The twelve Chinese zodiac signs are the twelve animals Chinese people customarily use to mark the year in which a person was born. The twelve animals and the order in which they are arranged are called “the twelve zodiac signs”. The twelve animals are rat, ox, tiger, rabbit, dragon, snake, horse, goat, monkey, rooster, dog, and pig.
The formation of the twelve animal signs is based on astronomy and has something to do with the Chinese way of numbering the years according to Heavenly Stems and Earthly Branches. Marking a person’s year of birth by combining numbers from the ten Heavenly Stems and the twelve Earthly Branches is no easy thing for most people.
In order to make things easier for calculation and remembering, a system of twelve animals like rat and ox, representing numbers in the Heavenly Stems and Earthly Branches was adopted, with one animal marking the zodiac sign of each year. This special way of marking a person’s age is a unique phenomenon in Chinese folk culture.
As to why these particular twelve animals are chosen, there are lots of legends in Chinese folk culture. The relatively scientific account is that the decision was from the primitive worship of animals. Another opinion is that the selection and sequence of the twelve animals was determined by the activity time of each animal. For example, the rat has been chosen to represent midnight, because it becomes active at night.
The twelve animal signs are not unique to the Han people. Many ethnic minorities also use them to number years, but there may be some difference in the animals selected.
The Selection & Arrangement of the 12 Zodiac Animals
The selection and arrangement of the 12 zodiac animals are said to be based on the active time of each animal during a day. The period from11:00 pm to 01:00am is the Chinese hour of Zi, during which the mouse gets most active. During the Chinese hour of Chou, i.e. the period of 01:00am and 03:00am, the ox is chewing the cud. In the Yin hour, which is from 03:00am to 05:00am, the tiger is loitering and seeking food. This is the time of day the tiger becomes most ferocious. The time period between 05:00am and 07:00am is called the hour of Fan. During this time, the sun is not out yet and the moon is in the sky. The Jade Rabbit in the moon is said to be busy pounding medicine in a mortar.
When the hour of Chen, 7:00am to 9:00am, arrives, it’s time for the divine dragon to control the rain. The period between 9:00am and 11:00am is called the Si hour, during which the snake becomes active. The Wu hour, which is between 11:00am and 01:00pm, the world abounds in the energy of yang. It’s time for the heavenly horse to soar across the sky. The period from 01:00pm to 03:00pm is the Wei hour, during which the sheep is eating grass and it’ll grow stronger. The Shen hour is from 03:00pm to 05:00pm. The monkey gets active during this period. When the You hour, i.e. 05:00pm to 07:00pm, comes, the rooster begins to return to its cage. The period from 07:00pm to 09:00pm is the Xu hour, during which the dog keeps watch. And the period between 9:00pm and 11:00pm is the Hai hour. During this period, everything is quiet and the pig is fast asleep.