Observation on darker

I noticed that termite mouth pieces are a darker color than the rest of their bodies. I thought that maybe it’s darker because it had a more evil (evil as in harm to another) history to it. That or it’s tougher so it’s darker.

Then I thought maybe black and dark animals/ animal parts are tougher because they are evil. Like if you’re around evil it toughens you up with its harm. Like people being mean to each other is evil but it toughens some up to be able to handle more being mean to them.