1. In 1972, the Chinese government gave two giant pandas, Hsing-Hsing and Ling-Ling, to the United States as a gesture of friendship. Hsing-Hsing, the male, and Ling-Ling, the female, lived at the Smithsonian's National Zoo in Washington, D.C.

2. The National Zoo's current panda pair, Tian Tian and Mei Xiang, debuted in 2001 and produced their first cub, Tai Shan, in 2005.

3. Giant pandas are one of the most endangered species in the world. Only about 1,600 pandas are estimated to live in the wild.

4. As bears, giant pandas have the digestive system of carnivores but have evolved to eat bamboo almost exclusively. Bamboo is not very nutritious, so giant pandas have to eat a lot, spending up to 16 hours per day consuming 33 to 66 pounds of food.

5. Giant pandas sit in an upright position while eating. They have an enlarged wrist bone on their front paws, which they use as an opposable thumb to grasp their food. They also have large molar teeth and strong jaw muscles for crushing tough bamboo.

6. Giant pandas are good tree climbers, using their short claws to grab onto the bark. Sometimes they even sleep in the trees.

7. Giant pandas are most active at twilight and night. Their pupils have vertical slits, like snakes and cats, which allow them to see better at night.

8. Giant pandas leave their scent on tree trunks and stones as a form of communication. Each panda's scent is unique and pandas use the scent to identify one another.

9. While they may seem quiet, giant pandas can bleat like a sheep, bark like a dog, and honk like a goose. They have up to 11 distinct calls.

10. Giant pandas' scientific name means "black and white cat-footed animal." Newborn pandas are pink and hairless and develop their distinctive black markings after about a month.