[Oddsville]

Well all of Oddworlds creatures have some type of 'soul'. Wheather it be Muds, to plantlife or even insects. Oddworld is a world full of souls and essence. Its like this, the more complex the lifeform is the more complex the soul is. If say.... a Mud dies then it can be reincarnated because it has a complex soul and was very intouch with nature, but a plant is not that complex and had an even bigger bond with nature which leaves its fate to be decided by prehaps a higher force?... Glukkons on the other hand are different. They cannot be reincarnated sience they did not share a natural bond with nature, and you get the rest.