It is often taken for granted that we as a species have made it this far. From prehistory up to the present, the list of things that could have gone wrong is virtually endless. From natural disasters, to global pandemics, to frustratingly human problems that brought us far too close to the edge, it is certainly not just strategy and survival instinct that have brought humanity to the 21st century; a good deal of luck has been involved as well.
Read on to learn about the catastrophic close calls that could have changed, or ended, life as we know it.