vulpix - ninetails (it was like, cute little boy fox to big sleek woman fox. wtf?)
It represents the japanese
kitsune. They are born normally colored foxes, and have one tail. They grow tails as they age, probably one tail every 1,000 years. Once the kitsune grows it's ninth tail, it turns a white or beige color or silver. That's why. It's not random at all, and I'd hardly call it dramatic.
psyduck - golduck (small, pudgy and yellow to big, lean and blue?)
Come on now, this isn't
that dramatic. They still share many similar qualities of a duck. The only thing is that they put some of the japanese legend into Golduck's design. (kappa)
poliwhirl - politoed (wtf?)
Does this surprise you? Poliwag and Poliwhirl are simply tadpoles that undergo the evolution of turning into a frog.
pineco - forretress (because pinecones turn to stell and grow big redspikes...don't they?)
It's not dramatic. That's like saying Pikachu's evolution into Raichu is dramatic because the shape of Raichu's tail changed and its an orange color. >_>
larvitar - pupitar - tyranitar (lavitar - something - tyranitar is fine, but where did pupitar come from? sucky-town?)
As the name suggests, Larvitar is the larva form, Pupitar is the pupa form, and Tyranitar is the final result (whatever that form is called). It's pretty similar to Caterpie's evolution line in a way.
combusken - blaziken (chicken to martial artist. o.0)
Not dramatic at all, and Combusken was part fighting type so... yeah. =/
I forgot about Clamperl. A clam does not turn into an eel. D:<