At level 22 it evolves into Swellow.
Train Taillow to level 22
Taillow evolves at level 22.
Taillow evolves at Level 22.
A Taillow will evolve arounde level 22.
at level 22.
Level 23. 
level 22
level 22
i think at level 32
22
It evolves into swellow at level 22
level 22