Believe it or not, there’s still a lot we don’t know about roosters crowing even though, according to recorded history, they’ve been doing it since 2600 BC,.
We all know about the pecking order of our chickens – certain ones are the “top” in the group and tend to get to the food first or get to have the best roosting spot but according to a study published in Scientific Reports in July, the top ranked rooster is the first to crow every day.
Chickens are very social animals and the theory is crowing helps to announce their territory and avoid aggressive moves from other roosters.
Tsuyoshi Shimmura from Nagoya University in Japan studied groups of roosters and determined that the rooster highest in the pecking order determined when to begin the daily pre-dawn crowing with each rooster following after in order according to their rank. When the top rooster was removed from the group, the second in charge took over and filled his job, with each subordinate rooster, again in order, crowing next.
The timing of the crows is regulated by an internal biological clock, called the circadian clock. Although it can also be influenced by things like light and the crowing of other roosters, it’s mainly this 24 hour internal cycle that determines the time of the first crow each day. The scientists concluded that when in a group, roosters suppressed their own internal clock to accommodate the social rules of the group – in other words, the pecking order. So even though the second or third ranking rooster might feel inside “hey, it’s dawn and time to crow”, they won’t do it – not until the highest ranked has started the group off. The team also noticed that the highest ranked rooster crowed more often than the others.