Giant pandas gestate for 1.5 months after fertilization, and they are born blind and helpless at a weight of between 0.2 and 0.3 pounds. Unlike most bears, they are born with a thin layer of fur. They first open their eyes at about three weeks old.
Giant pandas mate between March and May, but the females usually delay implantation and development of the fertilized egg between 1.5 and four months, until conditions are right. Most of the cubs are born between August and September. Between one and three cubs are born at a time, and a cub suckles for about 46 weeks before weaning. In the case of multiple births, the mother generally selects one cub, and the others are allowed to die. The cubs stay with their mothers for up to 18 months.
Pandas usually live around 26 years in captivity, but their lifespan in the wild is not known. Giant pandas grow to weigh between 176 and 275 pounds as adults. Their adult length is between about 5 and 6 feet. They are stocky in shape, with enlarged shoulders and a short back, which gives them an ambling gait. Adult pandas have broader molars than other bears, with ridges to help them crush bamboo.