Researchers Solve The Age-Old Mystery Of Why Roosters Crow!


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If you happen to live near a farm or are one of those city dwellers that have a chicken coop complete with a rooster, you are probably used to being awakened by their customary crows at the crack of dawn. However, given that these birds also crow noisily at the slightest disturbance, made two animal physiology researchers wonder if the roosters truly knew that it was morning or, if they were just faking it. Curious to know what they discovered? Read on . . .

Tsuyoshi Shimmura and Takashi Yoshimura, both from Japan's Nagoya University first placed three groups of four roosters each, in different soundproof rooms into which they could beam varying amounts of light and sound.

They began by providing the three groups with 12 hours of normal light and 12 hours of dim light. Sure enough, all the birds crowed two hours prior to the normal light being switched on - similar to what they do outside, at predawn.

Then, the roosters were subjected to 24 hours of dim light. To the surprise of the researchers, this did not trick them out at all. They continued to crow at exactly the same time, indicating that it was their internal or circadian body clock that got them going, so early in the mornings.

Not satisfied, they put the roosters through one more test. This time, by adding noise to the shining lights to see if they could get them to crow at odd hours. However, the birds were smarter than that - While they crowed a little earlier than in the other two cases, it was still closer, to predawn.

The big lesson to be learnt from this scientific report that the two published in the March 18th issue of Current Biology, is that if you live in the countryside or happen to have a rooster in your backyard, you can safely toss your alarm clock out, for they will wake you up - Rain or shine!

Now that they have put this mystery to rest, the scientists are intrigued to solve other age-old mysteries, like why dogs go bow-wow and cats, meow meow! So, stay tuned!

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  • Dj_Sour_MilkThursday, September 26, 2013 at 10:24 am
    thats funny :)
    • chicken loverFriday, August 2, 2013 at 2:55 pm
      I have 4 roosters s. this is good information.
      • a_l_b
        a_l_bTuesday, June 25, 2013 at 4:14 pm
        That's cool now I know why rosters crow!!
        • NameThursday, June 13, 2013 at 7:18 am
          Someone in my family has Roasters and Hens.
          • blob bloobSunday, June 9, 2013 at 8:00 pm
            I going to a farm and buying a rooster
            • hiMonday, May 27, 2013 at 11:32 am
              I think that is awesome
              • i am a trollTuesday, May 21, 2013 at 2:04 pm
                welcome to planet earth
                • TROLLTuesday, May 21, 2013 at 2:04 pm
                  • meowTuesday, May 21, 2013 at 1:57 pm
                    that is really cool. Did they really say that there is a weird clock thing inside of them. That is really cool.
                    • emma5
                      emma5Monday, May 20, 2013 at 6:36 pm
                      Wow, what a great research idea, you would have never thought that those roosters would be so smart