Why does spaghetti break into 3 pieces?

Can we rear people in a germ-free environment? Can you be born with only one kidney? Why does spaghetti always break into 3 pieces? What exactly is temperature? When you add more water to the bath and then pull the plug - what water goes down the drain first, the new or the old? Why do birds live longer than their size would suggest? Like this podcast? Please help us by supporting the Naked Scientists