In this Life's Extremes, we look at why some people prefer long-term relationships and are considered monogamous, while others are more promiscuous, some choosing polygamy as their lifestyle. read more
But if you mean "polygamy" as a marriage-version of "polyamory", where people can have legal relationships (such as in current monogamy) with multiple people and share all the same rights and responsibilities as monogamous couples currently do, I see no reason why that is better or worse than monogamy. read more