That yogalike pose is known as a “play bow,” and in the language of play it’s one of the most commonly used words. It’s an instigation and a clarification, a warning and an apology. Dogs often adopt this stance as an invitation to play right before they lunge at another dog; they also bow before they nip “I’m going to bite you, but I’m just fooling around” or after some particularly aggressive roughhousing “Sorry I knocked you over; I didn’t mean it.”.
“If you have an exit in the middle of the wall, you can imagine coming from the left side, the right side, and straight,” Shiwakoti says. These different streams of ants, or people, have to merge at the exit and take turns to pass. But people are impatient, and start pushing and shoving. Columns help structure the flow. “The column gives you some channels on the left and on the right, and this reduces the conflict at the exit.” The reason the corner exit is so efficient, Shiwakoti says, is because it has an intrinsic ability to structure the flow. “If the exit is in the corner, then people are probably only coming from left and right, so you have a more uniform flow.”