There was this study that I can't find right now and if anyone has it please share it where they found that around the world, in different cultures, men with long hair are, on average, seen as sexier by women. However, the men usually have it short because it's very impractical to have it long. For example some tribes in rainforests were studied and the men cut their hair because that made fighting and hunting easier (you don't want to have a mane that other fighters or animals can pull from), but the women indeed found long hair more attractive. So this would be a case of What is sexy vs What is practical, which aren't always the same thing.

Does anyone have that study? It was shared here a while ago but I can't find it right now. Thanks in advance.

This duality of sexual selection (selecting partners based on what makes us horny) vs environmental selection (selecting partners based on who's still alive because those who weren't fit for the environment are dead) appears in numerous other species across the animal kingdom. Even in humans it's present: it is estimated that blue eyes in humans only appeared between 20.000 and 50.000 years ago and they only appeared by mutation in a very small group, some studies say it might have been one single person. And yet blue eyes spread across the Earth to the point millions and millions of people have them. Do blue eyes see better? Nope, they're normal eyes. Do they see in the dark? Not at all. Are they more resistant to ultraviolet radiation or something? No.

They're just pretty. That's entirely their appeal: they don't do anything that other eyes don't. On a practical level they don't make any difference, but on the level of sexual attraction blue eyes are widely regarded as the most beautiful.

It's like in some species of birds where the males with the longest and brightest feathers are the most popular among the females but those guys die early without offspring because their feathers are dysfunctional and they can't fly/run fast enough so predators eat them easily. The same was found about the coloration of fish, the fur of mammals, etc; what's "sexy" is not always what makes it into the next generation.

Same for the hair example that I gave you: any form of long hair is a disadvantage against opponents both human and animal. Even if the man ties his hair in a bun, that's a perfect handle to grab and pull from. Hygiene also plays a role: shaving your head, armpits and privates does indeed prevent many diseases and parasites and makes washing easier, preventing infections. That's why egyptian pharaos shaved everything.

So in a nutshell: everyone wants to have babies with Person X but then Person X dies because the traits that made them sexy also made them vulnerable to other humans, to predators or to diseases. So people have to put up with whoever is still alive; they're not sexy, but their traits are practical and that's why they're still alive.

What about you? What traits do you think might be found attractive but are horribly impractical or at least just useless?