Newborn: A newborn panda cub is only one-thousandth of the weight of its mother. The average weight is only about 120 grams, the lightest is 51 grams, and the heaviest is 225 grams. The cub has pink skin and white hair, its eyes and ears are not fully developed, nor its immune system.
One to two weeks old: its shoulder harness, limbs and ears become darker.
One month old: the cub starts growing black and white hair, it weighs 1-2 kg, and it can’t walk yet.
Six to eight weeks old: the cub can blink and starts to grow milk teeth.
Three months old: the cub can crawl slowly.
Six months old: the cub can walk freely and starts eating bamboo.
One year old: the cub has full milk teeth by now.
One and a half to two years old: the panda leaves its mother and starts living independently.
Sub-adult: this is the period when the panda is one year and a half, before becoming sexually mature. It’s like human beings’ teenage period. At this stage, the food of pandas has gradually shifted from nutrient-rich milk to bamboo with high fiber and low nutrition.
The panda becomes more mature physiologically and psychologically and starts breeding. Pandas are the most active during the age of 1-3. Every day, in addition to eating, they spend most of their time playing, exploring and climbing trees. When they’re 3 to 4 years old, they start growing permanent teeth.
Adult: the panda is about 160-180 cm long and weighs about 80-150 kg.
Pandas’ newborn cubs are very small, they’re similar in size to little pandas’ cubs, weighing only 90-131 grams (the heaviest one is only 170 grams), averaging about 100 grams, and they’re only 1/900 of the mother’s body weight. A black bear’s newborn cub is 1/200-1/300 of its mother’s size, which is more than 3 times larger than that of a panda’s.
Therefore, panda cubs are actually premature babies. When a panda baby is born, its eyes are closed, and its whole body is in a light red, flesh-like color. It also only has sparse white hair. The hair on its body is longer, about 0.5 cm. The hair on the head, limbs and tail is shorter, about 0.2 cm. Its tail is relatively longer, about 1/3 of its body length.
Its head shape is flatter and more blunt than its parents. Although the newborn cubs are small, they are quite loud, which can seem quite unusual comparing to how little they are. Sometimes, the crying sound of a newborn cub is like that of a newborn puppy. As they grow up, their crying sound becomes softer. Two months after they’re born, their crying sound similar to that of a baby, or a puppy, would disappear. It would be more like a form of calling.
When the cub is one week old, there starts to be sparse black hair growing on the ears, eyes and shoulders. When it’s ten days old, black hair is also found on the hind limbs, and that on the ears also become more obvious. The black hair around the eye circles become more rounded, and the diameter is about 1 cm long. When the cub is around two weeks ago, there is also black hair around the nostrils and corners of the mouth.
When it’s almost 20 days old, the black hair thickens, and it starts appearing on the chest, while that around the eye circles continues to expand, changing from a circle to a diagonal rectangle, similar to that of an adult panda. At this time, there is black hair on their necks, and on the front and back of their feet too. When they’re 25 days old, black hair spreads throughout the neck and chest, and the eye circles are enlarged more widely.
When the new white hair grows out, the black and white hair become more distinct. By the 50th day, the hair on the midline of the chest, and the lower part of the abdomen become reddish brown, the rest remains in black, but contain a slightly dark brown color. On the tip of the tail, there is a chunk of black hair too.
The limbs of a newborn panda are very weak and it can’t stand at all. Within two months after birth, it is basically inactive. All it does is to sleep and feed on milk. When the cub is hungry and when it looks for milk, it can at most make a tiny distance forward by crawling with all its strength. It often rolls between two sides.
After two months, the cub can start moving and crawling a little, but its limbs are still not well coordinated. When it’s two and a half months old, the cub’s hind limbs can start supporting the body, and it can make a few steps forward. At 3 months, its hind limbs begin to have more strength, and it can walk more than 1 meter, though its motion is still not stable enough and sometimes it falls over.
After 4 months, it can start running a little, and it rolls a lot. It often climbs on its mother’s back, rolls down and climbs back on. At 4 and a half months, it becomes so fond of activities. When its mother is eating bamboos, the cub imitates the action without actually eating it.
After six months old, the cub starts eating some bamboo leaves. The cub’s weight increase is initially slow, and it starts to grow more quickly in Spring. Generally, a male cub’s weight increases more than that of a female cub.