Immobile squares of flesh, made to retain their intelligence as punishment for their ancestors' resistance against the Qu invasion.
And I Must Scream: The ancestors of the Colonials put up particularly stiff resistance against the Qu, and were given an extremely cruel punishment as a result, being transformed into limbless, boneless slabs of flesh to act as living filtration systems for the waste of Qu civilization, reproducing both sexually and asexually and spreading like mats of cancer cells. The most sadistic part of the punishment was that the Colonials' eyes and minds were left intact, leaving them perfectly able to understand what was happening to them but unable to do anything about it. Unlike the Mantelopes, they at least managed to adapt and re-develop into prosperity after the Qu left.
Body Horror: The premier example in the whole book, and that’s saying something. They have no limbs, bones or anything other than eyes or brains. The Colonials are basically living mats of skin, made to live miserable lives by the Qu.
Mercy Kill: Many of them hoped for a quick extinction after the Qu left. Given the inherent misery of their lives, it's hard to blame them.
Sins of Our Fathers: For a given measure of "sins". The reason why they're forced to live cruel fates and filter waste everyday is because their ancestors resisted against the Qu, driving them back two consecutive times before being overrun.