This week's science question: Why do cats purr?
Cats purr to express contentment. What Bob REALLY meant to ask was HOW cats purr.
Cats purr when air escapes through their vocal folks and oscillates, which causes a vibration. That sound is actually too low for us to hear, but the movement causes other parts of their throats to vibrate, and that produces the sound that we hear.
And our winner this week is Vanessa Mckillop of Halifax