At the Denver Zoo, a bluffing big shot relies on the protection of Plexiglas to stare down an increasingly unhappy lion.

Today, Frosty the polar bear died at the Denver zoo. He was 25. At DC's National Zoo, a red panda (which is more like a raccoon) was born. As Elton John once said: The Cirrrrrclleeeeeee. The Cirrrrcccleeee of Lifffffeeeeeeee.