Ling-ling and Hsing-hsing

In 1972, President Nixon received a gift of two giant pandas from the Chinese government.

For many years scientists and Zoologists tried to help the pair produce offspring. But after 5 births no cub survived.

• ,Ling-ling, the female, died suddenly in1992 at age 23. At the time she was the oldest Giant Panda in captivity.

•  Hsing-hsing, the male, remained on display until his death in November 1999. He suffered from many ailments those last few years so he was put down to relieve him from further pain.

All photos above from the National zoo web site