"They are vivid creations. Their layers of feathers and feet as thin as paper can clearly be seen. They look as if they are alive," says Wang.

One of the bronze cranes is holding a worm in its beak, frozen at the moment the crane plucked it from the water. A wild goose raises its long neck, sending its cries toward the sky. The figures kneel in front of the birds in poses that suggest they are playing music.

The techniques used are sophisticated. The craftsmen applied pigments made from mineral stones onto parts of the birds. Patterns on each part, such as the neck and belly, were also painted differently.

Experts say that, based on relics discovered in the pit, there was once a music department and a garden housing waterfowl for the amusement of the imperial family at the emperor's complex.