Why does nature seem to sense when something bad has happened in places for example in Bergen Belsen, when I visited,

Question: Why does nature seem to sense when something bad has happened in places for example in Bergen Belsen, when I visited, the birds didn't sing, nothing really grew and it was just generally like nature knew what had happened and had decided to leave the place alone, why is this?
- Keywords:
  animal,
  bad,
  leave,
  nature,
  sense
Asked by ladysovereignezza to David, Luna, Mark, Melanie, Probash on 23 Mar 2011 in Categories: General.
- Luna Munoz answered on 23 Mar 2011:
  
  I think it’s interesting that we selectively attend to things based on our mood. Research shows that people will miss certain parts to a scene because of the mood or the preconceptions that they have. I think that’s what you’ve experienced. A mood is a powerful thing!
- David Pyle answered on 23 Mar 2011:
  
  On the contrary, I suspect that our senses/perceptions can play tricks on us, filtering external information in ways which enhances our sensitivities to the outside world. Is this the same process that makes us feel frightened at night, in places which are otherwise familiar?

Question: Why does nature seem to sense when something bad has happened in places for example in Bergen Belsen, when I visited, the birds didn't sing, nothing really grew and it was just generally like nature knew what had happened and had decided to leave the place alone, why is this?