Scientists don't know very much about the lives of these animals. They don't roar like other bears, but they do have 11 different calls, four of which are only used during mating. The giant panda's life span in the wild has not been accurately documented, but Chinese scientists report that some pandas in zoos have lived to be 35 years old. Hsing-Hsing, who lives in the National Zoo, turned 29 in 1999. Most animals live longer in captivity than in the wild.
Pandas are good tree climbers, using their short claws to grab onto the bark.
Sometimes they take afternoon naps high in the trees. Unlike many other bears, pandas cannot walk on their hind legs. Also, the bamboo they eat is not high enough in nourishment to fatten them up for the winter. They don't seem to have permanent dens. Male and female giant pandas mate in the spring, attracting each other with calls and odors.