[Old post - 2009]
Human women(!!!! hehe! Human females? I think I mean) are continuously breeding.
Chimps have a baby once in 5 years in the wild, same with the other apes... and people??? They would have a child every damn year. spreading across the whole earth like viruses to quote matrix.
women are particularly vulnerable, I mean every other species female is quite capable of taking care of the young all by herself or with the help of other females. Not so in the humans.
Both chimps and bonobos are polygamous. Offspring are spaced at 3-5 years difference, female is capable of bringing up the itself or with the help of other females. Not so in humans cause the offspring are spaced only years apart if not regulated! why was this?
I think this was because..
Humans almost reached extinction some 1000s of years ago(According to one Nat Geo feature), only a few thousand individuals were left, I think this period heavily favored the fast reproducing genes in humans, has mostly shaped reproductive cycle and also the society.
female - will reproduce as many as possible. the society will take care to see that these survive. In this process, It didnt matter if the female was strong enough to take care of the young only the frequency mattered.
This also lead to dependency on the male, the females who were dependent on the male were able to produce more surviving offspring than those that were independent. Also as a corollary those males that did support and provide for their offspring had more success with their genes than the lazy (? :P) ones. Those groups which adopted this mode, to support and feed the female and young as community must have survived. I think this is probably what tipped off the almost extinct species to bounce back...but as a down side this produced high fertility( which wasn't a problem until medical science made so much progress that everyone survives) and also prevented weeding out of complicated pregnancy genes, even if the mother died her kids survived and carried on the bad genes.
Polygamy v/s Monogamy, Polyandry
Monogamy is suited for a place where there is plenty but it needs hard work to get it. like Europe. They had more higher quality food than us(tropical people), but it required hunting, lot of effort. one male couldn't probably support more than one female . also the females need to more independent and strong in such environment, following the hunters, as they followed deer/bison herd migrations with seasons, for long distances, Endure hard weather...Thats why Scandinavian British women as almost as tall and strong as the men. number of offspring is lesser. few but better quality offspring. The risk of death of well provided offspring and mother is less due to disease. Independent families, easier for each family to feed themselves.
Polygamy is suited for a very fertile and abundant place, where it is easy to provide for food but has a high death toll by diseases. The probability of a strong kid dying is same as a weak kid, It makes more sense to have smaller but many more kids, so loss is minimized when any one dies. Polygamy is the most efficient way to grow. Thats why its used in chicken/sheep farms. Popular in China, India - middle east and Africa. Value for women and children is less in such a situation. The focus is on number and than quality. Each man can have 10 wives and 10 children each.. probably 7 out of the children died in their childhood due to diseases. So women were almost always breeding, They are weaker, less independent, agriculture and therefore more settled lifestyles. Large joint families.
In some places like middle east and central Asia even tho climate was bad,land not fertile - there is polygamy. I think because of higher competition men clashed and died a lot more than women? I think middle east has polygamy because of frequent wars, India china and Africa because they can afford it.
Polyandry - results in female taking care of the offspring - unless all the husbands are related. Its seen in Tibet and north east... its more suitable for a population that does not want to grow and keep a stable population because resources/space are scarce and there is no scope for growth.
The main aim of marriage or partnership is to rise offspring, humans love cause humans who loved raised more live offspring than those who didnt. Marriage has existed for millenia cause married couples rise more children than unmarried. Even in cultures which support polygamy, marriage or formalization of the partnership exists indicating it is necessary for survival. We are animals after all. community care of children will work only if the community consists of genetically similar - relatives/ sisters etc.. cause our genes are selfish, we are still animal enough to care about these things. The society or culture or our group psyche does not care about individual happiness, it only cares about the continuation of the species successfully. Atleast until now.