kd4

well lets start with what I think should be cleared up. Most of you are talking about polygyny which is a type of polygamy, polyandry is the other. Polygyny is the marriage of one man and two or more women. Polyandry is the other. Those are strict with just one of the two sexes. Polygamy is with more than one of both sexes in the relationship.
Now to Scott. If you look at other cultures that accept polygamy in either of its forms, there will be the problem of jealousy. For simplicity lets say polygyny. That is sometimes taken care of by a "chief" wife who dictates who gets to sleep with the husband and when. She basically mediates and tries to keep things fair. There is also possiblity of a "schedule" for each husband to spend with one of his wives so that none of the other wives will intrude.

People also state that polygamy is selfish. You're right it is selfish. In some case studies of cultures that do practice polygamy its important because it keeps property/wealth inside the family. Think about it. You have 3 sons, who marry 3 different women, then you die you split your land into 3 smaller parts with 3 separate owners. Then all 3 of them have 3 sons who received part of their father's share of his father's land. Thus dividing the land into even smaller pieces. Instead would it not be smarter to keep the land as one large piece instead of many small pieces? That is why in some societies women have multiple husbands.

This will be the last part, sorry for the long post. Polygamy in the form of more than one of each sex, IE 2 men 2 females, they share responsibilities. One woman can go and pursue a career while the other stays home to take care of children. This is a mutually beneficial existence. Obviously if both women wish to get jobs then a man can stay home with little to no ill effect at all on the children. Someone can always be with them and take care of them.

On a side note, I do not support polygamy in any form