It evolves from friendliness
you must catch a very low level zubat at least 8 level and start trasforming it with level until it reches 31. if you have catced a stronger zubat or golbat it will transform at 60 to 76 level
level 35
level 36!!
Electrike evolves at level 26.
u have to trade it
Level 16. He will evove again at Level 36.
Much earlier then that
Doduo evolves into Dodrio at Level 31.
You have to trade it while it is holding the Protector.
Golbat evolves by Friendship
Golbat is a happiness evolution so it can evolve at any level.
lairon evolves into aggron at lvl. 42