Knut, the polar bear cub, makes its first public appearance at the Berlin Zoo, in this Friday, March 23, 2007 file photo. Celebrity polar bear Knut, who won the hearts of millions around the globe as a roly-poly orphan cub, celebrated his first birthday Wednesday, Dec. 5, 2007, with a cake made from 300 eggs and 20 pounds of marzipan. [Agencies]