Will it be man or natural phenomenon?

Its definitely man who is gonna end life on earth cause man with his research has invented as well as invited dark hidden diseases like Aids, Cancer and lots more and who knows how many hidden diseases are to be revealed as science touches new heights, but with this I don't mean to be treated to live a better by chance I get infected with any of those dreadful infection like cancer or something, but all this is leading to end of mankind, all those earthquakes and natural disasters happening I believe is happening, to maintain a balance in nature I don't under stand how is earth floating in space while even if we could float on water any addition of mass would sink us, but I really don't get how is earth still floating without going down what I that which is keeping it afloat, these things are quiet complicated and i hate physics that could be the reason I haven't understood that but coming back to your question it is mankind who is gonna end life life first on earth. if and only if would be a little kind hearted toward the beauty of nature and stop doing damage to its beauty.?

I think it will be man that will end life on earth. With all of the wars and chemicals and waste that we already have, in part man's actions are already ending life.