Descendants of the Dragon
A totem is any supposed entity that watches over or assists a group of people, such as a family, clan, or tribe.
Many Chinese people often use the term "Descendants of the Dragon" as a sign of ethnic identity, or totem. But this has not always been the case.
The Yellow River is called "the cradle of Chinese civilization", as its basin is the birthplace of the northern Chinese civilizations, Chinese history begins with the Three August Ones (San Huang, or sometimes called three Sovereigns), followed by the Five Emperors (Wu Di).
The three August Ones were said to be god-kings or demigods.
Shennong the 'Blazing Sovereign' reigned 120 years, his tribe used dragon or ox as totems. His mother was influenced by a sacred dragon, she brought forth the blazing god with a man's body and an ox's head. This was Shennong, he has an ox body, but his mother was influenced by a dragon, which might be another tribe's totem used by the tribe of Shennong's father.
Fuxi's mother, named Huaxu, trod in the footprint of giant at Thunder lake, and bore him at Chengji. Fuxi had a serpent's body, a man's head, and the virtue of sage. Obviously, the tribe of Fuxi used snake or serpent as it's totem. Fuxi reigned for eleven years and died.
Nuwa came to the throne in the room of Fuxi. He also had the body of serpent, the head of a man, and the virtue of a holy man. Nuwa was believed to be creating mankind and repairing the wall of heaven. Because his name, Nuwa has been sometimes regarded as a goddess, appeared in paintings as a female with serpent body.
And by the Han Dynasty, she is described in literature with her husband Fuxi as the first of the Three August Ones, and often called the "parents of humankind". One of the paintings depicted them joined as half people - half snake. This implies a marriage between these two tribes.
The totem of Yin was Black Bird. The Yin Dynasty started from Emperor Qie, whose mother Jiandi was one of the daughters of Yusong and the secondary wife of Emperor Ku. She was going with her two sisters to bathe, when she saw a dark bird drop its egg. Jiandi picked it up, and swallowed it, and thus being with child gave birth to Qie.