Why can roosters crow on time? Does it have an alarm clock inside its body?

This question seems a bit ridiculous, because the crowing of a rooster is not the cause of the dawn, but a natural reaction to the dawn. The crowing of a rooster is a warning or notification of the dawn, and the rooster has no ability to cause the dawn at all. In other words, whether the rooster crows or not, the dawn will come...

The rooster's biological clock allows them to sense the coming of daylight. There is an organ in the rooster's body called the "pineal gland", which secretes melatonin and regulates the rooster's sleep-wake cycle. When daytime approaches, the secretion of melatonin decreases, which stimulates the rooster's brain and nervous system, causing them to start crowing.

In addition, rooster crowing may also be related to other factors, such as group behavior, territorial display or courtship, and may also have social and communicative significance among chickens.

The dawn itself is a natural phenomenon formed by the relationship between the rotation of the earth and the sun. As a planet in the solar system, the earth has a mass only 1/330,000 of the sun and is controlled by the sun's gravity. On the one hand, the earth revolves around the sun, making one rotation per year, and on the other hand, the earth rotates on its own axis, making one rotation in 24 hours, which is one day.

Because the Earth's rotation axis has an inclination of about 66°34' to the ecliptic plane, the angle of the sun's radiation into the Tropic of Cancer is different when it reaches different positions, thus forming the four seasons of spring, summer, autumn and winter. The Earth's rotation causes the side facing the sun to change continuously, thus forming day and night in the same place.

Since the earth rotates from west to east, the sun will rise in the east and set in the west in a certain place, and the cycle of day and night will continue every day. Even if it is cloudy and rainy and the sun cannot be seen, the cycle of day and night will still continue. Therefore, the crowing of roosters is an instinctive reaction to the dawn, not a reason. This is an interesting biological phenomenon that shows the ability of animals to adapt to environmental changes.