it depends on the Pokemon that are evolving
It evolves at level 40.
level 37
Level 34
Cherubi evolves into Cherrim at level 25.
mightyena doesn't evolve on Pokemon pearl, he doesn't evolve in any Pokemon game!
evolve snowver at level 40
Buizel evolve at level 26.
IT DOESN'T EVOLVE
level 18
at level 30
level 28
Level 37
level 50
Level 18
Level 20.
at level 14