Palm Perfume

Everyone knows what dogs do, immediately after they encounter another canine in a non-aggressive manner: they sniff each other's butt. (If it's an aggressive meeting, they growl first and then sniff butts.) Many other animals also smell each other out, although most of them do not directly head for the nether region. Odor is an ancient and effective way of checking out a critter that one meets. Is this an old acquaintance? Will I make friends with this dude? He looks pretty tough, but maybe it's really a sexually receptive “she.”

These are very animal-like behaviors. We humans like to believe that we are different. We don't need to stick our schnoz into each other's private parts to case out the newcomer. We look them in the eye to judge their character. We shake their hand and see how firmly they grip ours, or how long they hold on. Besides, our sense of smell is not all that good anyway.

Well, you can toss that belief into the trash, along with many other myths that humans are special and different—as I've posted numerous times on this blog. As it turns out, recent research in Israel and Germany has shown that people unconsciously sniff their right hand, just after shaking hands with another person. It's an unintentional maneuver, and thus an instinctual one. What researchers discovered—when participants were covertly filmed—was that people frequently brought their right hand near their nose, just prior to shaking hands, and then later held their hand near their nose for even a longer time span, after a hand shake.

But were they really sniffing the palm scent left by the other person, or in an absent-minded way just bringing their hand up towards their face? Like good scientists, the researchers installed nasal catheters up the schnoz of participants and, indeed, verified that they actually sniffed their hands, rather than simply itched their nose or inspected their manicure.

What's more, the chemicals transferred by the handshake were then lab tested. What did they find? Two chemicals: squalene and hexadeconoic acid; the latter is interestingly also known as palmatic acid. Even more fascinating: these chemicals are known to be some of the same ones that dogs look for, in their social butt-smelling rituals. The circle comes round: we are just like dogs.

So the next time you greet someone with a handshake, pay attention to what your right hand does, immediately afterward. Are you responding more to the firmness of their grip or the subtle palm perfume you subsequently whiff? Are you picking up more on the steadiness of their eye contact, or the subtle scent of their hexadeconoic acid deposited on your paw?