mike@uhunix1.uhcc.Hawaii.Edu (Mike W. Burger) (06/28/91)
When I was into camping a lot, I noticed that the birds would all start up at once in what appeared to be "total" darkness. About 15 minutes later I could notice the greyness in the sky. I was always amazed at how the birds seemed to be able to notice the onset of dawn somehow before I could detect even the slightest greying of the sky. Also, they all seemed ready to begin and were just waiting for someone to jump the gun, then they all chimed in at once. Does anyone know how birds detect dawn? I did not think birds were particularly sensitive to light. In fact, I have seen some references that they do not see well in dim light, at least not as well as humans. Do they use internal clocks for anticipating dawn, reseting them each morning to allow for the drift in the time of the rising and setting sun? mike@uhunix.uhcc.hawaii.edu