While working alone in an otherwise quiet house yesterday afternoon, just as the sun was setting, I was surprised by the sound of a cockerel crowing from the living room. Baby Iris has a toy puzzle with different farm animal shapes, and it uses tiny light sensors to detect the presence or absence of the pieces. It plays the animal sound as each piece is put in the correct hole. As is usual in our house, the pieces were scattered around the room, none of them in their little holes. The setting sun lowered the light levels bit by bit, and the cockerel was the first to sound. A menagerie of farm animal noises followed as it got darker and darker, but I was struck by the bizarre electrical inverse of a real cockerel crowing at the sunrise.