Evolution/Overview

Evolution is not a merely visual change, as Pokémon of a higher evolutionary stage have different (and usually more powerful) base stats than their predecessors, may have different moves that can be learned, and sometimes change their types, though usually at least one of the types of the previous form is preserved. Other statistics, such as Nature and s, as well as, are preserved. The Pokémon's Ability slot also remains the same, though depending on species, the actual Ability may change. With respect to real-world phenomena, Pokémon Evolution is more similar to than. Evolution also appears to be a mostly independent phenomena from the process for most species, though Baby Pokémon need to evolve to their next stage in order to breed.

Professor Elm and Professor Rowan are the leading experts in Pokémon Evolution. According to the latter's research, over 90% of all Pokémon are connected to at least one other through Evolution (this is true only if Legendary Pokémon are excluded). Rowan's research in Generation IV regards whether Evolution is a form of maturity in Pokémon, and looking at the implications of the process on Legendary Pokémon, which at that time did not evolve.