Dr Karl Podcast

Why do people get tired when driving? Is it possible to drive a fast car upside-down in a long, circular tunnel? Are your chances of surviving a car accident better if you are asleep and you're body is limp?

Why do people rock from side-to-side when they sleep? Plus: are humans the only mammal that suffers morning sickness during pregnancy?; and why can cat fur have different colours along the length of each strand of hair?

Why is it considered a good thing to urinate on lemon trees? Plus: can birth marks be hereditary?; and why do yellow sunglasses make daylight appear brighter?

What happens if you swallow chewing gum? Plus: can a woman's tastebuds change during and after pregnancy?; and can drinking milk cause osteoporosis?

Why does crockery seem to randomly explode? Plus: Is it possible to be allergic to only male furry animals?; and a caller reports the results of his and his partner's female ejaculation tests.

As part of triplej's 'sex week', Dr Karl and Zan Rowe take talkback questions ranging from female 'squirting' to male morning glories and having sex during pregnancy.

When using earbud-style headphones, why does the music's pitch seem lower when they're removed? Is there a way to reduce the effects of jet-lag? Why is it when you are extremely tired that trivial things seem very funny?

Why does your head seem to spin when you lie down if drunk? What are the differences between various cookwares and are any types dangerous? What happens to bullets that are fired into the air?

Previous 'Mornings' presenters drop by to share their favourite Dr Karl moments from the last 30 years on triplej. Plus: Karl's favourite organ; his first comments on radio re-enacted; and the five most-common science questions asked by listeners.

In a special triplej listener talkback, Zan Rowe and Dr Karl discuss the link between mental illness and marijuana use with psychiatrist Dr Matthew Large, from the University of New South Wales.

Does cold storage affect how food metabolises and germinates? Plus: why do some people's eyes squeak when they rub them?; and why can some people make their ears 'crack' when they press them?

Do snipers need to take in to account the Coriolis effect when taking a shot? Plus: what happens if you pee on an electric fence?; and can babies breathe underwater?

Why do some mobile phones ring when they are switched off? And why do many women crave chocolate just before their periods?

Why do wasps survive being frozen? If black is a shade of light, then how does a projector recreate it? Why does cold air clear a foggy windscreen better than warm air?

Do microwave ovens block mobile phone reception? Will vinegar sooth sunburn? How can you 'pop' a yawn?

Can copper pipes be made hard again after they have been overheated then cooled? Why do new tyres sometimes leave a blue mark on the ground? Do sports compression shorts work?

What happens when fruit and vegetables cross-pollinate? Why does my hair appear to grow quicker now I shave my head? Does quantum physics imply the existence of a God?

Why don't scars get dirty the same way as the rest of your skin? Do noise-reducing ear plugs damage your ears if you wear them for too long? Can exercising after drinking alcohol help you sober up more quickly?

How do you get green tomatoes to ripen quickly? Can people on a vegan diet receive the same amount of nutrients as meat-eaters? Can static shocks through headphones be dangerous?

Why do some people get itchy legs when they exercise? Plus: what causes some people's cheeks to swell and tingle while eating cheese? And why is bellybutton fluff always blue?

Why do some people see thousands of tiny spots when they look up at the sky or a bright light? What causes a white rainbow? And is there any science to explain ghosts?

What's it like to live in space for 183 days? NASA astronaut Dr Gregory Chamitoff joins Dr Karl to answer all your space questions.

Why do some people work harder at the gym when they listen to a favourite tune? Plus: why does your stomach rumble when you are hungry? And why do your hands tingle after an orgasm?

Why does a bruised apple taste differently to an unbruised one? Plus: is it possible to evaluate the capacity of the brain in gigabytes? And why does caffeine make you feel sick in the stomach?

Why doesn't the skin around nipples get sunburnt? Would global warming interrupt the Atlantic conveyer current and cause an ice age in the northern hemisphere?