Seems to me we have different levels of fear... some are probably genetic; the howling of wolves causes a lot of people's spines to tingle even if they have never seen a wolf or been near one... somewhere in our ancient genetic programming, that sound means "danger, you'll be eaten."
Most things are more learned, I'm sure. I always liked the "False Evidence Appearing Real" saying.
Yes, I agree, we have instictive alarms to danger, the same as animals. An animal that has never seen a man will still run from it.
I also like that quote. It is so true!