Actually, according Atechnogenesis Cybertron did undergo an evolutionary process in becoming a machine world. Granted that Atechnogenesis was retconned out of canon and replaced with Primus Special Creation. So okay, Cybertron was transformed into a machine world!

Quote Originally Posted by kup
There is something else that BM stuffed up as it also implied linear evolution of the origanic world before Cybertron and Primus' reshaping of hat world.
I don't recall Beast Machines ever stating evolution being the process by which Cybertron became a mechanical world. Simply that Cybertron was once organic, but then became mechanical. Precisely how it became mechanical was left open to interpretation.