For what reason is the ideal social unit a group of two? For every man desires a woman, and every woman a man… or, more broadly, every body generally desires a partner. Of course, there are exceptions, but one cannot doubt the “couple” is a prevailing trend. It is so pervasive that many feel it is the goal of life, necessary for”completion” – they seek their “other half” so that they may grow old together. Why so?

Certainly there are no shortage of biological possibilities for explanation (at least while assuming the more popular man-woman coupling). Biology equips us with a desire, so the story goes, to spread our genetic material. So, we desire a mate. Fair enough, seems sensible – most have felt biological effects that can reasonable be attributed to this assumed desire. But, why then does it stop at one partner? Perhaps it makes more sense in the short-term, human children are frail, and it does no good to spread your genetic material if you’ll not bother to ensure it survives. The couple endures to rear their young. But, could there not be one man and two women? Would it be much more difficult for the man to protect/provide for two children from different women than two children from a single woman (twins)? Why not diversify your portfolio of genetic successors? Which leads to the next wonder… why does the ideal biological union linger for a lifetime?

The answers may very well not lead us out of the biological woods just yet. Blame it on biologically-inspired jealousy. You’re not simply equipped with the desire to spread your genetic material, but to do so more successfully than your peers. It is easier for me to justify jealousy on behalf of a woman than a man. The woman is vulnerable during her pregnancy, she needs her partner’s undivided attention to ensure he provides optimally for her needs – thus ensuring a healthy child. If the man won’t commit – well, he just wont be spreading his genetic material. He commits, because he must. Of course, we now jealousy isn’t a one-sided ordeal. Many men are jealous. It could be that this jealousy is simple a restrained version of – kill your opposition. I suppose it is not too far-fetched.

However, I’m still not convinced this accounts for long term unions. It seems to me that these explanations of jealousy would mostly dissolve after the short-term child rearing. Based purely on biological motivations – the couple should separate and try numerous other genetic combinations.

And, well, we can’t pretend biology answers most of the aspects of this couple setup. What about the couples that don’t ever have (or want) children, and the same-sex partnerships, or the kids that talk about getting married long before they ever hit puberty? What can biology say of these? What advantage here does the two-person organization provide?

Financial stability would likely be better ensured by much larger groups, so too would entertainment value. Intimacy might suffer with groups that get too large, but not in smaller three or four person configurations. Are there social constraints? Sure – four people can’t get legally married – but marriage rates in many countries are slumping, and social constraints were not strong enough to suppress same-sex unions. I doubt they could overcome a strong desire for alternative social units.

What can we make of it? Simply some desire to emulate our parents, or the parents of pop-culture? Might society one day fill itself with groups of four or five partners – or will couples linger? And if they do, to what can we owe their success?

I’ve a few more thoughts on this subject… but they’ll have to wait. Until next time…