Seoul is a mountainous city. People who visit the city for the first time rarely miss to comment on the mountains around. But people like me, who grew up in the city without knowing other parts of the world, hardly find it special. For me, the realization came a lot later after visiting a few big cities, such as New York, Tokyo, Bangkok.

Because Seoul is in the middle of mountains, hiking is one of the most popular activities for us. And it must be one of the reasons why those eco-friendly bike-ride campaigns almost always fail: To ride a bike in the city means riding a mountain bike.

And that is also the reason I used to have pheasant neighbors when I was growing up. I grew up in a district called Gangnam—yes, from the song. Back in the 80s though, the place wasn’t much about hipness; streets weren’t paved yet and in fact, there weren’t many streets. There were a few buildings, but so were cabbage patches. So were trails crossing the patches; so were villagers working on the patches; so were forests and big trees hugging all those sceneries.

So I guess it wasn’t a bad place not only for children like me, but also for wild animals. And food from people like my parents must have helped them too. In winter, my parents would scatter soybeans in a forest nearby, worrying the pheasants couldn’t find food in snow. And as a child, what else would you do? Stay quiet and wait, until they appear.It was a long time ago and I don’t have much memory about it, but there is one thing that has been stuck in my mind; A cock was always a colorful, splendid one whereas a hen looked rather plain and humble. 

About twenty years later, I happened to learn the science behind it. According to evolutionary biologists, in many bird species, a female bird ‘judged’ her mate by his feather. Peahens are attracted to peacocks with rich and symmetrical feathers. And studies revealed that the peacocks with the ‘popular look’ had a stronger immune system. While hens are attracted to the male birds’ physical attributes, it is in fact their instinct seeking healthy genes.

The similar tendency is found in human studies too. A study showed that babies as young as 3 months old gaze longer at pictures of faces with more proportional features. And they, the ones with a popular face, turned out to be healthier gene holders.

Men are attracted to women with 0.7 waist-to-hip ratio and studies revealed 0.7 women are most likely to have a child. Glowing skin means healthy skin, and shiny, bouncy hair is a sign of good health for a long period of time. Women generally prefer big, dependable men and it’s not hard to imagine the strength and dominance of a man actually meant better protection and a higher survival chance, at least in the past.

These all implies physical attraction is not so much about form as it is about function.

Then why does this beauty-health connection exist? Why does healthy genes of opposite gender just ‘pops out’ in our eyes even without conscious thinking?

In all of human history, the amount of time we humans have dwelled in cities is just a brief moment. If we imagine three million years of human history as taking up one year, the amount of time we have spent in cities makes up just over one minute. Except that one minute, we spent the whole year in a harsh, deadly environment where, sometimes, it was miraculous to make it to the next day. In a hunter-gatherer society population stayed steady. Death usually balanced reproduction, which means not all of our children could survive. Human population skyrocketed only after we started farming. Before, whoever not ‘enough’ to overcome the hurdles of the environment could not make it and pass their genes to the next generation.

Then what kind of body would have been enough? It must have been able to walk long to forage, carry heavy things such as game, climb up trees to gather fruits; it must have been strong enough to protect babies and fast enough to hunt or avoid being hunted.

And even if they passed the survival games, it wasn’t the end of the story, at least for the genes. If they somehow got attracted to unhealthy mates and gave birth to a child not as capable, the genes might have failed to be passed on somewhere down the road. It was only when survivors recognized and mated with a partner with healthy qualities, the child would have a good chance to finish his own journey successfully.

As the screening process has been repeated throughout hundreds of thousands of generations, the gene pool shapes itself with healthy beings with the healthy-gene-seeking preference. If a man is attracted to a woman’s 0.7 waist-to-hip ratio because of its higher chance of fertility, the gene pool would soon be filled with women with the ratio and men who are attracted to the ratio. That’s why once people get fit and recover the look they are supposed to have, they inevitably become better-looking to opposite gender.

This understanding that beauty is rather a byproduct of health makes us gym-goers’ job easy because it means if we go for a healthy, well-functioning body, beauty will follow.

In this perspective, we can see how modern beauty and health industries contradict themselves. They seem to turn a blind eye to the link between health and beauty. Cosmetics and plastic surgery professionals stress becoming beautiful, but not healthy; Nutrition companies and East-Asian medicine gurus lecture on health, but not beauty.

Beauty is a sign of health and whatever gets you healthy, strong and functional will inevitably make you beautiful.

Louis Sullivan, the father of modern American architecture, coined the famous phrase: “Form follows function.” It seems to apply to our body as well.

<Further readings>
– “We are descended from only those people who sought the best genes, a habit we inherited from them. Therefore, if you spot somebody with good genes, it is your inherited habit to seek to buy some of those genes; or, put more prosaically, people are attracted to people of high reproductive and genetic potential—the healthy, the fit, and the powerful.” Ridley, Matt. 1993. The red queen: Sex and the evolution of human nature. New York: Harper. p. 14.
– Beauty detectors scan the environment like radar: we can see face for a fraction of a second (150 sec. in one psychology experiment) and rate its beauty, even give it the same rating we would give it on a longer inspection. Etcoff, Nancy. Survival of the prettiest: The science of beauty. New York, Anchor, 1999. p. 7.