Bird poop that held secrets to the universe
In 1965, two radio astronomists, at Bell Labs in New Jersey were bothered by a background noise — a hum — while mounting a large antenna. It was a sound similar to when you might have bad reception and they thought the culprit was bird poop. Like any good astronomers with their fancy Ivy league PhDs on mind bending theories, they set out to clear bird poop. Alas, to no avail, the noise never went away.
Thank god it didn't because the astronomers soon discovered that the noise was cosmic microwave background radiation that marked the birth of the universe. It was the echo of the universe's explosive birth that finally put Big Bang theory on solid ground and confirmed that the cosmos did indeed grow from a tiny seed — a single point — about 13.8 billion years ago. The two astronomers, Bob Wilson and Arno Penzias, won the 1978 Nobel Prize in physics for their work, sharing the award with Soviet scientist Pyotr Kapitsa.
In a clear stroke of butterfly effect or sheer randomness, bird poop helped unravel the secrets of the universe.
PS. I found out about the bird poop story while reading the Black Swan by Nassim Taleb (my favourite author). Highly, highly recommend Antifragile and The Black Swan written by him.