The amygdala is one of those brain structures that a lot of people know a little bit about, and there's a definite tendency to conflate the amygdala and the fear response itself - as if the amygdala, and the amygdala alone, 'causes' fear.
The more that I looked at DNA, the more I realized it was nature and nurture. It's how genes and your environment work together to produce the person you are.
If studying the periodic table taught me nothing else, it's that the credulity of human beings for periodic table panaceas is pretty much boundless.
Our evolution could have gone in different directions a lot of times. We could have gone extinct at some points. We might not have gotten our big brains, or Neanderthals might have made it while we did not.