Basic principles of biology rather than women’s newfound economic independence can explain why fewer of them are getting married and having children, and why the trend may only be temporary, says a Queen’s researcher.

“Only in recent times have women acquired significant control over their own fertility, and many are preferring not to be saddled with the burden of raising children,” says Lonnie Aarssen, a Biology professor who specializes in reproductive ecology. The question is whether this is just a result of economic factors and socio-cultural conditioning, as most analysts claim, or whether the choices that women are making about parenthood are influenced by genetic inheritance from maternal ancestors that were dominated by paternal ancestors.”



In a paper published in the current issue of Oikos – an international journal of ecology – Dr. Aarssen suggests that because of inherited inclinations, many women when empowered by financial independence are driven to pursue leisure and other personal goals that distract from parenthood.

“The drive to leave a legacy through offspring can be side-tracked by an attraction to legacy through other things like career, fame, and fortune – distractions that, until recently, were only widely available to men”.

Dr. Aarssen speculates that the now widespread incidence of childlessness in developed countries will subside, not because of cultural evolution but because of biological evolution.

The women who leave the most descendants will be those with an intrinsic drive for motherhood. The ones who would rather forego parenthood in order to have a career, lavish vacations and leisurely lifestyles will of course leave no descendants at all. Over time those genetic traits that influence women away from motherhood will necessarily be ‘bred out.’

In this way future generations of women will inherit a stronger genetic predisposition for mating and having children as a priority in their lives. Dr. Aarssen predicts that an increased desire for marriage and having children, in both men and women, will be an inevitable product of evolution within the next few generations.

“The bottom line from a biology viewpoint is: in order to have your genes live on, you’ve got to have kids. If you don’t, then they’re going to disappear,” says Dr. Aarssen.

- Queen's University