Curiosity contributor Diana Bocco examined the impact of marriage and monogamy on our well-being, and here's what she found.

Experts have long debated whether humans are meant to be monogamous. For decades, evolutionary psychologists have argued that monogamy goes against natural urges for reproductive success. The fact that sex doesn't always lead to reproduction in the modern world is secondary -- the innate urge is still there, especially in males. In fact, only approximately 5 percent of the world's mammals are monogamous [source: Harmon]. And recent genomic research indicates that many ancient populations favored polygyny -- meaning men had multiple female breeding partners. So at least genetically and biologically speaking, it seems maybe we weren't meant to have just one partner.

Does that mean we're happier when listening to our "gene call"? Not necessarily. A Gallup poll study on happiness found, among other things, that women are happier when they're in a relationship, rather than single and with an unstable sexual life. The happiest people were not only better off financially and more educated, but they were also involved in satisfying relationships that provided both sexual and intellectual fulfillment [source: Essig].

In their book, "Premarital Sex in America," sociologists Mark Regnerus and Jeremy Uecker claim that there's a connection between promiscuity and depression, just as there's a connection between happiness and monogamy. Many argue this is difficult to truly prove, as "happiness" is relative and there's really no experimental proof that the two things are connected [source: Fisher]. For example, it's possible that people who end up in happy, monogamous relationships were happy already on their own and simply carried that happiness into the relationship.

There are exceptions, of course. One is the case of the polyamorous, who engage in more than one committed relationship at the same time. Polyamorous people don't usually have casual sex or affairs -- instead, they're more likely to be married and have a long-term girlfriend or boyfriend at the same time. And yes, the partners are supposed to be aware of the arrangements and often have their own relationships as well. Can something like this actually work? Clinical psychologist Deborah Anapol, Ph.D. says polyamorous couples can be perfectly happy if each partner brings his or her own happiness to the relationship, rather than looking for happiness in the other person [source: Anapol].

The bottom line is that happiness is relative. There's no universal truth regarding what brings happiness and what takes it away. As with many other things in life, it might just be a question of following your instincts and choosing what works for you.