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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  • nightwaves
    nightwavesabout 2 years
    Pretty Cool!
    • wolfy_blue
      wolfy_blueabout 2 years
      Wow. that's pretty cool.
      • Silverstreamover 4 years
        This is not at all accurate! Both my roosters crow all day, off and on. They don't crow early in the morning, but as the afternoon comes on. They tend to crow more in the warmer months. Although these months do have more sunlight, they start way after the sun comes up. Also, even in the colder months, like winter, they only crow when it starts to warm up. Like today for example my rooster Dillon has been crowing all day, while yesterday it was rather cold he didn't crow once. Also, this article didn't state why they did it, just what triggers them to do it. I feel that roosters do it for territorial purposes, because my alpha rooster attacks my omega rooster when he crows.
        • Helpfulover 4 years
          This is an awnser to cat1321,we have rooster bc they are really helpful especially if you have to get up early there really annoying so you’ll get up!!!
          • Alexover 6 years
            It was very helpful in class
            • dogalmost 7 years
              i wonder why...
              • cat13121
                cat13121about 7 years
                why do we have them anyway they are to noicey at night and day
                • Poboyover 7 years
                  Hmmm. My rooster crows all day...
                  • mad_a_nn_78~almost 8 years
                    HI it is weird how the roosters have like a clock inside of them to tell when there are supposed to crow! This is a fun way to learn more of roosters and animals.
                    • nutcrackernerd
                      nutcrackernerdover 8 years
                      thats so cool!!!