Vessels made in animal form constitute virtually the only bronze sculpture known from the Shang period. Besides this well-known version of an owl, rare examples of quadrupeds including buffalo, boar, rhinoceros, elephant and ram have also survived. The "Pillsbury Owl" is the oldest and most naturalistic of the few remaining owl-shaped zun. Standing near the beginning of the Anyang period (1400-1027 BCE), it represents a charming, though seldom practiced and short-lived tradition of casting ceremonial vessels in the shapes of animals.