Three is no longer a crowd as the rise of open relationships threatens to make single-partner relationships obsolete.

The concept of being with one person for life puts a terrible taste in many mouths …and that may be the taste of the same person’s ejaculate, day after monogamous day. But thanks to a recent shift in attitudes toward open relationships, it’s looking like monogamy’s long reign might be coming to an end.

There is, after all, the biological argument that humans did not evolve to be monogamous, something author Christopher Ryan explores in his now stupidly famous book, “Sex at Dawn.”

“No group-living nonhuman primate is monogamous, and adultery has been documented in every human culture studied—including those in which fornicators are routinely stoned to death,” says Ryan. “In light of all of this bloody retribution, it's hard to see how monogamy comes ‘naturally’ to our species. Why would so many risk their reputations, families, careers— even presidential legacies—for something that runs against human nature?”

The answer, he claims, is that we’re just following our natural instinct toward slutdom. It’s a notion that, among other things, has contributed to the tide turning toward a world of multiple partners.

All of Ryan’s biological idea stuff notwithstanding, perhaps what’s contributed more to our perception that open relationships are kicking the shit out of monogamy is the media’s portrayal of an alternative lifestyle. TV shows like “Sister Wives” and “Polyamory: Married & Dating” are giving people a glimpse into the complicated sex lives of multi-partnered couples, and they’re liking what they see. We’re not doctors or anything, but this probably normalizes the practice to a point where couples feel comfortable discussing how they can augment their relationship to ensure both their needs are met.

“The interest and the visibility around open relationships has just skyrocketed,” said sexpert Tristan Taormino to the New York Post, who wrote a book on the subject called “Opening Up: A Guide to Creating and Sustaining Open Relationships.” "We’re having these discussions in really mainstream media that just weren’t even possible two years ago.”

Taormino also points out that, in the last year, her book has sold twice as many copies since its release in 2008, a testament to the sharp rise of interest in the topic.

But who exactly is interested? It’s not who you’d think. While a significant portion of open relationships are negotiated by horny men, it’s often women who are the instigators of alternative lifestyles. A study by sex researchers at the University of Wisconsin has shown that the group of people most likely to want an open relationship is women who have become bored romantically after several years of monogamy.

However, despite the recent surge of interest in open relationships, monogamy is still much, much more popular. A recent survey by YouGov and the Huffington Post found that a whopping 72 percent of respondents would never even consider an open relationship, while only 14 percent of survey respondents admitted to trying it or said that they’d think about it.

So, to answer the titular question: no. Monogamy is alive and kicking in all its prim, vanilla glory, even if alternative relationships appear to be the sleeker, sexier option. Because even while monogamy may not be encoded into our DNA, the social construct of the soulmate is embedded in our culture deeper than the dangly cherry ring in a stripper’s belly button.