i read an article by david suzuki in which he compares agriculture to human culture. In it, he presents how horticulturlists determined back in the 50's that at a genetic level, there are astonishing differences between say, 2 flies, or 2 pumpkins, what have you. They then discovered that they were leaning the wrong direction, instead of trying to find and exploit one specific 'super' genome, they figured it best to assault the environment with diversity to get the best yield of crops. A smart farmer new this long before any scientest put a name to it, as with most things. When a crop is rooted into specific exact form genetically, weaknesses and susceptibality to disease are overwhelming common.
Human culture is not that different. After the collapse of the soviet union, amazing new technologies came out to the rest of the world, particularly hovercrafts and laser eye surgery. A walmart is a walmart is a walmart. We're spreading the herd thin. If a condition effects the physical, the same stressor under different context will effect the mental. Globalization simply doesn't work.