Pokémon X and Pokémon Y

Tree looking thing > Tree
Fish with whiskers > dragon with whiskers
metal coin > giant metal bell
a cicada > a bee AND it's living hollow husk
a living pokeball > an upsidedown living pokeball
ant > dragonfly > dragon

point being, it doesn't always make sense. Sure it might not be an evo of sudowoodo, but it just fits the character artworks.

Gyarados: "Gyarados is partially based on a legend about how carp that leapt over the Dragon Gate would become dragons."
Bronzor + Bronzong: "Bronzong and the fact that it evolves from Bronzor also seems to be based on an old Japanese myth present in the book Kwaidan: Stories and Studies of Strange Things by Lafcadio Hearn. The priests of Mugenyama wanted to forge a bell for their temple, so they asked the local women to donate their bronze mirrors for this purpose."
Nincada is a larval cicada, Ninjask is an adult one. Shedinja is the exoskeleton shed when it becomes an adult.
Voltorb and Electrode aren't even relevant.
the Trapinch line is based on an Antlion: http://bulbanews.bulbagarden.net/wiki/On...and_Flygon

I fail to see your point, as all those pokemon have genuine origins that explain the changes they go through when they evolve.

So no, it still doesn't work. "tree looking thing" becoming an actual tree isn't enough of a basis to explain the evolution.