Can the Rise of Singles and the Urge-to-Merge Coexist?

Can there be too many single people?

Posted Nov 18, 2011

During the discussion period of just about every talk I have ever given about singles, one particular kind of question is asked. I think of it as the evolution question, or the "whither the human species" question.

Evolutionary theory is not my strong suit. So I was especially heartened that in response to my very first publication about singles, "Singles in society and in science," two evolutionary psychologists wrote an article titled "The evolution of coupling." I'll highlight some of Elizabeth Pillsworth's and Martie Haselton's key arguments later in this post.

First, I'll relate several variations of that predictable question, and offer some of my own commonsense responses.

I.                My Thoughts on These Questions

#1 Question I am Asked at the End of My Talks

How can the human species continue if too many people stay single?

When people ask this question, they seem to be thinking that single people do not have children. Of course—as they realize in an instant—people do not need to be married, or even coupled, in order to have children.

#2. Question

Even apart from reproduction, who is going to tend to the next generation, and contribute in other ways to the continuation of the species, if too many people stay single?

Many years ago, a colleague and I were talking about a brain surgeon. My colleague said something like: "Too bad he became a brain surgeon. He can only perform so many brain surgeries in his lifetime. Think of how many lives he could have saved, long after his own life ended, if only he dedicated himself to brain science. As a scientist, he could have made discoveries that other brain surgeons could use for generations to come."

Scientists who never parent but who come up with advances in reproductive health may contribute more to future generations than people who have a few kids of their own. People who dedicate their lives to teaching may reach many more students than do people whose teaching competes with their own children for their attention. Singles who do not have their own children, but who nurture nieces and nephews and kids of their friends and neighbors, are contributing in ways that are often overlooked but shouldn't be.

#2a.  The Question I am Never Asked

Wouldn't we be better off if there were not so much pressure to be coupled and to have kids?

Sad to say, some people are terrible parents. Minus the chokehold, maybe some people would have realized that they should not have had kids.

#3. Question

Doesn't evolution tell us that we all have an urge to merge? Can there really be adults for whom coupling just isn't all that important?

My guess is that the urge fits a bell curve, like so many other human qualities do. Most people will have that urge, but others will not—or will to lesser degrees.

II.              Quotes from Pillsworth & Haselton, "The Evolution of Coupling"

A.    An Evolutionary Take-Down of Modern-Day Matrimania and Intensive Coupling

" is certainly true that sex and mating are central to the evolution of species like humans, but we see nothing in evolutionary theory leading to the prediction that the reproductive pairbond is the only relationship of importance, or even the primary one."

" most cultures around the globe, your spouse is not your best friend, or even your primary social partner."

"There is, therefore, nothing from an evolutionary perspective that would suggest that all relationship roles can be collapsed into a single partner. Each type of relationship serves its own unique set of purposes, guided by specialized adaptations."

B.     An Evolutionary Perspective on the Supposed Superiority of Coupled People

"...the fact that humans have adaptations for coupling does not imply the moral superiority of coupled individuals."

"The evolutionary perspective on coupling also does not suggest that coupling will result in a healthier or more satisfying life for any particular individual."

"In the modern world, coupling also does not guarantee an on-average fitness benefit to couple members or their children."

C.    An Evolutionary Perspective on the Myth that What All Singles Want, More than Anything Else, Is to Become Unsingle

"Nor does [our argument] mean that the desire to form a couple will always trump other evolved motivations, such as the desire to pursue alternative reproductive strategies, care for kin, or strive for status."

"The information value of mateship status may be greatly distorted in modern society [where] there are many exogenous reasons why a person might remain single. Attractive, intelligent, kind, and otherwise desirable individuals may be single because they are pursuing other challenges, such, or other forms of personal fulfillment."

"The sheer number of alternative courses of action available to modern humans, the advent of reliable contraception, and social norms promoting the pursuit of a career are likely causes of the rising tide of singles and the decision by many to remain single their entire lives."


DePaulo, B. M., & Morris, W. L. (2005). Singles in society and in science. Psychological Inquiry, 16, 57-83.

Pillsworth, E. G., & Haselton, M. G. (2005). The evolution of coupling. Psychological Inquiry, 16, 98-104.