Originally a piece in ScientificBlogging, October 2, 2009…
Dear Hugh Hefner:
Ever wondered why you’re rich? Yes, yes, you’re a savvy businessman who succeeded where thousands have failed. But there are deeper reasons underlying why your business model works at all. When one digs deeply enough one finds that color – yup, the stuff of rainbows and Crayola – is at the core of your success. Without hue, there’d be no Hugh.
To see why you should be giving thanks to the existence of color, let’s start with something closer to your home; nakedness. Although mammals tend to be furry-faced, some of us primates had the chutzpah to lose the hair on our faces, and often on our rumps. And we humans are nearly naked all over, something you may have noticed. If we humans weren’t so bare, we would probably not wear robes. And then there would be no reason to disrobe.
If there were no bare skin, there would be no Hefner as we know it.
Now let’s delve deeper and ask why some of us primates got bare in the first place. One feature that distinguishes the primates with bare faces from the furry-faced ones is color vision. The naked primates can see in color, but the furry-faced ones cannot. Color goes with nudity. Why?
As I have argued in my research, our color vision is a distinctive kind of color vision, one that is specialized for detecting the color changes that happen in skin due to the physiological changes in blood (e.g., oxygenation). Most varieties of color vision – like that in birds, reptiles and bees – do not have this extraordinary capability. Our color vision is for seeing blushes, blanches, red rage, sexual engorgement and the many other skin color changes that occur as one’s emotion, mood, or physiology alters. Color is for seeing embarrassment, fear, anger, sexual excitement, and so on.
Our primate ancestors once had furry faces, and one was born with our style of color vision, able to detect the peculiar changes in our underlying blood physiology. Although the faces this ancestor looked at were furry, some skin would have been visible, such as around the eyes, nostrils, lips and any lighter patches of fur. This ancestor would have been born an “empath,” able to see the moods of others. Color vision of this kind would thus spread over time.
And once it spread, animals could then have evolved to “purposely” signal colors indicating their mood, and then bare skin would have evolved to have more canvas for signaling. Many of our skin color changes are indeed “purposeful,” i.e., not simply inevitable consequences of our underlying physiological state. For example, Peter D. Drummond has shown that peoples’ faces blush more on the side which people can see.
You might be wondering why, unlike the other primates who mainly have bare faces and rumps, we humans are so naked all over. It might be that, although we don’t consciously notice it, we color signal over our entire canvas. If all our bare spots are for color signalling (setting aside the palms and the bottoms of the feet) then we should not be naked in places that viewers would not tend to be able to see.
Well, there are three places on the body that are difficult to observe; the top of the head, the underarms and the groin. And notice that, as expected if bare skin is for color signaling, these three spots are the universally furry spots on humans.
The only complication here is that the groin does occasionally become dominated by bare skin rather than fur, namely when the genitalia engorge. But at these times there is often another person involved in a behavior wherein the groin is, ahem, no longer difficult to see.
Bare skin really may be for looking at! And it is worth looking at because it often signals something to the viewer. But the viewer can only see these signals if they have our special kind of color vision.
No color vision, no nakedness. No nakedness, no Hugh Hefner.
Or, no hue, no Hugh.
And now the real point of my writing: Because of the dependency of your enterprise on the evolution of color, it would only be natural to bring some diversity to those apocryphal parties at the mansion … by inviting an evolutionary neuroscientist.
Just have your people call my person.
Mark Changizi is a professor of cognitive science at Rensselaer Polytechnic Institute, and the author of The Vision Revolution (Benbella Books).
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