The science of going viral: Expert explains how memes compete, reproduce and evolve just like genes

As you went about your day quietly humming it, perhaps someone else heard you and complained minutes later that you'd gotten the tune stuck in their head. The song's hook seems to have the ability to jump from one brain to another. And perhaps, to jump from the web browser you are using right now to your brain. In fact, you may be singing the hook to yourself right now. Something similar happens on the internet when things go viral – seeming to follow no rhyme or reason, people are compelled to like, share, retweet or participate in things online.