Non Sequitur - Does Not Correlate.
Labeling something as "Fairer" than something else does not cause it to be more attractive, nor does it cause the "Fairer" sex to be more successful in getting partners.
Consider this: In a binomial system of "one woman plus one man", men and women actually have an equal chance of having a romantic partner. Think about it ... in order for one woman to "get a partner", one man has to "get a partner" too! Thus, there is no real inequality, only the perception of inequality in the minds of men who can't get a date - it is equally as easy for any one man to hook up as it is for any one woman.
Of course, personal attractiveness counts, but only on an individual basis.
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The mere fact that science may not yet adequately explain an object, event, or experience does not mean the immediate explanation should automatically default to a conspiratorial, extraterrestrial, paranormal, or supernatural cause.