Haha, that is thought to be one of the reasonings for these genes that they arised for natrual selection.
I also discovered something really interesting that I might try to start an independent research project of sorts over the summer (partly because I have found no research into this). I discovered that ortho-vanillin is actually a smelling version of PTC. It started when I found a bottle in the lab, smelled it, and found it to smell lovely. Then someone else smelled it and said it was gross. I tested it on my ochem lab students. Perfect 50/50 split. Some though it smelled lovely, others thought it was nasty. Also note that para-vanillin is the stuff in vanilla extract so it is slightly different.