Will buildings evolve

[Hooba]

Will buildings evolve into new (larger) ones, when a city has grown larger. Or will most of them stay the same during the game?

Greetz
Hooba

[Frujin]

They will evolve.

[Pikeman]

Will we also get big towns growing beyond their walls, maybe ending up with a second curtain wall surrounding the outskirts?

[G_R]

My question is how will those buildings evolve-with special upgrades or by the size of your country or something else ?