Well, they never cease to amaze me. A few months back, I just left the main door (which contains the pop door) open for a few weeks during the day. The first day I closed it, all the chickens lined up on the ramp (that dead-ends at the pop door) wondering how to get in the coop. Finally, after about an hour, one decided to go through that 'strange new hole' leading to the inside. (You know... the one they were using for 4 or 5 months prior to me leaving the door open). All the others promptly followed. OK, the other day I was doing some routine maintenance in the coop with the main door propped open and one of my brightest girls came out of the coop, 2 or 3 steps down the ramp, and through the pop door which put her between the wall of the house and the coop door. If she went to school, she would ride the short bus!