Ok DA,

If religion was not repressing knowledge how is it that during much of European history they preferred to use leeches, cut holes in people's heads to "release demons" instead of learning from the Orient who they traded with for centuries? Europeans have always felt that anyone who was not white or Catholic was inferior and their knowledge was useless.

I will provide you with more links at a later date re: ethnobotanists and what they are learning and I am sure that they will meet your standards.