Stroke me, I’m a primate: our need for human touch

Now more than ever, we need to touch each other.

Dr. Nina Jablonski, a primatologist, evolutionary biologist, and paleontologist, is professor and head of anthropology at Pennsylvania State University. She kicks off Saturday at Pop!Tech with a talk on the meaning of human skin, the subject of her book, Skin: A Natural History.

She starts by noting what “a phenomenal and exceptional group of primates” she has for an audience. She asks each of us to look to his or her neighbor, and touch for about 20 seconds. She suspects that some of us haven’t done much touching this morning; she worries that we are too wired, surrounded by our cell phones and technology to even think about the great emotional power of the human touch. She says that we’ve lost the capacity to observe each other, and wishes for a return of times when we did more things of this kind.

We primates are highly observant animals, she says. It’s in our nature to touch each another, inspect each other, learn through observation. Our main sense, the sense which we depend on most for our information gathering, may be vision, but the second is touch, equal with hearing.

Our great touch-organ, the skin, helps us gather an enormous amount of information from and about our environment. Some of our most sensitive skin is on our hands, equipped with nerves that detect pain, touch and temperature. Jablonski shows a picture of a cartoonish creature she calls “the human sensory homunculus,” whose body parts are proportional to their skin sensitivity. Hands are the biggest part of the body; lips and tongue also quite come close.

As primates, our instinct is to touch one another quite a lot, she says. From the moment of birth all primates start to engage in very detailed types of touching with their mothers. She cites an experiment from the early 1960s, conducted by a psychologist called Harry Harlow, who took baby monkeys away from their mothers and put them next to two mechanical surrogate mothers. One “mother” was soft, had some sort of a pillow attached to it, but had no milk. The other was made up of wires only, but it did have milk.

The baby monkeys spent all of their time with the “milkless mother”, and made only very short trips to the wired one to get fed. The reassurance and warmth of the “milkless mother” was more important.

There are other ways in which primates use touch. One of them is to to cement alliances. Jablonski presents a picture of two chimpanzees who are touching each other trying to patch things up and get over their arguments.

Grooming is incredibly soothing, says Jablonski. The participating animals both gain a tremendous amount of relaxation. Their levels of stress hormone both decline. We humans pay a lot for grooming, although we may not call it such: think of the spa massages and facials given to us by complete strangers.

Jablonski observes that when we touched each other just now, at her request, we must have noticed differences in one another’s skin color, from very light to very dark. This is a function of the skin pigment, melanin, of which we have different amounts. She shows a drawing of a man holding his skin in his hand, as if it were his clothes. “Stripped of skin, we are all alike”, she says.

5000+ years later we can still see Ötzi’s many tattoos. This cross was found on his knee.

We may also have noticed that the person sitting next to us uses cosmetics or has a tattoo. We like to decorate ourselves. “Humans are self-decorating apes”, jokes Jablonski. Cosmetics are used to highlight certain features, particularly the ones thought to be sexually attractive. Tattoos appear for a variety of reasons, but usually to signify something we think important, so much so that we want to make it permanent, on the surface of our bodies.

It’s worth noting that none of this is a recent phenomenon. We know from the study of classical and pre-classical Egypt that the cosmetics industry existed for many years there, particularly in the area of eye-shadow and eye-liners. An ice man (Ötzi) with tattoos was found in the Tyrolean Alps, where he had been preserved for more than five thousand years.

Concluding her talk, she appeals to us to think more often about our skin, and about how we used to communicate with each other by touching. For generations we lived in groups like that were in constant contact with one another—and that contact was physical rather than electronic.

So how come we do so little of it now? Jablonski blames the lawyers. “America is a touch-averse society, mostly because of the layers of litigation that have come to prevent us from touching in most public spaces and in the work place”, she says.