Perpetuated religious hysteria. I can't fathom a relatively primitive culture somehow being able to foresee something that modern science cannot. There have been end of time prophesies for, literally, thousands of years. It's sort of in our nature, I guess.
We're truly masters of our domain. While I think that there's some validity to the statement that the earth is capable of "cleansing" itself, e.g. population thinning viruses and diseases like HIV, modern science and technology has reached a point where the effects of such things can be mitigated to such a point where it has little effect on the growth of our species. The idea that the world will come to an end during our lifetime is almost a delusion of grandeur, IMO. Unless an asteroid smashes into the planet, or the sun sends a huge burst of radiation our way, we'll go on just fine- that is until our wasteful and damaging ways make the earth an inhospitable place to live. Enjoy the ride, friends.
lol thats what the mayans were talking about