From the ground breaking and life saving to the wacky and implausible, Dr Karl Kruszelnicki reveals some of the best moments in science.
http://www.abc.net.au/radionational/programs/greatmomentsinscience/
The colour of bird poo
Bird poo is usually coloured white—because of the way birds excrete excess nitrogen. But the poo can sometimes be a different colour—because of their diet. Creatures have evolved three main ways of getting rid of excess nitrogen.