User blog comment:FinalFlash18/Selection process/@comment-48285-20140324154155

Welcome back. As for the topic: The way I understand it is that the humans are gathered together and then their placed inside of those cocoons somehow. That's when they're transformed into chimera ants. Only the 1% of them are strong enough to withstand the process and are reborn. Those who aren't strong enough, die. That's the basic explanation of it, I believe.

As for your second thing, I don't know. I don't really have any episodes in mind.