The "Yuck" mechanism. What is it that makes one person (me, in this particular instance) detest the very thought of green beans, while another person - of very similar genetic makeup (my sister) - absolutely loves them? What is it that makes me completely sick to my stomach, when I see the maple syrup (that we left in the pantry for WAY too long) over-run by fungus that I would be fascinated to study about in a book? What is the "yuck" mechanism? Note: I know the evolutionary advantage of such a mechanism, so I know the "why", it's the "what" and the "how" that are beyond my knowledge. Any/all comments on the subject are definitely appreciated.