Detta är en ganska vanlig trope. Men här är ett av de bättre kända exemplen:
Enligt Restaurangen i slutet av universet , Jorden var befolkade av den misslösa medelklassen på planeten Golgafrincham, som skickades här på Ark B. Arken var avsiktligt kraschad in i jorden, men tillräckligt med Golgafrinchans överlevde för att bli den dominerande arten på planeten, utplåna den infödda hominider.
The Golgafrinchans are a race of humanoid beings who realised that there were three types of beings on the planet of Golgafrincham. Thinkers, Workers, and the strange Middle Class.
The middle class comprised of hair dressers, lawyers, telephone sanitisers, and other such "worthless jobs".
The Thinkers built a ship and told the third class that the planet was to be consumed by a "giant space goat". So they built a ship and sent off their third class. Telling them that they would follow soon. The Third class ended up on Earth, "mucking up the program to determine the ultimate question", while the rest of the classes were killed off by a raging disease contracted from public telephones. Golgafrincham itself soon after was consumed by a giant space goat.