People's minds have evolved to recognize aspects of other peoples' biology that makes them an appropriate or good mate.
This area of theory is called optimal outbreeding hypothesis.
Today's concept of fetish stems from two very different modes of analyses — one originally formulated by Marx, the economic or social; the other by Freud, the psychological or personal.
Marx's In Capital described fetish as a "mysterious thing that serves as the object of capitalist exchange".
One of her central arguments is that although race, class, and gender are all different and articulated categories of being, they always exist "in and through relation to each other," and therefore discussions of racial fetishism also always have to do with class and gender as well.
"not see racial fetishism as stemming from an overdetermined relation to the castration scene.
Reducing racial fetishism to the phallic drama runs the risk of flattening out the hierarchies of social difference, thereby relegating race and class to secondary status along a primarily sexual signifying chain".