Ok, so what’s the basic biological feature that makes it such that women need to attract males but in other species, males need to attract females? Is it something about our long infancy period, the needs of women to have a protector around for a long childhood?
It hasn’t yet been shown that the majority-female use of cosmetics over the course of known recorded human history actually has a biological or evolutionary cause, rather than a cultural/historical cause.
The cause may be biological, of course, but as I remarked above, we can’t disentangle biological from cultural factors well enough in either modern or historical human societies to be certain of that.
For example, the predominance of females in the use of cosmetics, as other posters have pointed out, is very likely related to the patriarchal structure of most human societies. That is, unlike in many other species, among humans the behavior of females has been largely controlled and regulated by males, so a female’s status has been determined primarily by the male sexual attraction she can inspire. And cosmetics, as previously noted, are chiefly about inspiring sexual attraction.
But why has the default social structure for humans in the historical period been patriarchal in the first place? Is it necessarily hard-wired by evolutionary biology, or might it be just the way things happened to work out in the culture of the relatively few survivors of a population bottleneck before the global human diaspora, and then persisted in subsequent societies due to cultural inertia?
We don’t know, and it’s not certain that we can know. But if we don’t know, there’s no point in telling ourselves evolutionary-psychology “Just So Stories” about how human evolutionary pressures produced majority-female use of cosmetics. It’s not certain that evolutionary pressures were actually the cause of this phenomenon.
The Wodaabe of Niger have traditional beauty contests of young men involving costumes, makeup, beguiling smiles, crossing their eyes, and their legs being tied together at the knees for days. It’s judged by the old women.
So unbelievably cool.
It seems to me that this latter pose is closer to a “just so” story. I believe that underneath a large number (most? all?) cultural features, one can find some sort of biological function that underlies them. Remember that Pinker even suggests that culture, itself, is essentially a biological and naturally occurring feature of our species. I think that the preponderance of female adornment has some roots in our ancient history and that it’s fundamentally related to sexual selection. I just can’t quite see the rationale. But that’s mainly because I know so little about the topic.