Body scent attractiveness, climate change, and love poetry

From an NYT article on product differentiation in the online dating industry:

Consider ScientificMatch.com, founded about two years ago, which aims to create romantic chemistry via genetic testing. The site, which matches people based on certain genetic markers for the immune system, takes its cue from studies showing that women are more attracted to the smell of men who have very different immune systems from their own. The site charges $1,995.95 for a lifetime membership -- the lofty fee includes a cheek swabbing kit, DNA processing, a criminal and bankruptcy background check, as well as verification of age and marital status, the site says.

I have a more cost-effective way to find out which men smell better to you -- go to a gym, bar, dance club, or other place where there are lots of people giving off lots of odor. Now can I collect my billion dollar investment from a venture capital firm?

The company's website plays up the sweaty t-shirt studies, where evolutionary psychologists show that people are more attracted to the smell of t-shirts from others who have very different immune system genes. The idea is that by mating with someone who is different, the combination between you and your mate will be close to novel. In this way, pathogens will have a harder time figuring out how to infect your children -- if their genetic profile were one that already existed, they'd already know how to pick that lock. It's just an extension of the Red Queen hypothesis for why there is sexual reproduction at all.

Certainly if you planned to use online dating sites to find someone to have children with, having the genetic data would give you a more accurate estimate of how different your immune system genes were. However, few are interested in that, as shown on the company's website. They emphasize all of the child-irrelevant perks like finding your partner's smell more appealing, having a greater chance of female orgasm, and so on. It's clearly for daters rather than aspiring parents.

The trouble with that is that most of these studies are done on college students. For those who don't remember, teenage and college girls smell wonderful. The 30+ women who these genetic screening services are aimed at do not give off powerful pheromones like the young girls do. Because there is low ceiling on how intense older women's scent can be, the magnitude of these effects is going to be very small. The same goes for orgasming: it's not uncommon among college girls, but pretty rare for 30-somethings and beyond (lower hormone levels). Even if genetic screening ensured that the woman would derive the maximum benefit, it still wouldn't amount to much because the ceilings are too low.

By the way, I noticed at the most recent '80s night that a lot of the 18-20 year-olds have already begun to produce their powerful ovulation aroma. Last year, it wasn't until around March 20 that this happened. We had a much longer, colder, and snowier winter last year. This year, there's hardly been anything, and it's been mild enough during the past week that I could comfortably go out in an undershirt and sweater -- no coat. The more I think about it, the more it looks like human females really do have a mating season that responds on-the-fly to the weather. If it seems like there's going to be a harsh winter, their pussies go into hibernation. If not, they just rest it out for a little bit before concluding pretty soon that it's safe to come out and play. There's another reason to welcome global warming.

I wonder if we see this in history -- there was the Medieval Warm Period that saw the flowering of the courtly love and troubadour traditions. Something was getting those guys awfully worked up. Here's a graph of annual temperature over the past 2000 years. We'd predict hormone-governed love poetry to hit a nadir during the 17th C. during the Little Ice Age. Shakespeare's love sonnets are an exception in that century. I recall the rest of that period from my freshman English class as being much less raw and lusty, culminating in the work of metaphysical poets like John Donne. I rather like those elaborate conceits, but they sure don't pack the punch of troubadour-era songs.

We'd also expect highly hormonal love poetry to start coming out of hiding toward the end of the 18th C. and certainly by mid-19th C., when temperatures began climbing again. That's more or less when the Romantic movement broke out all of a sudden across Europe, followed by other losing-sleep-over-girls movements like the Pre-Raphaelites. Something about females started driving guys crazy again, and I'll bet it was a return to the warmer temperatures that allowed men, for the first time since Bernart de Ventadorn, to enjoy the ovulation scent nearly year-round. And of course the love song has only exploded further in popularity during the warm 20th C.