But is this any different from human women being attracted to a certain TYPE of male? And it would also need to determine first wether the human tendency toward monogamy is cultural or gentic.
It is my belief (from personal observation) that human beings are not
inherently monogamous. Not by a long stretch.
I am by no means an expert on the animal kingdom, but from what I've seen, all mamilian species that live in social groups are not at all monogamous! Most especialy primates, Cats (both great and small) Canines (Wolves and Dogs) and herd animals (horses, cattle etc)
These groups consist of an Alpha male who gets his pick of the females. Occasionally that alpha might
allow one of the other males to mate with a female, but only occasionally. Sickly and/or weak males are not allowed to mate period
. The females will not allow it. This is the animals way of weeding out genetic abnormalities to keep the species strong.
Monogamy in humans is cultural. It is deeply rooted in religion in most cultures. This is humanity's way of enforcing a form of "fairness" on people so that every male has a chance of mating. Simply the fact that there are far more females in our society than there are males should be a clue to our genetic heritage of polygamy.
There is a great deal of evidence in front of us in the form of High school drama. The "Alpha" males of high school are invariably the Jocks and popular guys who get their pick of the chicks. With only a (very) few exceptions, most of the girls in school dream about being the quarterback's girl. A good-looking, athletic guy, regardless of his personality will be the center of attention with multiple women vying for his affection. Also men with strong/forceful personalities are seen by many women as Alphas. This "strength" is quite important to women instinctually as in nature females will seek out males who have the strength to protect the "family" from predators. At the most basic level, this is why many abused and battered women refuse to leave their abusive husbands. (and a low self-esteem doesn't help either)
Also don't streatch too much how long Ietta has to wait between Rognars. She is not much more than 300 years old and should be on only her second Rognar, and maybe only her first, when we meet her in 2990. She does have Sopp as her "fall back master", and she has never been in a postion where she has lost Rognar but been out of the protection of Amatarasu. And in Fatima terms it doesn't take long to regnerate a Rognar, maybe 25 years. At which point, even though he has a boys body the mind is mature enough for the daughter chip to work and he has fully regained his powers of mind and can start being her master again. In the meantime, she seems to function, like Majer, as the child Rognars foster mother. Thus the amount of time she is truely without Rognar is measured in maybe months.
Rognar is lucky to have her, because otherwise his life would be really lonely due to his form of mental imortality. Their closeness therefor is more than just husband and wife.