Forum:Was the G.M.W. the ONLY cause for humans to die???

http://images4.wikia.nocookie.net/__cb20091227230730/adventuretimewithfinnandjake/images/archive/b/bc/20100401212842!Wiki.png

OK, most people are pretty sure the Great Mushroom War (G.M.W.) was the cause of most of the human decline in numbers. But did people ever think that there could be TWO causes? This is just a therory, but I couldn't stop thinking about it. In the opening sequence, a scarred and BITTEN arm is on a tree, but it's hard to see. So, skipping to the point. A few years after the apocalypse, everything was mutated and unstable. Some humans had survived though. But then came the rainicorns, eating most of the humans. The last clan of humans split, separating into two. One group went underground, thus creating (over years of radiation) the Hyoomens. The next group stayed above, surviving how they could. What happened to most is unknown, but Finn was a child from this group, for some reason abandoned. My therory could be completely wrong, but it's a pretty good way of pulling things together in my mind.