcast? Please help us by supporting the Naked Scientists

How do different tasks recruit different parts of the brain? What's the story of potential life on Venus? How long to boil the perfect egg? What's homocysteine and how much is a safe level in the blood? How does alcohol in hand sanitiser work? What's the most intelligent animal? Are smartphones changing our brains? And does same sex attraction occur in wild animals as well as humans? Join Dr Chris Smith and Kieno Kammies for the answers... Like this podcast? Please help us by supporting the Naked Scientists