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Everything We Know About Human Bathroom Behavior

...Men must abide by tons of unwritten rules. One academic codified the etiquette this way: “Do not stand directly next to another man at another urinal.” “Do not look at another user during urination, and, if possible, keep conversation to an absolute minimum.” “If you shake it more than twice, you’re playing with it.”
Men get pee-formance anxiety; women, not so much. There are two social phobias men have at a much higher rate than women: returning something to the store, and peeing in a public bathroom. And the closer men are to another person, the longer it takes them to get the flow going: In one study, the authors monitored a row of three urinals and clocked an average of 4.9 seconds if the subject was all alone, 6.2 if there  was a one-urinal buffer, and 8.4 at close range...