How did my genes survive?

What can shortness tell us about evolution?

     Short people got no reason
     Short people got no reason
     Short people got no reason to live
       --Randy Newman

Last year, journalist Miriam Fauzia wrote,

Even though the average height of men in the US is 5’9”, many people state in their dating profiles that their prospective date must be at least 6 feet tall.

I am 5’3”. I wonder why I exist. If the preferences that women express on online dating sites are to be believed, then if I were young and single then my chances of reproducing would be close to zero. Working backwards, the genes that caused me to be almost two standard deviations below the mean for males should have been culled long ago.

One possibility is that male shortness appears often even though very few short males reproduce. Tall males can produce short male offspring either because of mutations or because they mate with short females (my mother was 4’11 and my father was almost a foot taller).

Genes that reduce survival chances in some environments may increase survival chances in others. For example, some environments favor risk-taking while other environments favor caution, so nature makes sure that some people have genes that make them adventurous while other people have genes that make them cautious.

Maybe not every environment favors tall males. If we lived in an environment in which a male’s chances of reproducing depended on being able to survive the middle seat of an airplane, I would have an advantage.

But I prefer to think that the fitness of short males is not as weak as the dating apps would make it appear. Fauzia offers this anecdote:

“I’m a rather short woman in real life who doesn’t have a height preference for guys that I meet in real life,” Sabrina K. wrote BuzzFeed News in an email. “However, on dating apps, I do see myself wanting taller men. I know I don’t care for it in real life, but on dating apps I do … [because] profiles are not that detailed, and there’s nothing much to care about when swiping for men.”

It sounds as though dating apps are steering women toward up-weighting their preference concerning height.

The woman who became my wife was initially attracted to me because she liked my friends. My guess is that dating apps do not make it easy to advertise “I have nice friends,” nor do they make it easy for women to realize that having nice friends is important in a partner.

Joseph Henrich and others believe that the gene pool is affected by culture. For example, Richard Wrangham believes that humans “self-domesticated” in comparison with chimpanzees by culling the most violent members of our species.

I would speculate that for many generations, evolution did not care much about your IQ. In the past few hundred years, with modern culture, IQ began to matter more. That is my story for the Flynn Effect.

Similarly, I would speculate that for many generations, evolution may have cared a little about a man’s height, but not as much as women do on dating apps. But going forward, with dating apps holding sway, men of my height will be less likely to reproduce. In other respects, we may be more fit than other men, but in the world of online dating women will be too superficial to find out.

This essay is part of a series on human interdependence.