there are things called human evolution. Humans will evolve to adapt in conditions. For eg, if suddenly there are no sun, the human senses will evolve to adapt for this condition such as development of better night vision or bigger eye or relying on better hearing and better IR detection from skin like reptiles and so on.

This is what evolution is all about and why we human came to what we are not out of RANDOMNESS but out of evolution and survival of the fittest.