Cocks cluck and crow.

Roosters crow about once an hour during the day, except that first crow in the morning cuts through the quiet of dawn, and the neighboring roosters take over to make an impression. Typically, chickens sleep at night. Chickens have a "pineal gland" in their brains. The pineal gland secretes a substance called melatonin. If there is light in the eyes, the secretion of melatonin is suppressed. Melatonin inhibits the production of sex hormones and directly controls bird song. When the morning light appears, melatonin secretion is suppressed, and the male chickens can't help but "morning"; throughout the year, when the days get longer, the melatonin level in the birds' bodies decreases, and they begin to "call spring".

Expanded:

Chickens are social animals, especially roosters, who are the parents, always have a ton of family chores to deal with and a lot of command and decision-making tasks to take on. For example, when the rooster finds food, he makes a squawking call to his concubines to come and share it. If the discovery is a delicacy like earthworms or beans, he will squawk more frequently. Conversely, when it finds a less attractive grain of rice, it calls less frequently.

Some hens also crow, or if they are injected with androgens, they will start to crow as well. This is due to the fact that only the left ovarian oviduct develops in the hen's body and the right one remains undifferentiated. If her left ovary malfunctions, the undifferentiated ovary on the right develops into a testicle and produces androgen. Prompted by the androgen, the hen can then crow just like a rooster.

References: