Tian Tian holds a large stalk of bamboo while Mei Xiang, the female giant panda, stands just behind him.
Pandas have a thumb-like appendage which has evolved from a wrist bone on each forepaw.
It and the first digit come together, allowing giant pandas to grasp and hold bamboo. The pandas go on public display. Crowds gather at the National Zoo to get their first look at Tian Tian and Mei Xiang. Live video from the Zoo, camera one. Live video from the Zoo, camera two.