Disease, death, or other health-related outcomes are then ascertained and compared. common source outbreak: An outbreak that results from a group of persons being exposed to a common noxious influence, such as an infectious agent or toxin.
Pokedex Entry #041: Zubat is a Poison/Flying Type Pokemon. It evolves into Golbat. Zubat remains quietly unmoving in a dark spot during the bright daylight hours. It does so because prolonged exposure to the sun causes its body to become slightly burned.
For example if you had a level 8 Zubat evolved it into a Golbat at level 22 and leveled it up to level 44 there would be a high chance for it to evolve but this is only an example, it varies. Another way is to use rare candies, poffins, and pokeblocks.