Then again, I have to remember the results of Wedekind's experiment in 1995 (Wedekind et al., 1995), where his team concluded that we tend to choose our partners which are genetically more unrelated to us, thus our offspring can be healthier and more handsome. So from biological/evolutionary perspective we can only engage people to get married with a partner from another country/nationality/race.
Of course these two examples mainly come from that part of society, which is not well educated, thus homophobic and racist. Traditional values which mainly are based on religion, can suppress our innate behaviour, thus nationalistic and "traditional" thinking is not supported from biological research, although this behaviour can be explained by "the selfish gene" (Dawkins, 2006).
Other role of this kind of research is just to educate people, get people interested in science, because biology can explain who we are and how do we function. For me this kind of basic research just simply satisfies my curiosity.
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