Here's something completely crazy. If I remember right from back in Physics (good times), the greater the mass of something, the more it attracts things toward itself. Like gravity for instance. The Earth is heavy, and it's literally the Earth's heaviness that pulls us toward it. That's why gravity isn't as great on the moon, 'cause the moon's mass is smaller.
So what if there is something on (or under) this island that is so dense that it actually has enough mass to draw things toward it the same way that a planet does? If that were the case, it would probably mess up the Earth's rotation. So maybe Des really was saving the world?
Actually this doesn't really make sense at all, 'cause then the survivors would have probably noticed by now that they feel twice as heavy as they usually do and probably wouldn't be able to walk. Aw, wait, wouldn't be able to walk, how about that.