Know the difference between polygamy and polyamory. Polygamy isn't that uncommon but is often used to serve patriarchal hierarchies. Polyamory is much closer to "do whatever" (though that's not strictly true).
I'm trans and let me tell you so many of us are polyamorous. In my personal experience it has to do with spending so much time fighting against society to claim our identity that we end up questioning a lot of social norms. I think that more people than we realize could live very happily being poly, and if we had better poly representation more people would know how to approach it in a healthy way. But it doesn't serve the hierarchies we live under to let people love freely in that way, so it gets othered in media and by governments.
Also the "groups" you're talking about teaming up in are typically called polycules. There are a lot of forms they can take it is an umbrella term.
I think that as people are made more aware of the harm caused by some aspects of society we'll be better at questioning things like monogamy as a whole. It isn't an overnight thing. Also, often even in the poly community it is considered an unstable way to raise children (I don't agree with this but it is a common enough sentiment). I don't think polyamory will overtake monogamy certainly not any time in my life but I hope it becomes more common.
I think polyamory is an immutable part of someone's sexual orientation as much as the gender preference spectrum (homo/heterosexual) and the intensity/situationalness (ace/gray-ace/demi). I think some people just naturally see sex and intimate relationships as something they can do openly with multiple people and some people just don't. I think it will become more acceptable for the people who see sex that way to find each other and express their love that way, the same as with all the other sexual relationships between consenting adults are becoming more acceptable. But the same way it would be silly to say we'll all be homosexual eventually I don't think we'll all be poly someday either.
It appears to be pretty stable through history and prehistory around the world, so it's probably biological. Occasionally cultures allow limited exceptions but they're usually one-sided. This lines up with my personal experience, which is that some people are capable of being poly, but most people just aren't.
I think monogamy will continue to be the default MO of relationships although divorce will become more common as life expectancy keeps increasing. I also think acceptance of other relationship models will increase but I doubt they'll become prominent among lower classes, having one partner already is a lot of work and people with little in terms of money and perspective are unlikely to be able to afford that full attention for another partner. (yes cheating is a thing, it usually also involves either a reduction in relationship activity with the cheated on or a relationship light with the affair partner)
Anecdotally speaking, probably not. I haven't seen many poly relationships really last, nor have many of my friends (all queer).
I do see the rise of grandparents caring for children as a thing though, as wages continue to stagnate and both parents are forced to work. Intergenerational housing too. Multiple friends buying houses nearby and caring for kids if one parent is fiscally fortunate enough to be stay at home. That sort of thing.
The main problem with polyamory is the jealousy. I have experienced jealousy maybe three to five times in life, because I was an only child and I have a very laid back temperament. I think if we start prioritizing quality of life more as a society, parents will be free to raise their children well with less insecurities, and maybe that would result in more people gravitating towards polyamory. But it's really not for everyone. Poly is hard work.
Monogamy assumes marriage is a natural thing people do. People are getting married later or not at all in increasing numbers.
I don't even think monogamous marriage is the main relationship style if you consider people that have affairs, divorced people, serial monogamist, etc., not part of monogamy. It's over represented in media but that norm has changed a bunch in recent years as well.
There are also tons of relationships that aren't marriage. FWB, poly, one night stands, etc.
I think the question could use a rework to clarify if you mean legally, socially, etc., as well.
Here in the Pacific Northwest, the vast majority of people under 50 seem to be in polyamorous relationships. I'm fairly new to poly, but I've done a lot of reading and therapy, and it's working out pretty well for me.
I do tend to be people's anchor partner, so I've admittedly never experienced the pain that comes from being a secondary when you wish you were a primary. My anchor partner tends more towards relationship anarchy and doesn't like hierarchical relationships, but i made it clear that my expectation is to be the priority in her life. We've made it work, although it takes a lot of communication.
Some animals mate for life or mate exclusively, others don't. It's not "the main form of earth," it's the norm by which humans establish long-term romantic and sexual relationships and raise their young.
I don't think society will forget that any time soon, but it's hard to predict the future. Culture does change over time.
We have already seen a huge change as it's much more acceptable to be in more relationships and getting a divorce.
If people start to live a lot longer you will see people changing relationships more.
With AI there is already worry about people getting into romantic relationships with AI partners.
If we ever achieve long-term life extension, I could see monogamy being tossed. Being with a single partner for life can serve well if it's the ideal of both parties in the relationship. But extend that lifespan to multiple times the current one, and I can see it getting pretty iffy.
In the ethical nonmonogamy (ENM) circles, the form of polygamy is usually frowned as it is a form of power over others. However polyamory and other forms of non monogamy are much practiced and common.
All forms of relationships will fluctuate as legal options throughout time. Polygamy is no different. Polygamy used to be common in certain parts of the developed world and is still common in places like the Middle East. Heterosexual monogamy is just the thing that it happens won't fluctuate, this is as it's like an axis mundi of relationships. That said, everything you describe is inevitable as a phase.
That said, I don't consider a relationship invalid or "less valid" no matter how many people are involved, their genders, their race, their creed, their medical history, how close they are, etc.
I think you are talking about marriage and family, more than just sex, right? Because sex-wise, you can do what you want already.
Polygamy no. I don't think that's what most people want, the sister wives thing. That's a system used when men are scarce and you are trying to increase the population quickly, neither of those conditions exist now, and polygamist systems are often dead patriarchal and nasty.
Polyamory? The make your own family, whatever configuration, more than 2 people? I think we are closer to that, yes. In a time when you are trying to decrease birth rates, yes families with more than just a couple might become popular. More parents to love and care for each child would be handy.
Polyandry, two or more husbands? That would work in a world where there were more men than women - but most of those places in the world right now are not places where a woman would have the freedom to do that.
Monogamy has never been the main thing. However, with the equalizing of sexes in marriage according to the law, I don't see how anything but monogamy can be legally until a lot of work is put into defining how three equal people can be married.
A form of polygamy is available to the upper class; it is called having a mistress. However, the mistress has no marriage rights; any rights would come from being the parent of a joint child.
@Violett_Queen I don't think it's already the case and we already generally do just do whatever we want, but are afraid to admit it to ourselves.
Also, are you talking about *gamy or *amory?
There's distinction.
Polygamy is about just sex pretty much. Polyamory is about romantic relationships.
If the former, then, a lot of married people have sex outside marriage. It's debatable how honest this is, most of it just cheating - but that already counts as polygamy.
If the latter... Unfortunately, we're ways off universally recognizing this type of relationship. For shame.
There's also the factor of polyamorous relationships being harder to maintain, requiring a lot more work to do properly. Despite what conservatives might say, this type of relationship demands MORE responsibility from all involved, not less. So, it's not everyone's cup of tea, and probably monoamory will be the default in most of the cases. But if you are willing and able pull it off, there's nothing quite like it.
I see a future where you'll need a contract to have a child and it will include support for 21 years between both DNA donors. Most people will lack the financial availability and would not qualify for parenthood. Illegal pregnancies would result in 21 years minimal prison sentence for both DNA donors.
With that, two person contracts will replace the religious concept of marriage. It will require an equal support for both partners financially. The contract would allow separation for domestic violence or failure to produce a human child. No Divorce would be authorized under any other circumstances. No new contracts would be authorized for a new partner if a DNA donor child is under the age of 21.
So yes, if you enter into a contract to produce a child, your stuck with that choice for 21 years.