Indeed, human and for that matter, all of animal behaviour is BASED ON THE SINGLE POINT AGENDA: ” how efficiently can you replicate yourself”
Any act of sexuality, its abuse, social arrogance, or perversion in any society can be explained on the basis of this. For example, among mountain Gorillas and many other animals the alpha male (the dominant male of the herd) is notorious to kill male kids of the species, in an attempt to avoid future sexual rivalry.
Most males among animals are literal RAPISTS. The arrogance, chauvinism and the sexual anarchy of these males result from hormonal overdrives. And this is the genes’ way of sowing its replicas in maximum wombs around..! Sigmund Freud’s theories of sexual basis of family bondage finds justification in these behavioural patterns.
About sexual attraction : Darwin explained that the bright colours of PEA COCK feather was a signature of GOOD HEALTH..! Similar explanations hold true in Caucasian men preferring BLONDE haired females.(Ramachandran V.S, University of California) Skin and Hair are excellent indicators of body health.
Symmetry of the two halves of the face is also a strong indicator of beauty (and indirectly health). The ratio of distances between the forehead, bridge of nose, lips and chin are good indicators of facial beauty too. Faces that are closer to the perfectly “proportional” ideal face look attractive to us, though the in human males, other qualities are more often looked for.
Even though in animals POLYGAMY and sexual anarchy is the rule, in humans its not always same. Human females spend a lot of their time and energy to rear their young. So they always ensure that the male partner is healthy to produce healthy young ones,trustworthy to help her bring up a family and hard working to feed her young ones.
There is also a similar explanation for the concept of marriage. When humans started living around cultivated lands, cooperation was the foremost thing needed.And thru “marriage” a male declares that the lady “belongs” to him and that any intrusion into their privacy will be seen as a breach of this unwritten contract among male members of the community. To ensure his dominance over the female partner, very often he chooses a lady from a “socio-economically lower” family as wife. Through this “unwritten but implied” contract the male establishes his niche in the society he lives. This same “selection” is the reason why mothers are closer to male children and fathers to female children
The individual’s struggle for achieving higher positions in life is a reflection of his genes’ struggle for a social acceptance. This struggle in animals lower in the hierarchy shows out in the form of cock-fighting, nuptial dance(mating dance in insects), or even nest building among some birds. Those males who can impress the females and prove he is a “family man”, wins. When it comes to humans, this show off of “social status” range from mere athletic excellence to winning a Nobel Prize.
Remember: The centers in the brain that give men a sense of self gratification and pride after having achieved something (and often boasting about it), is very closely linked to sexual pleasure centers..!!