Polygamy

I once heard an old joke. Polygamy is having too many wives. Monogamy is the same. Polygamy can be defined as having multiple partners in a marriage. It can be found in three seperate forms, polyandry, where a woman has more than one husband at the same time, polygyny, where a man has multiple wives at the same time, and group marriage, where there are multiple husbands and wives.
Suprisingly to me, according to the Ethnographic Atlas Codebook, of 1231 societies studied, only 186 were monogomous, 453 practiced some polygyny, 588 had more frequent polygyny, and 4 were polyandrous.
These statistics were staggering to me, in my westernized point of view. I had always thought that polygamy was a rare and infrequent occurence, even in other cultures. I guess that shows what I know.