Ask the Naked Scientists

What colour were human ancestors? What does a rocket push against in space to propel itself forward? Why does yawning make me cry? How do bats navigate? Can fuel cells run on alcohol? Why are 90% of people right handed? How genetically related would the children of two sets of identical twins be? Plus, noses grown on foreheads and how rotating antibiotic drugs can prevent bacterial resistance... Like this podcast? Please help us by supporting the Naked Scientists

Why scratch your head if you don't know the answer? What about the Earth made the dinosaurs so big? Why does the Universe spin? Is the Sun seem brighter in the morning than the evening? Are autistic people particularly at home with computers? Why do effervescent tablets fizz only in water? Why do Parkinson's patients sleepwalk without difficulty? Plus, news of a decoy molecule that can treat dwarfism and what earwax has revealed about blue whales... Like this podcast? Please help us by supporting the Naked Scientists

How is an electron microscope tip made to measure 1 atom thick? Why do I sound different on a recording? Why does light slow down in some media? Why is soft water slimy? How do ants home in on my handbag? What makes my eyelids twitch? Plus, how scientists are exploring spider venoms as a source of new insecticides... Like this podcast? Please help us by supporting the Naked Scientists

How do robotic surgeons work? Do diamonds melt? What is heartburn? Can fish see colours, and what should anglers wear? What is brain plasticity? What would happen if an egg were dropped into boiling oil? What causes blushing? Why does holding the antenna of an AM radio improve reception? Like this podcast? Please help us by supporting the Naked Scientists

Is global warming a given? Can olive leaf extracts combat parasites? Is there a fake tanning pill? Why keep gas cylinders upright? How does digital storage work? Does reducing body temperture aid infections? How does the moon cycle affect human behaviour? Like this podcast? Please help us by supporting the Naked Scientists

Why is space dark; do bags of coins deter flies; why don't cats go grey; is GPS or an odometer more accurate; what was the effect of the Med drying up in the past; what does an ice-pack versus a hot-pack do for an injury; how might maternal diabetes affect a baby's future health, and should I let the tap run before drinking any water? Plus, urine-powered electricity supplies... Like this podcast? Please help us by supporting the Naked Scientists

Why are we ticklish? What happens to blood when we die? Why are mechanical hearts hard to make? What's a burb? Can a mushroom crack tarmac? Why do helium balloons fly forwards in the car when I brake? Why does microwaved milk explode when I stir it? Like this podcast? Please help us by supporting the Naked Scientists

Do plants do maths? Has the Internet made us all more intelligent? Why did my milk freeze? Why do my hands get cold, but not my face? How did people realise Earth is round? What's red shifting? Why does squinting make it easier to see things? Why is water unreactive when hydrogen and oxygen are? What makes red shifting happen? Dr Chris answers more top science questions from South Africa... Like this podcast? Please help us by supporting the Naked Scientists

How much ice are glaciers losing annually? What makes eyes itch? Is yoga beneficial to health? How do solar sails work? Do we have dominant feet? Why is a rainbow the shape it is? Plus, news of why breastfeeding could help your offspring to climb the social ladder... Like this podcast? Please help us by supporting the Naked Scientists

Why does yawning produce tears? Why do noses tend to run on a cold day? Is methylated spirit good for mosquito bites? Why do computer screens sometimes produce after-images on your eyes? Can blocking blood vessel growth cause cancers to stall? Is cola good for bloat? Is it really colder just as the sun rises? More top science questions from South Africa, as well as news of how the cornea keeps itself clear of blood vessels... Like this podcast? Please help us by supporting the Naked Scientists