[Ryzorian]

It might also be that idea of taboo, that some things are forbidden fruit as it were. Afterall, whats the first thing a child does when you tell them they can't have the candy sitting in the jar?

Cultures are the same way, it's how you get crazies like the KKK complaining about "keeping the race pure". Course, the moment something becomes forbidden, it attracts. So that prolly has something to do with it as well.

While culturally speaking some of these are a result of the taboo factor, I still think much of it is natures atempt to create stronger bloodlines through hibreds.

The irony is that those who advocate keeping the so called "races" Pure are in fact advocateing keeping thier own race weak. I'm from Iowa, where we have alot of corn...all of it super hibred versions. Heck, the orginal "purebred" line of corn you would hardly recognize as corn. It certainly isn't going to produce 200 bushles an acre or be insect resistant.