Michael Smith had a painful experience. A bee flew up his shorts and stung him on what is frequently considered (for men) the most sensitive spot on the human body: the testicles. That this happened wasn't a total surprise, since he studies honeybees at Cornell. "But I was really surprised that it didn't hurt as much as I thought it would," he told Ed Yong of National Geographic. Smith wanted to see if it was possible to measure how much it hurt to be stung on different parts of the body. So he coaxed bees into stinging him all over his body, multiple times. And it turns out the most painful place to get stung is not the testicles at all — it's the nostril. The experiment Smith chose 25 sting locations, from the skull down to the tip of the toe: Then he rated his pain on a scale of 1-10. "Average pain" (5) was based on an inner forearm sting. On each of the 38 days of the experiment, he was stung five times. The first and last stings were always on the forearm, and the middle three were rated in comparison to those. The side of the body that was stung did not change the amount of pain. Smith would select a guard bee (one that watches over the hive) from a cage each time, grab it "haphazardly with forceps," and hold it against the "desired location" for at least five seconds after pain was first felt. Then, he'd try to assess how much it hurt. Each body part was stung three times, so that scores could be averaged. For the most part, there was very little variation in how much stings to a particular location hurt. In the end, the most painful place to be stung was the nostril, followed by the upper lip and only then the penis shaft. The least painful locations were the skull, middle toe tip, and upper arm. These are the full results: Why bees? Honeybees are actually an ideal creature to use when measuring the pain of an insect sting. They were used as the basic point of comparison in the Schmidt Sting Pain Index, a project by entomologist Justin O. Schmidt that measures the intensity of the pain caused by 78 different insect stings. Stings are rated on that scale from 0-4, where a zero is a sting that cannot break skin, and a four is pain so intense that one of the few creatures whose sting rates that high is used in an Amazonian ritual that marks the transition from boyhood to manhood. The bullet ant, used in that ritual, causes hours of "pure, intense, brilliant pain," strong enough to trigger hallucinations. Honeybees, on the other hand, rate a much more manageable two. What this all means Smith notes that he was stung at least five times a day for three months before beginning the experiment, so his immune system should not have become more or less accustomed to bee venom over the course of the study. However, for ethical reasons, Smith only tested himself — so some of his results were obviously only relevant to men. And not only do men and women feel pain differently, but so does every individual. That means Smith's results can't necessarily be applied to the whole population. A "4" for one person could be a "9" for someone else. Even Smith's own pain ratings may have been affected by how much pain he expected to feel from each sting. But until someone else is willing to try (any takers?), these are the results we've got. Smith's study was published April 3 in the online academic journal PeerJ. Sting pain guru Justin Schmidt, among others, helped design the experiment. Source
