I want to see this study done with four islands, one with chimpanzees, one with bonobos, one with meerkats and the last one with wolves or dogs, ideally a breed of dog with a gentle temperament like labradors.
The breakdown of rat society seems to be because, well rats don't have a society, they're happy to share space with each other most of the time but to breed they need privacy, they need to be able to clearly smell and thus identify their young as their own, they won't raise their young in groups like humans will because their brains just aren't wired that way.
This is why it would be interesting to see the same study done with meerkats or dogs, they do have a pack mentality, and though chimps will probably just kill each other it would be interesting to see if any "beautiful ones" develop amongst them and what they might get up to. Finally bonobos might be the most interesting of all given how highly amicable they are to each other, their population might just keep expanding as long as they're given food until the whole island is covered in them, at which point I think it would be kinder to nerve gas the lot of them at once rather than cut off their food supply because I think we know what will happen next.
Then again we can't just assume, that's not really science is it?