Can you solve this riddle?
What's big and furry, and alternates between black and white?
Well, a panda bear does not _alternate_ between black and white, does it? It just _is_ black and white; its colors do not change.
Two of you are on the right track.
Now three of you are on the right track: for it's a bear, but not just any bear. Note by the way that it's a joke-riddle.
Well, yes, Gladys, it is now a dead black bear, as it killed itself when it read your answer during its "black" phase...
No. It was a bipolar bear. I guess my question was unclear.