Women are attracted to "outsiders" it's genetic and aided survival. Women were made this way to ensure genetic diversity. A man will CERTAINLY go for an outsider...but it's important for women to be attracted because women needed to get "seed" from outside the community group to ensure genetic diversity.

BEFORE you go off half cocked about "diversity" this is NOT the same as what YOU are thinking. This is WITHIN THE SAME SPECIES diversity. This isn't saying we should mix "them" with us. It's not mixing a cat and a dog. This is to prevent too many recessive "bad" gene combinations through too selective, too narrow breeding, not enough partners from living in an extended family. Trading women also brought down the violence between "tribes" as the women were related.

"Diversity" between the races is NOT beneficial.