Cornell graduate student Michael Smith studies honeybees. The day he was stung on a testicle inspired a new experiment: what body part hurts the worst when stung by a bee? Mind you, if the testicle sting had been particularly painful, the rest of the experiment would have never been carried out. But since Smith was surprised at the relatively low pain of a testicle sting, he laid out a plan to test other body parts. Understanding the difficulty of enlisting subjects in this kind of research, he only ran trials on his own body.
Smith was methodical. He collected bees by grabbing their wings “haphazardly with forceps” and pressing them against the body part of choice. He left the stinger there for a full minute before removing it, and then rated his pain on a scale of 1 to 10. Pain is very hard to measure, but psychological studies have found that numerical scales do a decent job of putting numbers on an inherently subjective experience.
He administered five stings a day, always between 9 and 10am, and always starting and ending with “test stings” on his forearm to calibrate the ratings. He kept this up for 38 days, stinging himself three times each on 25 different body parts. “Some locations required the use of a mirror and an erect posture during stinging (e.g., buttocks),” he wrote. If you are chuckling at the image of a man twisting around in front of a mirror to apply an agitated bee to his butt, I assure you that you are not alone.
Smith determined that the worst place to get stung was his nostril, followed by the upper lip and the penis. The least painful sting was on the skull. Ed Yong has more painful and droll details about the experiment at Not Exactly Rocket Science, and the comments have additional details from quite a few beekeepers who tell various stinging stories.