4. Volcano Explosions
In 2.5x108 years ago, Siberian Traps ( huge volcano explosions ) are supposed to cause massive extinction ( P-T boundary ), which is one possibility of our ending. In P-T boundary, 80% and more species became extinct. In THEIR world, it is often seen that THEY have stuck on earthquakes and volcano explosions. It is supposed THEIR demonstrative threats but it should be thought about another reason. THEY might be thought to make new volcano traps. It would take for tremendous time to make it, but ...