Ask 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'...

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 th...

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...

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 wee...

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! Li...

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 a...

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 emp...

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...

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...

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 i...

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 d...

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 h...

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 exh...

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 depa...

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 Sci...

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 Azani...

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...

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...

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 supportin...

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 con...

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...

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 answer...