Another symbol in Chinese folk art was a pair of animals on each side of the tree of life. This was a common design in silk weaving pictures from the Silk Road. In the culture of primitive society, a tree meant the tree of life, and it was guarded by the two animals, one on each side. However, when such totem was introduced to China, the two animals from the opposite side were given a philosophical nature as yin and yang, male and female. The totem symbols in Chinese primitive society were the paired fish, toads, snakes, tigers, deer and birds, all paired up as male and female, yin and yang, or animals of earth and the sky.