Melissa Majoria
Melissa Majoria was the homeworld of bees, some of which made their way to Earth. In 2009, the bees sensed that a catastrophe was about to befall the Earth, and began to make their way back to Melissa Majoria. Donna Noble noticed this several times, and remarked on it to the Doctor, who also found it odd. (DW: Partners in Crime, Planet of the Ood)
The catastrophe was Davros moving the Earth to the Medusa Cascade. The bees' movement created a disturbance on the Tandoka scale, which allowed the Doctor and Donna to trace their path towards the Earth. (DW: The Stolen Earth)
Behind the Scenes
Melissa Majoria is not to be confused with Miasimia Goria, a planet ruled over by the Rani (DW: The Mark of the Rani).
This is similar to the dolphins returning to their home planet in The Hitchhiker's Guide to the Galaxy.
