For example, where are the "biological clocks" of animals and plants in nature?

For example, where are the "biological clocks" of animals and plants in nature?

Pigs, cows and sheep: They move during the day. They start to sleep at night.

Cat: Sleep during the day. It becomes active at night.

Zombie: Stay in a tree hole during the day and come out after sunset.

Birds also get up on time.

At dawn in the east, the cock jumped up and first "sang loudly".

Then, the ducks woke up and scrambled to make a "quack" sound;

Before long, the early sparrows began to chirp and make noise;

Pulsatilla likes to sleep late. The golden sun has already shone on the earth, and they slowly let go of their voices.

Piano crabs hide in the dark during the day, when their body color will become darker; At night, they move around and their body color will become lighter.

Cockroaches are particularly active every night. Scientists put cockroaches in dark cages and found that their activity cycle is 23 hours and 53 minutes, which is very close to the rotation cycle of the earth!