I was on an internal flight to Florida a few years back. Someone had a small parrot in a travel cage with them. It escaped when we were at cruising altitude and it flew the full length of the cabin then perched on the back of a seat near me. It was harmless but the terrified reaction of some passengers was surprisingly hilarious. One chap wanted it put off the plane! Another claimed he would now get bird 'flu and would be suing the airline. Another one almost dived to the floor. All grown men...at first glance, anyway.