Every week The Naked Scientist offers listeners the opportunity to probe his brain on anything weird and quirky.
This week's science story is about the dart frog.
If you have ever wondered why poison dart frogs don't poison themselves, wonder no more. The Naked Scientist explains that Central and South American poison dart frogs are powerfully immune to their own poison.
For thousands of years, indigenous tribes like the Noanamá Chocó and Emberá Chocó in Columbia, have smeared the sharp tips of their blow darts and arrows with secretions from poison dart frog's skin.— Dr Chris Smith, Naked Scientist
These secretions contain chemicals called batrachotoxins, which the animals pick up from the centipedes and other insects that form part of their rainforest diet.— Dr Chris Smith, Naked Scientist
Aside from making a neat evolutionary and biochemical story, discoveries like this matter because they provide new insights into how nerves and muscle cells operate, and highlight novel targets for the development of drugs and other therapeutics adds the Naked Scientist.
Why do people scream when they fall from the highest buildings before hitting the ground?— John, caller
The Naked Scientist there is a range of emotions individual experience when a loss of control is sensed. When we fall, it is a completely foreign and terrifying experience which solicits a bunch of reactions. One of the things human beings do is aim to elicit the help and support of our peers and colleagues around us, that is why we cry, go red and call out for help, he says.
Screaming is one good way to help and alert people to danger because we are very tuned in to the sounds of screams.— Dr Chris Smith, Naked Scientist
The wheels of an airplane, I understand, don't turn when a plane lands but how do the wheels cope with that weight and instant acceleration without bursting or overheating?— Pete, caller
That is because they have been built by very clever engineers who have tested them very carefully. He adds that the wheels have very good bearings and as they touch down the runway, the wheels begin to spin very quickly.
The Naked Scientist also says the wheels do wear out but the designers have built wheels made up of a cluster of tyres, so that if one fails the others can take up the load.
Listen to more of the Naked Scientist in the audio clip below: