Washington : Roosters crow at the break of dawn, not in response to the morning light, but because they are genetically programmed to do so, a new study has found, reports PTI.
Until now, it has not been known that when roosters crow with the dawn, are they simply reacting to the environment, or do they really know what time of day it is? The study published in journal Current Biology, found that a rooster’s crow is controlled by its own internal body clock and does not depend on lighting conditions.
“‘Cock-a-doodle-doo’ symbolises the break of dawn in many countries. But it wasn’t clear whether crowing is under the control of a biological clock or is simply a response to external stimuli,” said Takashi Yoshimura of Nagoya University. To find out more, Yoshimura and his colleague Tsuyoshi Shimmura placed birds under constant light conditions and turned on recorders to listen and watch.
