Why do dragons have two kinds of calls?

As a totem of the Chinese nation, dragon represents Yang in the world view of Yin and Yang. In feudal times, the dragon was the symbol of the emperor, and the image of the dragon appeared on various things used by the emperor, such as the Dragon Pavilion, the Dragon Palace and the Dragon Robe. In the late new period, the embryonic form of the dragon began to sprout, which was a virtual imagination with the theme of Xia totem. In the long historical process of China, the image of dragon began a long and complicated development and evolution from Shang Dynasty.

As a traditional pattern of ceramic decoration in China, there are simple dragon patterns, as well as composite patterns combined with other patterns, such as Yunlong pattern and seawater dragon pattern. As early as the new era, people used dragon decoration in ceramic production. The dragon pattern at this time may be the symbol of clan and tribe, which is closely related to clan totem. In the Shang and Zhou Dynasties, dragon patterns still frequently appeared on various ceramic objects. During the Yuan Dynasty, the dragon pattern production technology developed to a higher level. During the Ming and Qing Dynasties, dragon pattern production reached its peak. It is worth mentioning that in the image of dragons in the Ming and Qing Dynasties, two whiskers appeared on the upper jaw of dragons, and at the same time, the image of dragons became more colorful, such as pterodactyl, frontal dragon, standing dragon, Lianchi dragon and Huajian dragon.

Dragon images on ceramics in Shang and Zhou dynasties can be roughly divided into two types: one is snake-shaped and claw-free scale-shaped dragon, and generally this dragon pattern is two-body or two-body; The other is the animal-shaped dragon pattern, with wide eyes, limbs and claws, a body like an animal's body and a curly tail. The dragon patterns that appeared in the Spring and Autumn Period and the Warring States Period are all animal-shaped, with three-toed claws, a thin and curly tail, an open faucet and a dragon horn rolled back.