Says the article:
The knighthood ceremony began Friday morning with speeches and a fanfare before Nils arrived, under escort with the King's Guard Color Detachment. Nils then reviewed the troops lined up outside the penguin enclosure at the zoo, waddling down the row of uniformed soldiers, occasionally stopping to crane his neck and peer inquisitively at their crisp uniforms before being guided forward by his handler.
Nils was then knighted by British Maj. Gen. Euan Loudon on behalf of Norway's King Harald V. Loudon dropped the king's sword on both sides of Nils' black-and-white frame, and the penguin's colonel-in-chief badge, tied to his flipper, was swapped for one symbolizing his knighthood.
"He'll be a "sir" now," Finlay said.
It's the "he'll be a 'sir' now" that makes it art.