Why Do Roosters Crow?

If you happened to visit a farm or live nearby a farm that has a rooster coop, then you are most likely to get awakened by a rooster. This started to get some researchers curious about why roosters crow at certain points of the day. Scientists didn’t know whether roosters knew the time of day or if they were just faking it. Japanese researchers Tsuyoshi Shimmura and Takashi Yoshimura have figured it out.

This long experiment took a whole two days to accomplish. They first placed three groups of four roosters in different sound proof rooms. Then, they gave them twelve hours of normal light and twelve hours of dim light. After that, they gave the roosters 24 hours of dim light. None of these tests fooled these brilliant roosters, they crowed at exactly the same time every day. The scientists still wanted more so they put the roosters through one more test. This time they added noise to the lights to see if that would fool them. They still crowed at the exact same time.          

Studies show that rooster’s crow in the morning to protect their territory, feeling threatened, or just communicating with other roosters. They have an internal circadian clock which is a rhythmic biological cycle, that cues them every morning to know when to crow at the same time. They crow to warn other roosters early in the morning to make sure they don’t come around their coop. 

http://www.dogonews.com/2013/3/23/researchers-solve-the-age-old-mystery-of-why-roosters-crow

http://blogs.nlb.gov.sg/ask/children/1174