Why do flies eat poo? Why, when I touch something, do my atoms not merge with the object? Are we living in a computer simulation?
All season we've been trying to answer the top mysteries that have baffled scientists for centuries. Now, we're answering yours! 
Ask a question of your own at FunKidsLive.com/mysteries and you could be in the next season of Mysteries of Science!
This episode might finish Season 3 but it doesn't spell the end of Mysteries of Science.
We'll be back soon and looking at more of the most mind bending stuff in the universe. 
Mysteries of Science is a fortnightly podcast created by The Week Junior's Science+Nature magazine and Fun Kids.
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