It's Valentine season, and children everywhere are celebrating friendship and love by giving cards and candy to their friends. In what alien observers must consider one of the most bizarre human customs, these same children are being asked to draw lewd pictures of human private parts. You don't think you or your children participate in this custom? Take a look a the figure below...
I thought you might recognize it. It's the Valentine heart, of course. But what you may have failed to consciously notice -- and what gives the alien observers the giggles -- is that the Valentine's heart is not just some arbitrary red double-humped shape. Rather, the Valentine heart is the human rump -- the red, engorged, upturned human rump. You've seen too many Valentine hearts to believe me at this point -- and, sadly, you have probably seen far too few red, engorged upturned human rumps -- so I encourage you to make your own field observations and verify.
Because this is a (somewhat) family web site, rather than showing you the flushed upturned rump of a human female, I have placed the flushed upturned bum of one of our close cousins below.
I'm surely not the first to have noticed the rump-like look of the Valentine heart, but I'm surprised how long it took me to notice. You see, I have an uncomfortably tight history with the primate rump -- if you do a Google search on primate rump you get ME! Try it. The article of mine that comes up concerns how our primate variety of color vision may have evolved in order to sense skin color changes like those found on bare primate rumps. How could I have missed the Valentine rump? And now that I've noticed it, though, I can't shake it! My wee children exchanged Valentines with their school friends, and rather than seeing sweet cards, I can't help now but see each heart as a case of NSFW anime porn!
The most characteristic symbol of Valentines -- symbolic of love -- is a red engorged raised rump, right under all our noses. But, one might object, the history of the Valentine symbol is complex, and although no one is quite sure of its origins, it seems quite implausible that it was coined with engorged female buttocks in mind. Indeed, engorged bums may have been the farthest things from the minds of the Valentine heart originator, but that does not mean that the Valentine heart might not nevertheless be about female rumps. Gobs of symbols were invented throughout history, and many may have been coined for symbolizing love. But only a tiny few have legs. Those that survive were culturally selected for, and their reason for surviving may have no relation to the reason they were originally conceived.
Valentine hearts may have been culturally selected for over time because of their similarity to engorged rumps.
In an earlier piece I discussed research of mine concerning how writing has come to be shaped "like nature" via cultural selection over time. Writing thereby taps into, or harnesses, the power of our visual system. Although not quite as life-changing as our ability to read, Valentine hearts tap into our visual system as well, looking like something quite natural, and eliciting passion in the viewer.
So next time you see someone drawing a Valentine, say "Shame on you!"
Mark Changizi is Director of Human Cognition at 2AI, and the author of The Vision Revolution (Benbella Books, 2009) and the upcoming book Harnessed: How Language and Music Mimicked Nature and Transformed Ape to Man (Benbella Books, 2011). An earlier version of this piece was originally posted in 2010 at my Science20 blog.