Why do roosters always crow at the same time every day?

When we think of roosters, the first image that comes to our mind may be of them raising their heads in the morning light and crowing. However, you may still be misunderstanding the reason why roosters crow at the same time every day!

Rooster crowing, the mystery of nature

The act of roosters crowing at dawn has become a familiar rule in nature. This seemingly simple question not only arouses curiosity but also makes scientists spend many years researching to find the answer.

It wasn't until 2013 that the answer was revealed. Through experiments by Japanese biologists, it was discovered that the crowing of roosters in the early morning is closely related to the secretion of hormones combined with the effects of light. In the rooster's brain, the pineal gland – the organ that secretes the hormone melatonin – plays a major role in controlling biological cycles, including sleep and wakefulness.

As darkness falls, the pineal gland secretes melatonin, but at the first light, this process is inhibited. At that time, the sudden change in melatonin levels stimulates roosters to crow. This suggests that roosters' crowing behavior is governed by their circadian clock – a mechanism regulated by hormones and light.

The role of biological rhythms

It is a common phenomenon for roosters to crow on time. However, why do roosters crow at a particular time?

In nature, many creatures are affected by circadian rhythms and roosters are no exception. Therefore, there is a close correlation between the rooster's circadian rhythm and its crowing behavior at specific times.

Circadian rhythms influence the rooster's ability to assert its territory, hormone levels, and light perception to initiate and stop crowing behavior at the appropriate time. These circadian rhythms are not only a natural manifestation of rooster behavior, but also provide important clues to our understanding of how organisms adapt and evolve to their environment.

Roosters crow to mark their territory and challenge other competing roosters. However, roosters do not crow continuously, but become more active in the hours before dawn and stop crowing about two hours after sunrise. This is because the rooster's circadian rhythm causes them to become more alert and excited before dawn in preparation for competing with other roosters for territory.

In a study, scientists found a significant relationship between the time roosters crow and the altitude of sunrise. Specifically, roosters crow 10 to 15 minutes before sunrise. This is also the time when roosters crow the most during the day. Since then, crowing on time has become a rule. In addition, temperature, sound, environmental, social factors, etc. will also have a certain impact on the rooster's biological clock. (Photo: Zhihu).

Circadian rhythms also influence hormones in roosters. During the hours before dawn, roosters' oxytocin levels gradually increase. Oxytocin is a hormone that promotes active behavior and crowing in roosters. This process is jointly regulated by the rooster's internal biological clock and external environmental factors. As the sun rises, the amount of oxytocin secreted gradually decreases, which is one of the reasons why roosters stop crowing after sunrise.

In the natural environment, roosters determine when to crow by sensing the presence and changes in light. Although roosters do not have the ability to perceive bright light, they can sense differences in light intensity. As the light increases, roosters will gradually increase the frequency of their crowing and gradually stop crowing as the light becomes brighter. This circadian control of rooster crowing behavior is based on biological evolution and adaptation to the rooster's environment.

Circadian rhythms affect the rooster's ability to assert its territory, hormone levels, and light perception to initiate and stop crowing behavior at the appropriate time. This circadian rhythm is not only a natural manifestation of rooster behavior, but also provides important clues for us to understand how organisms adapt and evolve to their environment. (Photo: Zhihu).

Territorial claims and social communication

The territorial assertion of roosters is one of the main reasons why they crow on time. Roosters are endowed by nature with a certain sense of territory and they crow to declare their territory.

Every morning, the rooster will stand in the middle of the territory, raise its head high and crow loudly to warn other roosters not to invade its territory. This sound can be transmitted very far, reminding other fighting cocks not to cross the boundary.

By crowing, roosters can identify other roosters in their territory and interact socially with them. Roosters use different crows to express different emotions and intentions, such as declaring their dominance, attracting individuals of the opposite sex, or challenging other roosters. Therefore, crowing on time is also an expression of social communication.

Chickens are highly social animals and crow to communicate with other roosters. A rooster's crow can convey different messages, such as warning, courtship, and fear. Crowing on time in the morning is a signal for roosters to start their work for the day and is also one of the ways they communicate with other roosters. (Photo: Zhihu).

The timing of a rooster's crowing is also closely related to its sexual maturity. Roosters typically reach physical maturity at 5 to 6 months of age. Sexual maturity means that the rooster's reproductive organs are fully developed and capable of reproduction. When roosters reach sexual maturity, they will begin to display territoriality, announcing their presence by crowing - a rooster's crowing can convey its strength and leadership status, while also attracting the attention of hens.

As diurnal animals, roosters have a strong biological clock. They crow punctually in the morning, which is likely a pre-sunrise habit in the wild. The crowing of roosters helps them determine the time before sunrise and acts as a kind of stopwatch for their biological clock. In this way, they can accurately predict and adjust their circadian rhythm to daily changes in the environment. (Photo: Zhihu)

Looking for food

In addition, crowing is also related to the need for survival. With poor eyesight at night, roosters wake up early to search for food at dawn - the time when insects appear in abundance. When they find a food source, they will crow to call the hens.

From asserting status, attracting mates to searching for food, the crowing behavior of roosters is not simply a sign of dawn but also contains many important biological meanings.